Dual mode satellite/cellular terminal

• US 5,757,787 A
• Filed: 03/11/1997
• Issued: 05/26/1998
• Est. Priority Date: 07/12/1995
• Status: Expired due to Fees

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Dent, Paul W.
• Primary Examiner(s): Safourek, Benedict V.
• Application Number:
  US08/816,047
• Time in Patent Office: 441 Days
• Field of Search: 455/450, 455/452, 455/453, 455/509, 455/517, 370/229, 370/235, 370/280, 370/329, 370/330, 370/337, 370/343, 370/347, 370/348, 370/436, 370/468, 370/478
• US Class Current: 370/330
• CPC Class Codes: H04B 1/408 the transmitter oscillator frequency being identical to the receiver local oscillator frequency
• CPC Class Codes: H04B 7/18532 Arrangements for managing transmission, i.e. for transporting data or a signalling message
• CPC Class Codes: H04B 7/18563 Arrangements for interconnecting multiple systems data switching networks H04L12/00
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0059 Convolutional codes
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04W 52/06 TPC algorithms
• CPC Class Codes: H04W 52/08 Closed loop power control
• CPC Class Codes: H04W 52/10 Open loop power control
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/287 when the channel is in stand-by
• CPC Class Codes: H04W 52/288 taking into account the usage mode, e.g. hands-free, data transmission, telephone
• CPC Class Codes: H04W 52/30 using constraints in the total amount of available transmission power
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A method and apparatus of communicating information using Time Division Multiple Access and adaptive transmission and reception are disclosed. Signal bursts are transmitted from TDMA transmitters to a TDMA receiver wherein the transmitter codes the information and transmits coded information to the receiver using at least one of two timeslots of a plurality of timeslots in a repetitive TDMA frame period. Both of the two timeslots are received whether or not the transmitter has transmitted using one or two timeslots and the received signals are classified as intended and non-intended. Successively received signals classified as intended are then assembled into a block for decoding to reproduce the information.

Claims

1. A time division multiple access format for transmitting traffic and signalling data between a network station and a plurality of remote stations, comprising the steps of:

dividing a superframe period into an odd number of TDMA frame periods;

dividing each TDMA frame period into an even number of timeslots;

using said even number of timeslots in one of said odd number of TDMA frames for transmitting signalling information addressed respectively to a corresponding even number of remote stations and the remaining TDMA frames in said superframe for transmitting traffic information;

dividing said remaining number of frames used for transmitting traffic information into a first group of traffic frames and a second group of traffic frames; and

using said even number of timeslots in said first group of traffic frames to transmit traffic data to a corresponding even number of remote stations and using the timeslots in said second group of traffic frames to transmit data to a corresponding number of other remote stations.

2. A method according to claim 1, wherein said signalling information comprises an indication whether said information is addressed to one of said remote stations for which traffic information was transmitted using a timeslot from each of said first group of traffic frames or for one of said remote stations for which traffic information was sent using a timeslot in said second group of traffic frames.

3. An adaptive time division multiple access format for transmitting traffic and signalling data between a network station and a plurality of remote stations, comprising the steps of:

dividing a superframe period into an odd number of TDMA frame periods;

dividing each TDMA frame period into an even number of timeslots;

using said even number of timeslots in one of said odd number of TDMA frames for transmitting signalling information to said remote stations and the remaining TDMA frames in said superframe for transmitting traffic information;

dividing said remaining number of frames used for transmitting traffic information into a first group of traffic frames and a second group of traffic frames; and

using one of said even number of timeslots in said first group of traffic frames to transmit traffic data to a first of said remote stations and using the corresponding timeslot in said second group of traffic frames to transmit data to another remote station alternatively in dependence on communications signal quality using both said timeslot in said first group of frames and said corresponding timeslot in said second group of frames for communicating with the same remote station.

4. An improved method of capacity allocation in a TDMA satellite or cellular communications system comprising a number of areas containing mobile subscriber terminals each area being served by a respective antenna beam, said method comprising the steps of:

allocating each mobile terminal in each area a timeslot in a each TDMA frame period and a channel frequency in a frequency set for receiving data whereby mobiles in the same area receive different timeslot and frequency allocations and mobiles in different areas may share the same timeslot and frequency allocation;

transmitting coded information bits to a mobile terminal in a given area using a respectively allocated timeslot in every one of said TDMA frame periods when the total number of mobiles so served in said given area is similar to the number of mobiles served in surrounding areas and close to a mean number of mobiles expected in each area; and

transmitting coded information bits to a mobile terminal in a given area using a respectively allocated timeslot in every alternate one of said TDMA frame periods and using the corresponding timeslot in the other half of the frame periods for transmitting coded information to a different mobile terminal when the number of mobiles so served in said given area is substantially greater than said mean value and the number of mobiles served in adjacent areas is on average less than said mean value.