EP0713345A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method and apparatus for direct communication in an TDMA radio communication system
Assignee: International Business Machines Corp
•
Filing: 1995-11-16
•
Granted: —
•
Expires: 2015-11-16
Abstract
Abstract Direct communication between a primary portable unit initiating the communication and a secondary portable unit is established utilizing two handshaking operations. The first handshaking operation is performed in the base station channel to establish initial contact between the primary and secondary portable units. After initial contact is made, the second handshaking operation is performed to establish communication in an unoccupied channel. The base station channel and the unoccupied channel may be a TDMA/TDD channel or a TDMA/FDD channel. <IMAGE>
Inventors
- 👤 Trieu Chan Chieu
- 👤 Anand Narasimhan
- 👤 Gary Ernest O'neil
- 👤 Li-Cheng R. Zai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 18:31
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/72; H04M1/725; H04M1/72502; H04M1/72505; H04M1/72513; H04B; H04B7/00; H04B7/24; H04B7/26; H04B7/2643; H04B7/2656; H04M1/72508
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
141 words
In a communication system wherein communication between a base station and user stations occurs over a plurality of radio channels each having time slots, a method for establishing direct communication between user stations comprising the steps of: controlling a first user station to locate a first radio channel within said plurality of radio channels wherein communication of data signals and control signals occurs between said base station and at least one user station, synchronizing said first user station with a first predetermined period of time within said first radio channel during which said base station is not transmitting data and not receiving data; and controlling said first user station to transmit a first calling signal during said first predetermined period of time within said first radio channel to establish direct communication between said first user station and a second user station.
Claim 2
Dependent Claim
25 words
The method of claim 1, wherein said first predetermined period of time is the turn around time between transmitting and receiving of said base station.
Claim 3
Dependent Claim
25 words
The method of claim 1, wherein said first predetermined period of time includes the turn around time between transmitting and receiving of said base station.
Claim 4
Dependent Claim
95 words
The method of claim 1, further comprising the steps of: controlling said second user station to locate said first radio channel; synchronizing said second user station with said first predetermined period of time and a second predetermined period of time within said first radio channel during which the base station is not transmitting data and not receiving data; and controlling said second user station to transmit a first acknowledgement signal during said second predetermined period of time within said first radio channel upon receiving said first calling signal during said first predetermined period of time.
Claim 5
Dependent Claim
25 words
The method of claim 4, wherein said second predetermined period of time is the turn around time between receiving and transmitting of said base station.
Claim 6
Dependent Claim
25 words
The method of claim 4, wherein said second predetermined period of time includes the turn around time between receiving and transmitting of said base station.
Claim 7
Dependent Claim
96 words
The method of claim 4, wherein said first radio channel has a first frequency, and after said first user station receives said first acknowledgement signal transmitted by said second user station, subsequent communication between said first and second user stations occurs over a second radio channel having a second frequency different than said first frequency, wherein communication of data signals and control signals between said base station and at least oneuser station does not occur over said second radio channel, and wherein direct communication between other user stations does not occur over said second radio channel.
Claim 8
Dependent Claim
115 words
The method of claim 4, wherein said first radio channel has a first frequency, further comprising the steps of: upon receiving said first acknowledgement signal, controlling said first user station to locate a second radio channel having a second frequency different than said first frequency, wherein communication of data signals and control Signals between said base station and at least one user station does not occur over said second radio channel, and wherein direct communication between other user stations does not occur over said second radio channel; controlling said first user station to transmit a channel identification signal identifying said second radio channel during said first predetermined period of time within said first radio channel.
Claim 9
Dependent Claim
121 words
The method of claim 4, wherein said first radio channel has a first frequency, further comprising the steps of: upon confirming receipt of said first acknowledgement signal by said first user station, controlling said second user station to locate a second radio channel having a second frequency different than said first frequency, wherein communication of data signals and control signals between said base station and at least one user station does not occur over said second radio channel, and wherein direct communication between other user stations does not occur over said second radio channel; controlling said second user station to transmit a channel identification signal identifying said second radiochannel during said second predetermined period of time within said first radio channel.
Claim 10
Dependent Claim
163 words
The method of claim 1, wherein communication of data signals and control signals from said base station to said at least one user station occurs within said first radio channel having a first frequency, wherein communication of data signals and control signals from said at least one user station to said base station occurs within a second radio channel having a second frequency different than said first frequency, further comprising the steps of: controlling said second user station to locate said first radio channel; synchronizing said second user station with said first predetermined period of time within said first radio channel and a second predetermined period of time within said second radio channel during which the base station is not transmitting data and not receiving data; and controlling said second user station to transmit a first acknowledgement signal during said second predetermined period of time within said second radio channel upon receiving said first calling signal during said first predetermined period of time.
Claim 11
Dependent Claim
121 words
The method of claim 10, wherein after said first user station receives said first acknowledgement signal, subsequent communication from said first user station to said second user stations occurs over a third radio channel having a third frequency different than said first and second frequencies, subsequent communication from said second user station to said first user station occurs over a fourth radio channel having a fourth frequency different than said first, second and third frequencies, wherein communication of data signals and control signals between said base station and at least one user station does not occur over said third and fourth radio channels, and wherein direct communication between other user stations does not occur over said third and fourth radio channels.
