US5261118A
Expired / Lapsed
US
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Simulcast synchronization and equalization system and method therefor
Assignee: Motorola Solutions Inc
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Filing: 1991-10-04
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Granted: 1993-11-09
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Expires: 2011-10-04
Abstract
Abstract A control station 12 initiates a system timing signal transmission which is re-transmitted from a satellite 14. In response to receiving the system timing signal, the control station 12 then generates a time correction factor which is distributed to a plurality of transmission stations 16, 18. The transmission stations 16, 18 in response to receiving the system timing signal transmission and the time correction factor distributed from the control station 12 generate a time adjustment factor which is used to correct the local transmission clocks 36, 36', thereby providing time synchronization of data transmissions generated from the transmission stations 16, 18.
Inventors
- 👤 II Jan P. Vanderspool
- 👤 Steven A. Goreham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:58
CPC Classifications
H; H04; H04B; H04B7/00; H04H; H04H20/00; H04H20/65; H04H20/67
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
166 words
A simulcast transmission system having means for time synchronizing the transmission of data signals therefrom, comprising: a control station comprising first time generating means for generating system timing signals and for transmitting the same, means for receiving the transmitted system timing signals, means for comparing the transmitted and received system timing signals to generate a time correction factor signal in response thereto, and means for distributing the time correction factor signal to a plurality of transmission stations; and each of said plurality of transmission stations comprising second time generating means for generating local timing signals, means responsive to local timing signals for transmitting the data signals, means for receiving the transmitted system timing signals, means for receiving the time correction factor signal, means for comparing the received system timing signals and time correction factor signal with the local timing signals to generate a time adjustment factor signal, and means responsive to the time adjustment factor signal for adjusting the timing of said second time generating means.
Claim 2
Dependent Claim
166 words
A simulcast transmission system having means for time synchronizing the transmission of data signals therefrom, comprising: a control station comprising first time generating means for generating system timing signals and for transmitting the same, means for receiving the transmitted system timing signals, means for comparing the transmitted and received system timing signals to generate a time correction factor signal in response thereto, and means for distributing the time correction factor signal to a plurality of transmission stations; and each of said plurality of transmission stations comprising second time generating means for generating local timing signals, means responsive to local timing signals for transmitting the data signals, means for receiving the transmitted system timing signals, means for receiving the time correction factor signal, means for comparing the received system timing signals and time correction factor signal with the local timing signals to generate a time adjustment factor signal, and means responsive to the time adjustment factor signal for adjusting the timing of said second time generating means.
Claim 3
Dependent Claim
37 words
The simulcast transmission system according to claim 1, wherein said first time generating means comprises: means for generating frequency reference signals; and master clock means, responsive to the frequency reference signals for generating the system timing signals.
Claim 4
Dependent Claim
37 words
The simulcast transmission system according to claim 1, wherein said second time generating means comprises: means for generating frequency reference signals; and local clock means, responsive to the frequency reference signals for generating the local timing signals.
Claim 5
Dependent Claim
61 words
The simulcast transmission system according to claim 1, wherein said means for transmitting the system timing signals comprises: satellite up-link transmitter means for transmitting the system timing signals to a satellite, said satellite having satellite receiving means for receiving the transmitted system timing signals, and satellite transmitter means, coupled to said satellite receiving means, for re-transmitting the received system timing signals.
Claim 6
Dependent Claim
28 words
The simulcast transmission system according to claim 4, wherein said means for transmitting the system timing signals further transmits the data signals and data transmission start time signals.
Claim 7
Dependent Claim
23 words
The simulcast transmission system according to claim 1, wherein said means for comparing the transmitted and received system timing signals comprises a microcomputer.
Claim 8
Dependent Claim
74 words
The simulcast transmission system according to claim 6, wherein the time correction factor signal includes a time correction factor value calculated by said microcomputer using T.sub.cf =T.sub.rec -T.sub.xmit where T cf is the time correction factor value, T rec is a second time value corresponding to the time of reception of the system timing signals, and T xmit is a first time value corresponding to the time of transmission of the system timing signals.
Claim 9
Dependent Claim
31 words
The simulcast transmission system according to claim 1, wherein said means for comparing the received system timing signals and time correction factor signal with the local timing signals comprises a microcomputer.
Claim 10
Dependent Claim
91 words
The simulcast transmission system according to claim 8, wherein the time adjustment factor signal includes a time adjustment factor value calculated by said microcomputer using T.sub.adjN =(T.sub.xmit +T.sub.cf)-T.sub.recN where T adjN is the time adjustment factor value for an Nth transmission station, T xmit is the first time value corresponding to the time of transmission of the system timing signals, T cf is the time correction factor value, and T recN is a time value corresponding to the time of reception of the system timing signals at the Nth transmission station.
Claim 11
Dependent Claim
58 words
The simulcast transmission system according to claim 1, wherein the system timing signals include at least timing information corresponding to a predetermined time for the transmission of the data signals from said plurality of transmission stations and synchronization signals which include at least synchronization information identifying a predetermined time mark and data signal transmission time information corresponding thereto.
