US4905302A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trunked radio repeater system
Assignee: MA Com Private Radio Systems Canada Corp
•
Filing: 1987-06-03
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Granted: 1990-02-27
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Expires: 2007-06-03
Abstract
Abstract A digitally trunked radio repeater system provides substantial improvements in timeliness of channel acquisition and channel drop, and in reliability of critical control signalling. The system uses a much higher digital signalling rate than is typically found in prior art systems, and uses a control channel to convey digital channel request and assignment messages between the central site and mobile transceivers. The mobile radio transceivers transmit channel requests on the control channel (if no response is received, the mobile retries during a retry time window which increases in duration in dependence on the number of retries). The mobile transceiver switches to a working channel in response to an assignment message received on the control channel. Subaudible digital signals transmitted on the control channel and on active working channels allow late entry, shifting to higher priority calls, and other advanced functions. Message and transmission trunking capabilities are both present so as to maximize working channel usage without compromising channel access for high priority communications. During transmission trunking, called and calling transceivers return to the control channel after each transmission (and called transceivers may be inhibited from transmitting) but grant higher priority to calls from the other transceivers being communicated with to ensure continuity over an entire conversation. Additional functions and fault tolerant features further increase the versatility and reliability of the system.
Inventors
- 👤 Jeffrey S. Childress
- 👤 Marc A. Dissosway
- 👤 Gerald M. Cooper
- 👤 Houston H. Hughes, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:33
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/24; H04W; H04W84/00; H04W84/02; H04W84/04; H04W84/08; H04L; H04L1/00; H04L1/12; H04L1/16; H04L1/1607; H04L1/1614
Claims Analysis
Total Claims: 101
Claim 1
Independent Claim
175 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals transmitted over the control channel, said control channal carrying inbound digital control signals from said radio units to a control site, said inbound digital control signals having a time-multiplexed format defining discrete signalling slots, said method comprising the steps of: (a) requesting assignment of a working channel by passing digital request signals from a first radio unit to said control site over a control channel inbound digital signalling slot; (b) monitoring said control channel for responsive channel assignment signals returned over the control channel from the control site within a predetermined expected response time; and (c) if no such responsive channel assignment signals are detected, then (c1) repeating steps (a) and (b) within a retry time window, and (c2) increasing the duration of the retry time window as a function of the number of retries.
Claim 2
Independent Claim
175 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals transmitted over the control channel, said control channal carrying inbound digital control signals from said radio units to a control site, said inbound digital control signals having a time-multiplexed format defining discrete signalling slots, said method comprising the steps of: (a) requesting assignment of a working channel by passing digital request signals from a first radio unit to said control site over a control channel inbound digital signalling slot; (b) monitoring said control channel for responsive channel assignment signals returned over the control channel from the control site within a predetermined expected response time; and (c) if no such responsive channel assignment signals are detected, then (c1) repeating steps (a) and (b) within a retry time window, and (c2) increasing the duration of the retry time window as a function of the number of retries.
Claim 3
Dependent Claim
20 words
A method as in claim 1 wherein said repeating occurs at a randomly variable time within said retry time window.
Claim 4
Dependent Claim
50 words
A method as in claim 1 wherein said digital request signals are transmitted as messages within predetermined time slots and said increasing step (c2) increases the duration of said retry time window in accordance with the following tabulation: first retry=two slot variability second retry=four slot variability succeeding retries=eight slot variability.
Claim 5
Dependent Claim
51 words
A method as in claim 1 wherein: said signalling slots of said digital control signals transmitted over the control channel have a certain duration; and said increasing step (c2) increases the duration of the retry time window also as a function of said certain duration of said control channel signalling slots.
Claim 6
Dependent Claim
33 words
A method as in claim 1 wherein said increasing step (c2) increases said retry time window duration by a time interval related to the duration of said control channel inbound digital signalling slots.
