Methods of communicating over time-division multiple-access (TDMA) communication systems with distinct non-time-critical and time-critical network management information transmission rates

• US 6,587,443 B1
• Filed: 04/28/1999
• Issued: 07/01/2003
• Est. Priority Date: 09/30/1996
• Status: Expired due to Term

• Current Assignee: ATC Technology Corporation (FedEx Corporation)
• Original Assignee: Mobile Satellite Venture LP
• Inventors: Dutta, Santanu
• Primary Examiner(s): HSU, ALPUS
• Application Number:
  US09/300,422
• Time in Patent Office: 1,525 Days
• Field of Search: 370/280, 370/321, 370/329, 370/337, 370/347, 370/349, 370/442, 370/465, 370/468, 370/522, 455/12.1, 455/13.1, 455/428, 455/430, 455/450, 455/453, 455/507, 455/509, 455/511, 455/515, 455/517, 455/67.1
• US Class Current: 370/322
• CPC Class Codes: H04B 7/18532 Arrangements for managing transmission, i.e. for transporting data or a signalling message
• CPC Class Codes: H04B 7/212 Time-division multiple access [TDMA]

Abstract

Data transfer efficiencies of a frequency division and/or time division multiple access (FDMA/TDMA) communication systems are improved over prior art systems by distributing signalling and messaging activities over all return channels of a channel group, by varying forward to return channel data rate ratios, and by reducing message transport delays with respect to prior art communication systems, based on message traffic over such channel group. Return channels of a defined channel group are time division controlled and are generic to operate either in a signalling mode or in a messaging mode. Data rates for the forward channel and the return channels may be selected from predefined combinations of forward and return channel data rates. Message transport delays are reduced over prior art delay periods by reducing the frame lengths of data frames transmitted at a specified frame rate over the forward channel and by transmitting network management data other than time-critical data reception results and time slot allocations periodically at a superframe rate which is less than the frame rate.

Claims

1. In method of communicating over a channel group of a communication system wherein a central station transmits to a plurality of terminals over a forward channel, and transmissions by at least one of the plurality of terminals to the central station occur over a return channel of the channel group, a method comprising the step of transmitting by the at least one of the plurality of terminals data to the central station at a data rate that is automatically set by a network management message received over the forward channel by the at least one of the plurality of terminals from the central station;

wherein the data includes a return channel descriptor packet (RCDP) describing slot allocations of the return channels of a channel group that are in-use, and

wherein as a number of the at least one of the plurality of return channels in-use in the channel group vary based on traffic conditions in the channel group, a length of the RCDP also varies.

2. The method of communicating according to claim 1, wherein the RCDP includes data that replaces separate signalling channel descriptor packets for each active signalling channel of a channel group.