Claim 12
Dependent Claim
15 words
The simulcast transmission system according to claim 10, wherein the synchronization signals re periodically generated.
Claim 13
Dependent Claim
69 words
The simulcast transmission system according to claim 1, wherein said means for adjusting the timing of said second time generating means comprises: means for storing a time adjustment factor value derived by comparing the received system timing signals and time correction factor signal with the local timing signals; converter means, coupled to said storing means, for converting the stored time adjustment factor value into the time adjustment factor signal.
Claim 14
Dependent Claim
40 words
The simulcast transmission system according to claim 12, wherein said time adjustment factor value is a digital information sequence, and wherein said converter means converts the digital information sequence into an analog signal corresponding to the time adjustment factor signal.
Claim 15
Dependent Claim
56 words
The simulcast transmission system according to claim 1, wherein said transmissions stations further comprise means for storing a distance correction factor signal, and said means for comparing compares the received system timing signals and time correction factor signal with the local timing signals and a distance correction factor signal to generate the time adjustment factor signal.
Claim 16
Dependent Claim
39 words
The simulcast transmission system according to claim 14, wherein said transmissions station further comprises memory means for storing information, and wherein the distance correction factor signal includes a distance correction factor value which is stored in said memory means.
Claim 17
Dependent Claim
37 words
The simulcast transmission system according to claim 15, wherein said means for comparing the received system timing signals and time correction factor signal with the local timing signals and a distance correction factor signal comprises a microcomputer.
Claim 18
Dependent Claim
112 words
The simulcast transmission system according to claim 16, wherein the time adjustment factor signal includes a time adjustment factor value calculated by said microcomputer using T.sub.adjN =(T.sub.xmit +T.sub.cf)+T.sub.distN -T.sub.recN where T adjN is the time adjustment factor value for an Nth transmission station, T xmit is the first time value corresponding to the time of transmission of the system timing signals, T cf is the time correction factor value, T distN is the distance correction factor value corresponding to the distance between said satellite and said Nth transmission station, and T recN is a time value corresponding to the time of reception of the system timing signals at the Nth transmission station.
Claim 19
Dependent Claim
149 words
A transmission station for use in a simulcast transmission system comprising a plurality of transmission stations which are capable of providing simulcast transmission of data signals, the simulcast transmission system having a control station which is capable of generating system timing signals, and in response thereto generating a time correction factor signal, and for distributing the time correction factor signal to the plurality of transmission stations, said transmission station comprising: time generating means for generating local timing signals: means, responsive to local timing signals, for transmitting the data signals; means for receiving the transmitted system timing signals; means for receiving the time correction factor signal; means for comparing the received system timing signals and the time correction factor signal with the local timing signals to generate a time adjustment factor signal; and means responsive to the time adjustment factor signal for adjusting the timing of said time generating means.
Claim 20
Dependent Claim
149 words
A transmission station for use in a simulcast transmission system comprising a plurality of transmission stations which are capable of providing simulcast transmission of data signals, the simulcast transmission system having a control station which is capable of generating system timing signals, and in response thereto generating a time correction factor signal, and for distributing the time correction factor signal to the plurality of transmission stations, said transmission station comprising: time generating means for generating local timing signals: means, responsive to local timing signals, for transmitting the data signals; means for receiving the transmitted system timing signals; means for receiving the time correction factor signal; means for comparing the received system timing signals and the time correction factor signal with the local timing signals to generate a time adjustment factor signal; and means responsive to the time adjustment factor signal for adjusting the timing of said time generating means.
Claim 21
Dependent Claim
38 words
The transmission station according to claim 18, wherein said time generating means comprises: frequency reference generating means for generating frequency reference signals; and local clock means, responsive to the frequency reference signals for generating the local timing signals.
Claim 22
Dependent Claim
24 words
The transmission station according to claim 19, wherein said means for transmitting the data signals transmits the data signals at a predetermined transmission frequency.
Claim 23
Dependent Claim
20 words
The transmission station according to claim 20, wherein the predetermined transmission frequency is established by the frequency reference signals generated.
Claim 24
Dependent Claim
31 words
The transmission station according to claim 18, wherein said means for comparing the received system timing signals and the time correction factor signal with the local timing signals comprises a microcomputer.
Claim 25
Dependent Claim
86 words
The transmission station according to claim 22, wherein the time adjustment factor signal includes a time adjustment factor value calculated by T.sub.adj =(T.sub.xmit +T.sub.cf)-T.sub.rec where T adj is the time adjustment factor value calculated for the transmission station, T xmit is the first time value corresponding to the time of transmission of the system timing signals, T cf is the time correction factor value, and T rec is a time value corresponding to the time of reception of the system timing signals at the transmission station.
Claim 26
Dependent Claim
52 words
The transmission station according to claim 18, wherein the system timing signals include at least timing information corresponding to a predetermined time for data signal transmission from said transmission station and synchronization signals which include at least synchronization information identifying a predetermined time mark and data signal transmission time information corresponding thereto.