Claim 7
Dependent Claim
170 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals transmitted over the control channel, said control channel carrying inbound digital control signals from said radio units to a control site, said inbound digital control signals having a time-multiplexed format defining discrete signalling slots, said apparatus comprising: (a) means for requesting assignment of a working channel by passing digital request signals over a control channel inbound signalling slot; (b) means for monitoring said control channel for responsive channel assignment signals returned over the control channel within a predetermined expected response time; (c) means for repeating said request and monitoring functions within a retry time window if there is no detection of such responsive channel assignment signals; and (d) means connected to said repeating means for increasing the duration of said retry time window as a function of the number of retries.
Claim 8
Dependent Claim
170 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals transmitted over the control channel, said control channel carrying inbound digital control signals from said radio units to a control site, said inbound digital control signals having a time-multiplexed format defining discrete signalling slots, said apparatus comprising: (a) means for requesting assignment of a working channel by passing digital request signals over a control channel inbound signalling slot; (b) means for monitoring said control channel for responsive channel assignment signals returned over the control channel within a predetermined expected response time; (c) means for repeating said request and monitoring functions within a retry time window if there is no detection of such responsive channel assignment signals; and (d) means connected to said repeating means for increasing the duration of said retry time window as a function of the number of retries.
Claim 9
Dependent Claim
26 words
Apparatus as in claim 6 wherein said means for repeating causes said repeated requests to occur at a randomly variable time within said retry time window.
Claim 10
Dependent Claim
49 words
Apparatus as in claim 6 wherein said digital request signals are transmitted as messages within predetermined time slots and said duration increasing means causes said time window to be progressively increased in accordance with the following tabulation: first retry=two slot variability second retry=four slot variability succeeding retries=eight slot variability.
Claim 11
Dependent Claim
48 words
Apparatus as in claim 6 wherein: said signalling slots of said digital control signals transmitted over the control channel have a certain duration; and said increasing means includes means for including the retry time window as a function of said certain duration of said control channel signalling slots.
Claim 12
Dependent Claim
34 words
Apparatus as in claim 6 wherein said increasing means includes means for increasing said retry time window duration by a time interval related to the duration of said control channel inbound digital signalling slots.
Claim 13
Independent Claim
100 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: monitoring a predetermined digital data field received via subaudible signals transmitted repeatedly over an assigned working channel after operation of a radio unit has been established thereon, and dropping operation of a radio unit from said working channel in response to a detected change in said predetermined digital data field.
Claim 14
Independent Claim
100 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: monitoring a predetermined digital data field received via subaudible signals transmitted repeatedly over an assigned working channel after operation of a radio unit has been established thereon, and dropping operation of a radio unit from said working channel in response to a detected change in said predetermined digital data field.
Claim 15
Dependent Claim
33 words
A method as in claim 11 further comprising the step of: changing the said predetermined data field transmitted on a given working channel each time a new assignment of that channel is made.
Claim 16
Dependent Claim
26 words
A method as in claim 12 wherein said predetermined data field comprises a multi-bit binary counter field which is changed by incrementing its contained count value.
Claim 17
Dependent Claim
99 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for monitoring a predetermined digital data field received via subaudible signals transmitted over an assigned working channel after operation of a radio unit has been established thereon; and means for dropping operation of a radio unit from said working channel in response to a detected change in said predetermined digital data field.
Claim 18
Dependent Claim
99 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for monitoring a predetermined digital data field received via subaudible signals transmitted over an assigned working channel after operation of a radio unit has been established thereon; and means for dropping operation of a radio unit from said working channel in response to a detected change in said predetermined digital data field.
Claim 19
Dependent Claim
31 words
Apparatus as in claim 14 further comprising: means for changing the said predetermined data field transmitted on a given working channel each time a new assignment of that channel is made.
Claim 20
Dependent Claim
28 words
Apparatus as in claim 15 including means for defining said predetermined data field as a multi-bit binary counter field which is changed by incrementing its contained count value.
Claim 21
Independent Claim
135 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said method comprising the steps of: detecting, by testing control signals provided on at least one of said control channel or assigned working channel at each radio unit involved in a communique, a trunked status signal identifying whether the then assigned usage of the working channel is to be transmission or message trunked; immediately reverting operation of a calling unit to the control channel upon PTT release if transmission-trunked status has been detected; and preventing transmissions from a called unit on the assigned working channel if transmission-trunked status has been detected.
