Patent US5457680A successfully refreshed from Google Patents.
US5457680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data gateway for mobile data radio terminals in a data communication network
Assignee: International Business Machines Corp
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Filing: 1993-05-18
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Granted: 1995-10-10
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Expires: 2013-05-18
Abstract
Abstract A method is disclosed for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network. In a system of a plurality of base stations (each including a set of cellular telephone voice transceivers), wherein a first and second base stations are coupled through a home mobile data gateway (MDG) to the data communications network and a third base station is coupled through a server mobile data gateway to the data communications network, a method and apparatus which establishes in the home mobile data gateway, a forwarding address to a server mobile data gateway, sends forwarding information from the home mobile data gateway to the server mobile data gateway, and allocates with the server mobile data gateway, a new channel at the third base station, for the mobile data radio terminal. The method further includes determining which base station is providing better signal measurement data and allocating with the home mobile data gateway, a new channel at the better base station, for the mobile data radio terminal. The method further includes allocating an additional channel to the mobile data radio when the forward data packet size is greater than a threshold value. Further in accordance with the invention, when the system receives a forward data packet at the home mobile data gateway from the data communications network, directed to the mobile data radio terminal, it sends the forward data packet to the server mobile data gateway.
Inventors
- 👤 David A. Kamm
- 👤 Stephen T. Parker
- 👤 Merl A. Trimmer, Jr.
- 👤 Sherry L. Trimmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:05
CPC Classifications
H; H04; H04W; H04W8/00; H04W8/02; H04W8/04
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
363 words
A method for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of cellular telephone voice transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, including a first and second base stations coupled through a first mobile data gateway to said data communications network and a third base station coupled through a second mobile data gateway to said data communications network, the method for managing comprising steps of: allocating with said first mobile data gateway, a first channel at said first base station, for the mobile data radio terminal; receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said first mobile data gateway, a forwarding address to said second mobile data gateway, sending forwarding information from said first mobile data gateway to said second mobile data gateway, and allocating with said second mobile data gateway, a new channel at said third base station, for said mobile data radio terminal; and if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said first mobile data gateway, a new channel at said second base station, for said mobile data radio terminal, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway.
Claim 2
Independent Claim
363 words
A method for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of cellular telephone voice transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, including a first and second base stations coupled through a first mobile data gateway to said data communications network and a third base station coupled through a second mobile data gateway to said data communications network, the method for managing comprising steps of: allocating with said first mobile data gateway, a first channel at said first base station, for the mobile data radio terminal; receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said first mobile data gateway, a forwarding address to said second mobile data gateway, sending forwarding information from said first mobile data gateway to said second mobile data gateway, and allocating with said second mobile data gateway, a new channel at said third base station, for said mobile data radio terminal; and if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said first mobile data gateway, a new channel at said second base station, for said mobile data radio terminal, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway.
Claim 3
Dependent Claim
58 words
The method of claim 1, which further comprises: monitoring the size of forward data packets received at said serving mobile data gateway from said data communications network to be sent to said mobile data radio terminal; allocating an additional channel to said mobile data radio terminal when said forward data packet size is greater than a threshold value.
Claim 4
Dependent Claim
64 words
The method of claim 1, which further comprises: monitoring the size of forward data packets received at said serving mobile data gateway from said data communications network to be sent to said mobile data radio terminal; allocating an additional time slot in a channel already allocated to said mobile data radio terminal when said forward data packet size is greater than a threshold value.
Claim 5
Dependent Claim
116 words
The method of claim 1, which further comprises: receiving a forward data packet at said first mobile data gateway from said data communications network, directed to said mobile data radio terminal; determining if said forwarding address exists in said first mobile data gateway, to said second mobile data gateway and if so, sending said forward data packet to said second mobile data gateway; if said forwarding address does not exist, then determining whether said mobile data radio terminal has a channel allocated from either said first base station or said second base station and if so, sending said forward data packet to either said first or second base station determined to have a channel so allocated.
Claim 6
Independent Claim
375 words
A system for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of cellular telephone voice transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, comprising: first and second base stations coupled through a first data gateway to said data communications network; a third base station coupled through a second data gateway to said data communications network; allocating means in said first data gateway, for allocating a first channel at said first base station, for the mobile data radio terminal; storage means in said first data gateway, receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; first determining means in said first data gateway, coupled to said storage means, for determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said first data gateway, a forwarding address to said second data gateway, sending forwarding information from said first data gateway to said second data gateway, and allocating with said second data gateway, a new channel at said third base station, for said mobile data radio terminal; and said first determining means determining if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said first data gateway, a new channel at said second base station, for said mobile data radio terminal, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway.