Claim 27
Dependent Claim
49 words
The transmission station according to claim 23, wherein said means for adjusting the timing of said time generating means comprises: means for storing the time adjustment factor value; converter means, coupled to said storing means, for converting the stored time adjustment factor value into the time adjustment factor signal.
Claim 28
Dependent Claim
39 words
The transmission station according to claim 25, wherein said time adjustment factor value is a digital information sequence, and wherein said converter means converts the digital information sequence into an analog signal corresponding to the time adjustment factor signal.
Claim 29
Dependent Claim
51 words
The transmission station according to claim 18 further comprising means for storing a distance correction factor signal, and said means for comparing compares the received system timing signals and time correction factor signal with the local timing signals and a distance correction factor signal to generate the time adjustment factor signal.
Claim 30
Dependent Claim
34 words
The transmission station according to claim 27 further comprising memory means for storing information, and wherein the distance correction factor signal includes a distance correction factor value which is stored in said memory means.
Claim 31
Dependent Claim
37 words
The transmission station according to claim 28, wherein said means for comparing the received system timing signals and the time correction factor signal with the local timing signals and the distance correction factor signal comprises a microcomputer.
Claim 32
Dependent Claim
105 words
The transmission station according to claim 29, wherein the time adjustment factor signal includes a time adjustment factor value calculated by T.sub.adj =(T.sub.xmit +T.sub.cf)+T.sub.dist -T.sub.rec where T adj is the time adjustment factor value for said transmission station, T xmit is the first time value corresponding to the time of transmission of the system timing signals, T cf is the time correction factor value, T dist is the distance correction factor value corresponding to the distance between said satellite and said transmission station, and T rec is a time value corresponding to the time of reception of the system timing signals at said transmission station.
Claim 33
Independent Claim
127 words
A method of time synchronizing data signal transmissions originating from a plurality of transmission stations operating within a simulcast transmission system, the transmission stations having transmission clocks for controlling the starting time of the data signal transmissions, said method comprising the step of: generating, at a control station, a time correction factor signal in response to the control station generating and transmitting a system timing signal; distributing the system timing signal and the time correction factor signal from the control station to the transmission stations; generating, at the transmission stations, local time adjustment factor signals in response to receiving the system timing signal and the time correction factor signal; adjusting the transmission clocks at the transmission stations in response to the local time adjustment factor signals generated.
Claim 34
Independent Claim
127 words
A method of time synchronizing data signal transmissions originating from a plurality of transmission stations operating within a simulcast transmission system, the transmission stations having transmission clocks for controlling the starting time of the data signal transmissions, said method comprising the step of: generating, at a control station, a time correction factor signal in response to the control station generating and transmitting a system timing signal; distributing the system timing signal and the time correction factor signal from the control station to the transmission stations; generating, at the transmission stations, local time adjustment factor signals in response to receiving the system timing signal and the time correction factor signal; adjusting the transmission clocks at the transmission stations in response to the local time adjustment factor signals generated.
Claim 35
Dependent Claim
116 words
The method of time synchronizing data signal transmissions according to claim 31 wherein said step of generating a time correction factor signal at the control station comprises the steps of: transmitting, from the control station, the system timing signal which includes at least a timing word which provides a time mark indicating a time of transmission of the system timing signal; receiving the system timing signal including the timing word at the control station to detect the time of reception of the system timing signal; and comparing the time of reception of the system timing signal with the time of transmission of the system timing signal to determine a value for the time correction factor signal.
Claim 36
Dependent Claim
86 words
The method of time synchronizing data signal transmissions according to claim 32, wherein said step of comparing comprises the step of calculating a value for the time correction factor signal according to the formula T.sub.cf =T.sub.rec -T.sub.xmit where T cf is the value for the time correction factor signal, T rec is a second time value corresponding to the time of reception of the system timing signal, and T xmit is a first time value corresponding to the time of transmission of the system timing signal.
Claim 37
Dependent Claim
82 words
The method of time synchronizing data signal transmissions according to claim 32 wherein said step of generating a time adjustment factor signal comprises the steps of: receiving the system timing signal including the timing word at the transmission station to detect the local time of reception of the timing word; and comparing the local time of reception with the time of transmission of the system timing signal and the time correction factor to determine a value for the time adjustment factor signal.
Claim 38
Dependent Claim
109 words
The method of time synchronizing data signal transmissions according to claim 34, wherein said step of comparing comprises the step of calculating the value for the time adjustment factor signal according to the formula T.sub.adjN =(T.sub.xmit +T.sub.cf)-T.sub.recN where T adjN is the value for the time adjustment factor signal for an Nth transmission station, T xmit is the first time value corresponding to the time of transmission of the system timing signals, T cf is a time value corresponding to the received time correction factor signal, and T recN is a time value corresponding to the time of reception of the system timing signals at the Nth transmission station.
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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) | 1996-11-08 | 1997-05-10 | 1997-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-08 | 2001-05-10 | 2001-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-08 | 2005-05-10 | 2005-11-09 | $7700.00 | Window Closed / Lapsed |