Claim 22
Independent Claim
135 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said method comprising the steps of: detecting, by testing control signals provided on at least one of said control channel or assigned working channel at each radio unit involved in a communique, a trunked status signal identifying whether the then assigned usage of the working channel is to be transmission or message trunked; immediately reverting operation of a calling unit to the control channel upon PTT release if transmission-trunked status has been detected; and preventing transmissions from a called unit on the assigned working channel if transmission-trunked status has been detected.
Claim 23
Dependent Claim
148 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for testing a trunked status signal within control signals provided on at least one of said control channel or assigned working channel at each radio unit involved in a communique; means connected to said testing means for determining in response to said testing whether the then assigned usage of the working channel is to be transmission or message trunked; means for immediately reverting operation of a calling unit to the control channel upon PTT release if transmission-trunked status has been detected; and means for preventing transmissions from a called unit on the assigned working channel if transmission-trunked status has been detected.
Claim 24
Dependent Claim
148 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for testing a trunked status signal within control signals provided on at least one of said control channel or assigned working channel at each radio unit involved in a communique; means connected to said testing means for determining in response to said testing whether the then assigned usage of the working channel is to be transmission or message trunked; means for immediately reverting operation of a calling unit to the control channel upon PTT release if transmission-trunked status has been detected; and means for preventing transmissions from a called unit on the assigned working channel if transmission-trunked status has been detected.
Claim 25
Independent Claim
135 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: monitoring said control channel for a working channel assignment for a communique initiated by a calling radio unit; recording the identity of the calling radio unit within a called radio unit; subsequently automatically initiating a channel assignment call request from the just-called radio unit back to the earlier said calling radio unit using said recorded identity of the earlier said calling radio unit if a PTT switch of the just-called radio is actuated within a predetermined time period after cessation of the just earlier communique.
Claim 26
Independent Claim
135 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: monitoring said control channel for a working channel assignment for a communique initiated by a calling radio unit; recording the identity of the calling radio unit within a called radio unit; subsequently automatically initiating a channel assignment call request from the just-called radio unit back to the earlier said calling radio unit using said recorded identity of the earlier said calling radio unit if a PTT switch of the just-called radio is actuated within a predetermined time period after cessation of the just earlier communique.
Claim 27
Dependent Claim
138 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for monitoring said control channel for a working channel assignment for a communique initiated by a calling radio unit; means for recording the identity of the calling radio unit within a called radio unit; and means for subsequently automatically initiating a channel assignment call request from the just-called radio unit back to the earlier said calling radio unit using said recorded identity of the earlier said calling radio unit if a PTT switch of the just-called radio is actuated within a predetermined time period after cessation of the just earlier communique.
Claim 28
Dependent Claim
138 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for monitoring said control channel for a working channel assignment for a communique initiated by a calling radio unit; means for recording the identity of the calling radio unit within a called radio unit; and means for subsequently automatically initiating a channel assignment call request from the just-called radio unit back to the earlier said calling radio unit using said recorded identity of the earlier said calling radio unit if a PTT switch of the just-called radio is actuated within a predetermined time period after cessation of the just earlier communique.
Claim 29
Independent Claim
122 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said method comprising the steps of: monitoring the control channel for working channel assignments addressed to a predetermined radio unit; shifting said radio unit's operation to an assigned working channel in response to detection of such assignment on the control channel; and initially, upon arrival on the assigned working channel, simultaneously monitoring that working channel for an extended dotting signal and for confirmation signals confirming the assignment of that particular channel to said radio unit for a communique.
Claim 30
Independent Claim
122 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said method comprising the steps of: monitoring the control channel for working channel assignments addressed to a predetermined radio unit; shifting said radio unit's operation to an assigned working channel in response to detection of such assignment on the control channel; and initially, upon arrival on the assigned working channel, simultaneously monitoring that working channel for an extended dotting signal and for confirmation signals confirming the assignment of that particular channel to said radio unit for a communique.