Claim 7
Independent Claim
375 words
A system for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of cellular telephone voice transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, comprising: first and second base stations coupled through a first data gateway to said data communications network; a third base station coupled through a second data gateway to said data communications network; allocating means in said first data gateway, for allocating a first channel at said first base station, for the mobile data radio terminal; storage means in said first data gateway, receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; first determining means in said first data gateway, coupled to said storage means, for determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said first data gateway, a forwarding address to said second data gateway, sending forwarding information from said first data gateway to said second data gateway, and allocating with said second data gateway, a new channel at said third base station, for said mobile data radio terminal; and said first determining means determining if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said first data gateway, a new channel at said second base station, for said mobile data radio terminal, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway.
Claim 8
Dependent Claim
64 words
The system of claim 5, which further comprises: monitoring means, for monitoring the size of forward data packets received at said serving mobile data gateway from said data communications network to be sent to said mobile data radio terminal; said allocating means, allocating an additional channel to said mobile data radio terminal when said forward data packet size is greater than a threshold value.
Claim 9
Dependent Claim
70 words
The system of claim 5, which further comprises: monitoring means, for monitoring the size of forward data packets received at said serving mobile data gateway from said data communications network to be sent to said mobile data radio terminal; said allocating means, allocating an additional time slot in a channel already allocated to said mobile data radio terminal when said forward data packet size is greater than a threshold value.
Claim 10
Dependent Claim
125 words
The system of claim 5, which further comprises: receiving means, for receiving a forward data packet at said first data gateway from said data communications network, directed to said mobile data radio terminal; second determining means for determining if said forwarding address exists in said first data gateway, to said second data gateway and if so, sending said forward data packet to said second data gateway; and said second determining means determining if said forwarding address does not exist, then determining whether said mobile data radio terminal has a channel allocated from either said first base station or said second base station and if so, sending said forward data packet to either said first or second base station determined to have a channel so allocated.
Claim 11
Independent Claim
339 words
A method for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, including a first and second base stations coupled through a first mobile data gateway to said data communications network and a third base station coupled through a second mobile data gateway to said data communications network, the method for managing comprising steps of: allocating with said first mobile data gateway, a first channel at said first base station, for the mobile data radio terminal; receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said first mobile data gateway, a forwarding address to said second mobile data gateway, sending forwarding information from said first mobile data gateway to said second mobile data gateway, and allocating with said second mobile data gateway, a new channel at said third base station, for said mobile data radio terminal; and if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said first mobile data gateway, a new channel at said second base station, for said mobile data radio terminal.
Claim 12
Independent Claim
339 words
A method for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, including a first and second base stations coupled through a first mobile data gateway to said data communications network and a third base station coupled through a second mobile data gateway to said data communications network, the method for managing comprising steps of: allocating with said first mobile data gateway, a first channel at said first base station, for the mobile data radio terminal; receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said first mobile data gateway, a forwarding address to said second mobile data gateway, sending forwarding information from said first mobile data gateway to said second mobile data gateway, and allocating with said second mobile data gateway, a new channel at said third base station, for said mobile data radio terminal; and if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said first mobile data gateway, a new channel at said second base station, for said mobile data radio terminal.
Claim 13
Independent Claim
348 words
A system for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, comprising: first and second base stations coupled through a home data gateway to said data communications network; a third base station coupled through a server data gateway to said data communications network; allocating means in said home data gateway, for allocating a first channel at said first base station, for the mobile data radio terminal; storage means in said home data gateway, receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining means in said home data gateway, coupled to said storage means, for determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said home data gateway, a forwarding address to said server data gateway, sending forwarding information from said home data gateway to said server data gateway, and allocating with said server data gateway, a new channel at said third base station, for said mobile data radio terminal; and said determining means determining if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said home data gateway, a new channel at said second base station, for said mobile data radio terminal.
Claim 14
Independent Claim
348 words
A system for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, comprising: first and second base stations coupled through a home data gateway to said data communications network; a third base station coupled through a server data gateway to said data communications network; allocating means in said home data gateway, for allocating a first channel at said first base station, for the mobile data radio terminal; storage means in said home data gateway, receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining means in said home data gateway, coupled to said storage means, for determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said home data gateway, a forwarding address to said server data gateway, sending forwarding information from said home data gateway to said server data gateway, and allocating with said server data gateway, a new channel at said third base station, for said mobile data radio terminal; and said determining means determining if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said home data gateway, a new channel at said second base station, for said mobile data radio terminal.