Claim 12
Dependent Claim
56 words
The method of claim 11, further comprising the steps of: controlling said first user station to locate said third and fourth radio channels; controlling said first user station to transmit a second calling signal during a third predetermined period of time within said third radio channel, wherein said second calling signal identifies said fourth radio channel.
Claim 13
Dependent Claim
55 words
The method of claim 11, further comprising the steps of: controlling said second user station to locate said third and fourth radio channels; controlling said second user station to transmit a second calling signal during a third predetermined period of time within said fourth radio channel, wherein said second calling signal identifies said third channel.
Claim 14
Dependent Claim
162 words
The method of claim 10, further comprising the steps of: upon receiving said first acknowledgement signal, controlling said first user station to locate third and fourth radio channels, wherein communication from said first user station to said second user station occurs over said third radio channel having a third frequency different than said first and second frequencies, wherein communication from said second user station to said first user station occurs over said fourth radio channel having a fourth frequency different than said first, second and third frequencies, wherein communication of data signals and control signals between said base station and at least one user station does not occur over said third and fourth radio channels, and wherein direct communication between otheruser stations does not occur over said third and fourth radio channels; controlling said first user station to transmit a channel identification signal identifying said third and fourth radio channels during said first predetermined period of time within said first radio channel.
Claim 15
Dependent Claim
171 words
The method of claim 10, further comprising the steps of: upon confirming receipt of said first acknowledgement signal by said first user input station, controlling said second user station to locate third and fourth radio channels, wherein communication from said first user station to said second user station occurs over said third radio channel having a third frequency different than said firstand second frequencies, wherein communication from said second user station to said first user station occurs over said fourth radio channel having a fourth frequency different than said first, second and third frequencies, wherein communication of data signals and control signals between said base station and at least one user station does not occur over said third and fourth radio channels, and wherein direct communication between other user stations does not occur over said third and fourth radio channels; and controlling said second user station to transmit a channel identification signal identifying said third and fourth radio channels during said second predetermined period of time within said second radio channel.
Claim 16
Dependent Claim
85 words
The method of claim 1, wherein each user station is assigned a unique identification number that is associated with one or more group identification numbers, wherein said first user station is assigned a first identification number and said second user station is assigned a second identification number, and wherein the step of controlling said first user station to locate said first radio channel is performed after determining that said first identification number and said second identification number are associated with a common group identification number.
Claim 17
Independent Claim
110 words
An apparatus for use in a communication system wherein communication between a base station and user stations occurs over a plurality of radio channels each having time slots, the apparatus comprising: means for locating a first radio channel within said plurality of radio channels wherein communication of data signals and control signals occurs between said base station and at least one user station, means for synchronizing with a first predetermined period of time within said first radio channel during whichsaid base station is not transmitting data and not receiving data; and means for transmitting a first calling signal during said first predetermined period of time within said first radio channel.
Claim 18
Dependent Claim
25 words
The apparatus of claim 17, wherein said first predetermined period of time is the turn around time between transmitting and receiving of said base station.
Claim 19
Dependent Claim
25 words
The apparatus of claim 17, wherein said first predetermined period of time includes the turn around time between transmitting and receiving of said base station.
Claim 20
Dependent Claim
86 words
An apparatus for use with the apparatus of claim 17, comprising: means for locating said first radio channel; means for synchronizing with said first predetermined period of time and a second predetermined period of time within said first radio channel during which the base station is not transmitting data and not receiving data; and means for transmitting a first acknowledgement signal during said second predetermined period of time within said first radio channel upon receiving said first calling signal during said first predetermined period of time.
Claim 21
Dependent Claim
25 words
The apparatus of claim 20, wherein said second predetermined period of time is the turn around time between receiving and transmitting of said base station.
Claim 22
Dependent Claim
25 words
The apparatus of claim 20, wherein said second predetermined period of time includes the turn around time between receiving and transmitting of said base station.
Claim 23
Independent Claim
149 words
An apparatus for use in a communication system wherein communication between a base station and user stations occurs over a plurality of radio channels each having time slots, wherein communication of data signals and control signals from said base station to said at least one user station occurs within a first radio channel having a first frequency, wherein communication of data signals and control signals from said at least one user station to said base station occurs within a second radio channel having a second frequency different than said first frequency, the apparatus comprising: means for locating said first radio channel; means for synchronizing with a first predetermined period of time within said first radio channel during which said base station is not transmitting data and not receiving data; and means for transmitting a first calling signal during said first predetermined period of time within said first radio channel.
Claim 24
Dependent Claim
86 words
An apparatus for use with the apparatus of claim 23, comprising: means for locating said first radio channel; means for synchronizing with said first predetermined period of time and a second predetermined period of time within said first radio channel during which the base station is not transmitting data and not receiving data; and means for transmitting a first acknowledgement signal during said second predetermined period of time within said first radio channel upon receiving said first calling signal during said first predetermined period of time.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.