Claim 31
Dependent Claim
98 words
A method as in claim 21 wherein said initial monitoring of said assigned working channel includes: shifting radio operations back to the control channel if said extended duration dotting signal is detected: if said confirmation signals confirm the assignment of that particular channel to said radio unit, locking radio operations onto the assigned working channel and muting an output signal; subsequently unmuting said output signal upon detection of further predetermined unmuting signals on the assigned working channel; and upon cessation of said confirmation signals, if any, monitoring the assigned working channel for subaudible signalling and for unmuting signals.
Claim 32
Dependent Claim
36 words
A method as in claim 21 further comprising: upon receipt of drop channel signalling, dropping said working channel and ignoring any channel updates to the address and working channel just dropped for a predetermined time period.
Claim 33
Dependent Claim
106 words
A method as in claim 21 in which, upon release of a PTT switch at a calling radio, an unkeyed message is transmitted to a central control site over the then assigned working channel and, in turn, wherein the central control site responds to the unkeyed message by: transmitting dotting signals for a first predetermined time period to constitute a drop channel signal to all radio units then residing on the assigned working channel; and interrupting said drop channel signal and immediately sending an addressed channel assignment confirmation message over the already assigned working channel if requests for further communiques are queued at the control site.
Claim 34
Dependent Claim
123 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for monitoring the control channel for working channel assignments addressed to a predetermined radio unit; means for shifting said radio unit's operation to an assigned working channel in response to detection of such assignment on the control channel; and means for simultaneously monitoring the assigned working channel initially upon arrival thereat for a dotting signal of extended duration and for confirmation signals confirming the assignment of that particular channel to said radio unit for a communique.
Claim 35
Dependent Claim
123 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said apparatus comprising: means for monitoring the control channel for working channel assignments addressed to a predetermined radio unit; means for shifting said radio unit's operation to an assigned working channel in response to detection of such assignment on the control channel; and means for simultaneously monitoring the assigned working channel initially upon arrival thereat for a dotting signal of extended duration and for confirmation signals confirming the assignment of that particular channel to said radio unit for a communique.
Claim 36
Dependent Claim
111 words
Apparatus as in claim 25 wherein said means for simultaneously monitoring of said assigned working channel includes: means for shifting radio operations back to the control channel if said extended duration dotting signal is detected; means for detecting said confirmation signals; means connected to said detecting means for locking radio operations onto the assigned working channel if said detecting means detects said confirmation signals; means for providing a muted radio output and for subsequently unmuting said output in response to detection of unmuting signals on the assigned working channel; and means for monitoring the assigned working channel for subaudible and for unmuting signals upon cessation of said confirmation signals, if any.
Claim 37
Dependent Claim
47 words
Apparatus as in claim 25 further comprising: means for dropping said working channel in response to receipt of channel drop signalling; and means for ignoring any channel updates to the address and working channel just dropped for a predetermined time period after receipt of drop channel signalling.
Claim 38
Dependent Claim
112 words
Apparatus as in claim 25 in which, upon release of a PTT switch at a calling radio, an unkeyed message is transmitted to a central control site over the then assigned working channel and, in turn, wherein the central control site includes means for responding to the unkeyed message comprising: means for transmitting dotting signals for a first predetermined time period to constitute a drop channel signal to all radio units then residing on the assigned working channel; and means for interrupting said drop channel signal and immediately sending an addressed channel assignment confirmation message over the already assigned working channel if requests for further communiques are queued at the control site.
Claim 39
Independent Claim
152 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals over said control channel; exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units; and releasing said units for communication over said assigned working channel by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 40
Independent Claim
152 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals over said control channel; exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units; and releasing said units for communication over said assigned working channel by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 41
Dependent Claim
17 words
A method as in claim 29 wherein said handshake signals are exchanged with said first radio unit.
Claim 42
Dependent Claim
16 words
A method as in claim 29 wherein said release signals are sent from said control site.
Claim 43
Dependent Claim
20 words
A method as in claim 29 wherein all said digital signals are communicated reliably at substantially 9600 bits per second.
Claim 44
Dependent Claim
36 words
A method as in claim 29 wherein said control signals, request signals and handshake signals include triple data redundancy and said assignment signals include six-fold redundancy of data representing the called party and the assigned channel.