Claim 15
Independent Claim
456 words
A method for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of cellular telephone voice transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, including a first and second base stations coupled through a home mobile data gateway to said data communications network and a third base station coupled through a server mobile data gateway to said data communications network, each base station further including at least one data transceiver, and a set of sensors coupled to each voice transceiver in said set of voice transceivers, the method for managing comprising steps of: determining in said first base station, when it is safe to switch said data transceiver onto a first channel to which a particular one of the voice transceivers in said set of voice transceivers is tuned; allocating with said home mobile data gateway, said first channel at said first base station, for the mobile data radio terminal; receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said home mobile data gateway, a forwarding address to said server mobile data gateway, sending forwarding information from said home mobile data gateway to said server mobile data gateway, and allocating with said server mobile data gateway, a new channel at said third base station, for said mobile data radio terminal; if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said home mobile data gateway, a new channel at said second base station, for said mobile data radio terminal, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway; and determining in said first base station, when to turn off said data transceiver based on sensing a demand for said first channel by said particular one of the voice transceivers.
Claim 16
Independent Claim
456 words
A method for managing the communication of data packets between a mobile data radio terminal and a plurality of fixed base stations in a data communications network, in which each base station includes a set of cellular telephone voice transceivers, each tuned to one of a preselected set of communication channels, and means for coupling each transceiver in said set of transceivers to an antenna to facilitate the performance of duplex radio terminal communications over said set of channels with said mobile data radio terminal within range of at least one of said fixed base stations, including a first and second base stations coupled through a home mobile data gateway to said data communications network and a third base station coupled through a server mobile data gateway to said data communications network, each base station further including at least one data transceiver, and a set of sensors coupled to each voice transceiver in said set of voice transceivers, the method for managing comprising steps of: determining in said first base station, when it is safe to switch said data transceiver onto a first channel to which a particular one of the voice transceivers in said set of voice transceivers is tuned; allocating with said home mobile data gateway, said first channel at said first base station, for the mobile data radio terminal; receiving a data packet from said mobile data radio terminal, including first signal strength measurement data for said first base station, second signal strength measurement data for said second base station and third signal strength measurement data for said third base station; determining if said third signal strength measurement data is better than said first signal strength measurement data and said second signal strength measurement data and if so, establishing in said home mobile data gateway, a forwarding address to said server mobile data gateway, sending forwarding information from said home mobile data gateway to said server mobile data gateway, and allocating with said server mobile data gateway, a new channel at said third base station, for said mobile data radio terminal; if said third signal strength measurement data is not better than said second signal strength measurement data, then determining if said second signal strength measurement data is better than said first signal strength measurement data and if so, allocating with said home mobile data gateway, a new channel at said second base station, for said mobile data radio terminal, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway; and determining in said first base station, when to turn off said data transceiver based on sensing a demand for said first channel by said particular one of the voice transceivers.
Claim 17
Dependent Claim
58 words
The method of claim 11, which further comprises: monitoring the size of forward data packets received at said serving mobile data gateway from said data communications network to be sent to said mobile data radio terminal; allocating an additional channel to said mobile data radio terminal when said forward data packet size is greater than a threshold value.
Claim 18
Dependent Claim
64 words
The method of claim 11, which further comprises: monitoring the size of forward data packets received at said serving mobile data gateway from said data communications network to be sent to said mobile data radio terminal; allocating an additional time slot in a channel already allocated to said mobile data radio terminal when said forward data packet size is greater than a threshold value.
Claim 19
Dependent Claim
116 words
The method of claim 11, which further comprises: receiving a forward data packet at said home mobile data gateway from said data communications network, directed to said mobile data radio terminal; determining if said forwarding address exists in said home mobile data gateway, to said server mobile data gateway and if so, sending said forward data packet to said server mobile data gateway; if said forwarding address does not exist, then determining whether said mobile data radio terminal has a channel allocated from either said first base station or said second base station and if so, sending said forward data packet to either said first or second base station determined to have a channel so allocated.
Claim 20
Dependent Claim
51 words
The method of claim 14 which further comprises: receiving in said home mobile data gateway a demand to conduct a ZAP operation or discard all input from or to said mobile radio terminal on said first channel; performing the ZAP operation in said home mobile data gateway on said first channel.