Claim 45
Dependent Claim
87 words
A method as in claim 29 wherein a certain priority is associated with said working channel assignment and said method further comprises the steps of: transmitting digital, subaudible new channel assignment updated messages on the assigned working channel, said new channel assignment updated messages having priorities associated therewith; and monitoring said update messages in each radio unit and responsively dropping off the assigned working channel if the priority associated with a new channel updated message directed to said each radio unit is higher than the certain priority.
Claim 46
Dependent Claim
57 words
A method as in claim 34 wherein: said assigning step includes the step of incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting step includes transmitting said incremented count value within each of said subaudible updated messages, and continually transmitting said subaudible updated messages over said working channel.
Claim 47
Dependent Claim
50 words
A method as in claim 34 wherein: said assigning step includes the step of incrementing a two-bit subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting step includes the step of transmitting said incremented count value within each of said subaudible updated messages.
Claim 48
Dependent Claim
45 words
A method as in claim 29 further comprising the step of: subsequently transmitting digital channel assignment late entry messages on the control channel to permit the late entry of a called unit specified by said initial digital assignment signals to an ongoing working channel communication.
Claim 49
Dependent Claim
63 words
A method as in claim 29 further comprising the steps of: sending, from the calling unit on the assigned working channel, a digital unkeyed message, and responsive to said unkeyed message, sending, from said control site on said assigned working channel, a digital drop signal which causes all units to drop off the then-assigned working channel thus freeing it for immediate further assignment.
Claim 50
Independent Claim
194 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals from said control site to said radio units over said control channel; confirming said assignment by sending digital confirmation signals on said assigned working channel from said control site; achknowledging successful receipt of said assignment and confirmation signals by at least one of said units, including sending digital acknowledgement signals from said at least one unit to said control site over said assigned working channel in response to said confirmation signals; and releasing at least one of said units for communication by sending digital release signals over said assigned working channel in response to said acknowledgement signals.
Claim 51
Independent Claim
194 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals from said control site to said radio units over said control channel; confirming said assignment by sending digital confirmation signals on said assigned working channel from said control site; achknowledging successful receipt of said assignment and confirmation signals by at least one of said units, including sending digital acknowledgement signals from said at least one unit to said control site over said assigned working channel in response to said confirmation signals; and releasing at least one of said units for communication by sending digital release signals over said assigned working channel in response to said acknowledgement signals.
Claim 52
Dependent Claim
16 words
A method as in claim 39 wherein said acknowledgement signals are sent from said first unit.
Claim 53
Dependent Claim
16 words
A method as in claim 39 wherein said release signals are sent from said control site.
Claim 54
Dependent Claim
20 words
A method as in claim 41 wherein said second unit is enabled to communicate by receipt of said release signals.
Claim 55
Dependent Claim
16 words
A method as in claim 42 wherein said acknowledgement signals are sent from said first unit.
Claim 56
Dependent Claim
16 words
A method as in claim 41 wherein said acknowledgement signals are sent from said first unit.
Claim 57
Dependent Claim
39 words
A method as in claim 39 wherein said request signals, assignment signals, acknowledgement signals and release signals are all digitally encoded and communicated reliably at substantially 9600 bits per second over said control channel and assigned working channel, respectively.
Claim 58
Dependent Claim
39 words
A method as in claim 39 wherein: said control signals, said request signals and said confirmation signals each include triple data redundancy, and said assignment signals include six-fold redundancy of data representing the called party and the assigned channel.
Claim 59
Dependent Claim
87 words
A method as in claim 39 wherein a certain priority is associated with said working channel assignment and said method further comprises the steps of: transmitting digital, subaudible new channel assignment updated messages on the assigned working channel, said new channel assignment updated messages having priorities associated therewith; and monitoring said update messages in each radio unit and responsively dropping off the assigned working channel if the priority associated with a new channel updated message directed to said each radio unit is higher than the certain priority.
Claim 60
Dependent Claim
57 words
A method as in claim 47 wherein: said assigning step includes the step of incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting step includes transmitting said incremented count value within each of said subaudible updated messages, and continually transmitting said subaudible updated messages over said working channel.
Claim 61
Dependent Claim
57 words
A method as in claim 47 wherein: said assigning step includes the step of incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting step includes transmitting said incremented count value within each of said subaudible updated messages, and continually transmitting said subaudible updated messages over said working channel.
Claim 62
Dependent Claim
45 words
A method as in claim 39 further comprising the step of: subsequently transmitting digital channel assignment late entry messages on the control channel to permit the late entry of a called unit specified by said initial digital assignment signals to an ongoing working channel communication.
Claim 63
Dependent Claim
63 words
A method as in claim 39 further comprising the steps of: sending, from the calling unit on the assigned working channel, a digital unkeyed message, and responsive to said unkeyed message, sending, from said control site on said assigned working channel, a digital drop signal which causes all units to drop off the then-assigned working channel thus freeing it for immediate further assignment.
Claim 64
Independent Claim
159 words
A system of apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising: means for requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; means for assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals over said control channel; means for exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units; and means for releasing said units for communication over said assigned working channel by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 65
Independent Claim
159 words
A system of apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising: means for requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; means for assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals over said control channel; means for exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units; and means for releasing said units for communication over said assigned working channel by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 66
Dependent Claim
107 words
A system as in claim 52 wherein said working channel assignment has a certain priority associated therewith and said system further comprises: means for transmitting digital, subaudible new channel assignment updated messages on the assigned working channel, said new channel assignment updated messages having priorities associated therewith; means for monitoring said update messages in each unit, means connected to said monitoring means for detecting the priorities of said monitored update messages, and means connected to said detecting means for responsively dropping off the assigned working channel if the priority associated with a new channel updated message directed to said monitoring means is higher than said certain priority.
Claim 67
Dependent Claim
60 words
A system as in claim 53 wherein: said assigning means includes means for incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting means includes means for transmitting said incremented count value within each of said subaudible updated messages, and means for continually transmitting said subaudible updated messages over said working channel.
Claim 68
Dependent Claim
47 words
A system as in claim 53 wherein: said assigning means includes means for incrementing a two-bit subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting means includes means for said incremented count value within each of said subaudible updated messages.
Claim 69
Dependent Claim
44 words
A system as in claim 52 further comprising: means for subsequently transmitting digital channel assignment late entry messages on the control channel to permit the late entry of a called unit specified by said initial digital assignment signals to an ongoing working channel communication.
Claim 70
Dependent Claim
64 words
A system as in claim 52 further comprising: means for sending, from the calling unit on the assigned working channel, a digital unkeyed message, and means responsive to said unkeyed message, for sending, from said control site on said assigned working channel, a digital drop signal which causes all units to drop off the then-assigned working channel thus freeing it for immediate further assignment.
Claim 71
Independent Claim
203 words
A system for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising: means for requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; means for assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals from said control site to said radio units over said control channel; means for confirming said assignment by sending digital confirmation signals on said assigned working channel from said control site; means for acknowledging successful receipt of said assignment and confirmation signals by at least one of said units, including means for sending digital acknowledgement signals from said at least one unit to said control site over said assigned working channel in response to said confirmation signals; and means for releasing at least one of said units for communication by sending digital release signals over said assigned working channel in response to said acknowledgement signals.
Claim 72
Independent Claim
203 words
A system for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising: means for requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel; means for assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals from said control site to said radio units over said control channel; means for confirming said assignment by sending digital confirmation signals on said assigned working channel from said control site; means for acknowledging successful receipt of said assignment and confirmation signals by at least one of said units, including means for sending digital acknowledgement signals from said at least one unit to said control site over said assigned working channel in response to said confirmation signals; and means for releasing at least one of said units for communication by sending digital release signals over said assigned working channel in response to said acknowledgement signals.
Claim 73
Dependent Claim
37 words
A system as in claim 58 wherein said request signals, assignment signals, acknowledgement signals and release signals are all digitally encoded and communicated reliably at substantially 9600 bps over said control channel and assigned working channel, respectively.