Claim 21
Dependent Claim
41 words
The method of claim 14 which further comprises: periodically requesting by said home mobile data gateway RF sniffing data OR ANALOG SIGNAL ACTIVITY from said first base station by transmitting a REQUEST RF MONITORING DATA PACKET to said first base station.
Claim 22
Dependent Claim
29 words
The method of claim 16 which further comprises: said home mobile data gateway sending to said first base station said REQUEST RF MONITORING DATA PACKET as a heartbeat signal.
Claim 23
Dependent Claim
29 words
The method of claim 14 which further comprises: said home mobile data gateway sending to said first base station a REQUEST RF MONITORING DATA PACKET as a heartbeat signal.
Claim 24
Dependent Claim
29 words
The method of claim 14 which further comprises: said home mobile data gateway sending to staid first base station an ADD LOGICAL CHANNEL packet to add a logical channel.
Claim 25
Dependent Claim
29 words
The method of claim 14 which further comprises: said home mobile data gateway sending to said first base station a DELETE LOGICAL CHANNEL packet to delete a logical channel.
Claim 26
Dependent Claim
38 words
The method of claim 14 which further comprises: said home mobile data gateway sending to said first base station an MOBILE DATA BASE STATION (MDBS) DATA PAUSE PACKET to cause said first base station to pause data transmission.
Claim 27
Dependent Claim
34 words
The method of claim 14 which further comprises: said home mobile data gateway sending to said first base station an MDBS DATA RESUME PACKET to cause said first base station to resume data transmission.
Claim 28
Dependent Claim
33 words
The method of claim 14 which further comprises: said home mobile data gateway sending to said first base station an ADJACENT MDBS CHANNEL UTILIZATION packet to obtain information from said first base station.
Claim 29
Dependent Claim
35 words
The method of claim 14 which further comprises: said home mobile data gateway sending to said first base station an CHANNEL SELECTION RESPONSE packet to response to a channel selection by said first base station.
Claim 30
Dependent Claim
28 words
The method of claim 14 which further comprises: said home mobile data gateway receiving from said first base station a REVERSE CHANNEL STATUS packet specifying a free slot.
Claim 31
Independent Claim
142 words
A system for managing data packets between a mobile radio terminal and a plurality of base stations in a communications network comprising: a first mobile data gateway coupling a first and second base station to the network; a second mobile data gateway coupling a third base station to the network; means for sending a forwarding address from the first mobile data gateway to the second mobile data gateway for allocating with the second mobile data gateway a new channel at the third base station for the mobile data radio terminal; and means for further allocating the new channel among the base stations according to a comparison of a signal strength measurement for each base station included in the data packet, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway.
Claim 32
Independent Claim
142 words
A system for managing data packets between a mobile radio terminal and a plurality of base stations in a communications network comprising: a first mobile data gateway coupling a first and second base station to the network; a second mobile data gateway coupling a third base station to the network; means for sending a forwarding address from the first mobile data gateway to the second mobile data gateway for allocating with the second mobile data gateway a new channel at the third base station for the mobile data radio terminal; and means for further allocating the new channel among the base stations according to a comparison of a signal strength measurement for each base station included in the data packet, the mobile data gateway coupled to the base station receiving the strongest signal strength being defined as the serving mobile data gateway.
Claim 33
Dependent Claim
31 words
The system of claim 26 further including means for tracking the amount of packet data which has been sent to and received from the network by the mobile radio data terminal.
Claim 34
Dependent Claim
44 words
The system of claim 26 further including means for monitoring the size of data packets received at the serving mobile data gateway for the mobile data radio terminal and allocating an additional channel when the data packet size is greater than a threshold value.
Claim 35
Dependent Claim
61 words
The system of claim 26 further including means for determining if the data packet from the network has a forwarding address in the first mobile data gateway for the second mobile data gateway, and (i) if so, sends the data packet to the second mobile data gateway, and (ii) if not, sends the data packet to the serving mobile data gateway.
Claim 36
Dependent Claim
25 words
The system of claim 26 further including means for accurately billing a user of a mobile data radio terminal based upon use of the network.
Claim 37
Dependent Claim
37 words
The system of claim 26 further including means for ensuring that only the packet data received from and transmitted to the mobile data radio terminal for a subscriber is properly routed to and received from the subscriber.
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USPTO Annuity & Maintenance Windows
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| 3.5 Years (Year 4) | 1998-10-09 | 1999-04-10 | 1999-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-09 | 2003-04-10 | 2003-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-09 | 2007-04-10 | 2007-10-10 | $7700.00 | Window Closed / Lapsed |