Claim 74
Dependent Claim
39 words
A system as in claim 58 wherein: said control signals, said request signals and said confirmation signals each include triple data redundancy, and said assignment signals include six-fold redundancy of data representing the called party and the assigned channel.
Claim 75
Independent Claim
119 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: requesting assignment of a working channel; monitoring for digital working channel assignment signals over said control channel issued in response to said requested assignment; exchanging digital handshake signals over said assigned working channel between said control site and said radio units; and releasing said assigned working channel for communication over by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 76
Independent Claim
119 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of: requesting assignment of a working channel; monitoring for digital working channel assignment signals over said control channel issued in response to said requested assignment; exchanging digital handshake signals over said assigned working channel between said control site and said radio units; and releasing said assigned working channel for communication over by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 77
Dependent Claim
16 words
A method as in claim 61 wherein said release signals are sent from said control site.
Claim 78
Dependent Claim
20 words
A method as in claim 61 wherein all said digital signals are communicated reliably at substantially 9600 bits per second.
Claim 79
Dependent Claim
36 words
A method as in claim 61 wherein said control signals, request signals and handshake signals include triple data redundancy and said assignment signals include six-fold redundancy of data representing the called party and the assigned channel.
Claim 80
Dependent Claim
86 words
A method as in claim 61 wherein said working channel assignment has a certain priority associated therewith and said system further comprises the steps of: transmitting digital, subaudible new channel and assignment updated messages on the assigned working channel, said new channel assignment updated messages having priorities associated therewith; monitoring said update messages in each radio unit; and responsively dropping off the assigned working channel if the priority associated with a new channel updated message directed to said monitoring means is higher than said certain priority.
Claim 81
Dependent Claim
57 words
A method as in claim 65 wherein: said assigning step includes the step of incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting step includes transmitting said incremented count value within each of said subaudible updated messages, and continually transmitting said subaudible updated messages over said working channel.
Claim 82
Dependent Claim
57 words
A method as in claim 65 wherein: said assigning step includes the step of incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting step includes transmitting said incremented count value within each of said subaudible updated messages, and continually transmitting said subaudible updated messages over said working channel.
Claim 83
Dependent Claim
45 words
A method as in claim 61 further comprising the step of: subsequently transmitting digital channel assignment late entry messages on the control channel to permit the late entry of a called unit specified by said initial digital assignment signals to an ongoing working channel communication.
Claim 84
Independent Claim
129 words
A system of apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising: means for requesting assignment of a working channel; means for assigning a specific working channel to radio unit by passing digital assignment signals over said control channel; means for exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units; and means for releasing said assigned working channel for communication thereover by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 85
Independent Claim
129 words
A system of apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising: means for requesting assignment of a working channel; means for assigning a specific working channel to radio unit by passing digital assignment signals over said control channel; means for exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units; and means for releasing said assigned working channel for communication thereover by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.
Claim 86
Dependent Claim
107 words
A system as in claim 69 wherein said working channel assignment has a certain priority associated therewith and said system further comprises: means for transmitting digital, subaudible new channel assignment updated messages on the assigned working channel, said new channel assignment updated messages having priorities associated therewith; means for monitoring said update messages in each unit; means connected to said monitoring means for detecting the priorities of said monitored update messages; and means connected to said detecting means for responsively dropping off the assigned working channel if the priority associated with a new channel updated message directed to said monitoring means is higher than said certain priority.
Claim 87
Dependent Claim
60 words
A system as in claim 70 wherein: said assigning means includes means for incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting means includes means for transmitting said incremented count value within each of said subaudible updated messages, and means for continually transmitting said subaudible updated messages over said working channel.
Claim 88
Dependent Claim
60 words
A system as in claim 70 wherein: said assigning means includes means for incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting means includes means for transmitting said incremented count value within each of said subaudible updated messages, and means for continually transmitting said subaudible updated messages over said working channel.
Claim 89
Dependent Claim
45 words
A method as in claim 69 further comprising the step of: subsequently transmitting digital channel assignment late entry messages on the control channel to permit the late entry of a called unit specified by said initial digital assignment signals to an ongoing working channel communication.
Claim 90
Dependent Claim
65 words
A system as in claim 69 further comprising: means for sending, from the calling unit on the assigned working channel, a digital unkeyed message, and means for responsive to said unkeyed message, for sending, from said control site on said assigned working channel, a digital drop signal which causes all units to drop off the then-assigned working channel thus freeing it for immediate further assignment.
Claim 91
Dependent Claim
132 words
A radio unit for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said radio unit comprising: means for requesting assignment of a working channel by passing digital request signals to a control site over said control channel; means for detecting digital working channel assignment signals over said control channel; means for exchanging digital handshake signals with said control site over said assigned working channel, and means for detecting digital release signals on said assigned working channel after successful exchange of said handshake signals and for unmuting communication over the assigned working channel in response to said detected release signals.
Claim 92
Dependent Claim
132 words
A radio unit for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said radio unit comprising: means for requesting assignment of a working channel by passing digital request signals to a control site over said control channel; means for detecting digital working channel assignment signals over said control channel; means for exchanging digital handshake signals with said control site over said assigned working channel, and means for detecting digital release signals on said assigned working channel after successful exchange of said handshake signals and for unmuting communication over the assigned working channel in response to said detected release signals.
Claim 93
Dependent Claim
107 words
A system as in claim 75 wherein said working channel assignment has a certain priority associated therewith and said system further comprises: means for transmitting digital, subaudible new channel assignment updated messages on the assigned working channel, said new channel assignment updated messages having priorities associated therewith; means for monitoring said update messages in each unit, means connected to said monitoring means for detecting the priorities of said monitored update messages, and means connected to said detecting means for responsively dropping off the assigned working channel if the priority associated with a new channel updated message directed to said monitoring means is higher than said certain priority.
Claim 94
Dependent Claim
60 words
A system as in claim 76 wherein: said assigning means includes means for incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting means includes means for transmitting said incremented count value within each of said subaudible updated messages, and means for continually transmitting said subaudible updated messages over said working channel.
Claim 95
Dependent Claim
60 words
A system as in claim 76 wherein: said assigning means includes means for incrementing a subaudible signalling count value each time said working channel is assigned; and said subaudible message transmitting means includes means for transmitting said incremented count value within each of said subaudible updated messages, and means for continually transmitting said subaudible updated messages over said working channel.
Claim 96
Dependent Claim
42 words
A radio unit as in claim 75 further comprising: means for detecting digital channel assignment late entry messages on the control channel to permit the late entry of a called unit to an ongoing working channel communication it was earlier directed to.
Claim 97
Dependent Claim
60 words
A system as in claim 75 further comprising: means for sending, from the calling unit on the assigned working channel, a digital unkeyed message in response to release of a PTT switch, and means responsive to a digital drop signal received on the assigned working channel for dropping off the then-assigned working channel thus freeing it for immediate further assignment.
Claim 98
Independent Claim
87 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the step of: transmitting, with channel assignment signals on at least one of said control channel or an assigned working channel, a trunked status signal identifying whether the usage of the working channel is to be transmission or message trunked.
Claim 99
Independent Claim
87 words
A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the step of: transmitting, with channel assignment signals on at least one of said control channel or an assigned working channel, a trunked status signal identifying whether the usage of the working channel is to be transmission or message trunked.
Claim 100
Dependent Claim
108 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising: transceiver means at a central site for transmitting and receiving radio frequency signals over said control channel and over said working channels; and means for transmitting with channel assignment signals on at least one of said control channel or an assigned working channel, a trunked status signal identifying whether the usage of the working channel is to be transmission or message trunked.
Claim 101
Dependent Claim
108 words
Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising: transceiver means at a central site for transmitting and receiving radio frequency signals over said control channel and over said working channels; and means for transmitting with channel assignment signals on at least one of said control channel or an assigned working channel, a trunked status signal identifying whether the usage of the working channel is to be transmission or message trunked.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-26 | 1993-08-28 | 1994-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-26 | 1997-08-28 | 1998-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-26 | 2001-08-28 | 2002-02-27 | $7700.00 | Window Closed / Lapsed |