Multiplex communications – Communication over free space – Combining or distributing information via code word channels...
Patent
1995-09-05
1997-10-28
Chin, Wellington
Multiplex communications
Communication over free space
Combining or distributing information via code word channels...
370348, 370349, H04L 1256
Patent
active
056823827
ABSTRACT:
A scalable, self-organizing packet radio network providing decentralized collision-free packet transfer is disclosed having spread-spectrum transmitters and receivers for eliminating contention from background noise, spread-spectrum receivers with multiple tracking and despreading channels for eliminating contention from multiple transmitters contending for the same receiver at the same time, and a processor implemented scheduling technique for eliminating contention arising both from self-contention and from comparatively-high power transmissions of neighboring stations. In the preferred embodiments, the processor implemented scheduling technique randomly provides a unique schedule of transmit and receive opportunities for each station. In accord therewith, each station obliges itself to listen and publishes the unique schedule of each station to every neighboring station. To avoid self-contention, a packet is transmitted to an intended station at a time that corresponds to the first available listening opportunity thereof that is long enough to receive the packet. To avoid contention arising from comparatively-high power transmissions of neighboring stations, a packet is transmitted to an intended station at a time that corresponds to the first available transmit opportunity thereof that does not overlap with the receive windows of any neighboring station. In the preferred embodiments, a processor implemented power control technique is disclosed which so varies transmitter power as to provide a fixed level of power at any intended recipient station. In the preferred embodiments, minimum energy routing is employed for specifying intended stations for multi-hop packet transfer. In the presently preferred embodiments, the random generation at each station of its unique schedule is implemented by a pseudo-random schedule generator common to all stations and by a pseudo-random clock unique to each station. In the presently preferred embodiment, neighboring stations periodically exchange rendezvous packets that include information representative of each station's pseudo-random clock, transmitted power and station identity.
REFERENCES:
patent: 5136612 (1992-08-01), Bi
patent: 5224122 (1993-06-01), Bruckert
patent: 5394434 (1995-02-01), Kawabe et al.
patent: 5459758 (1995-10-01), Moore, III
patent: 5463660 (1995-10-01), Fukasawa et al.
"Evaluation of a Distributed TDMA Rescheduling Procedure for Mobile Packet Radio Networks", by Stevens et al., MILCOM '91, (pp. 1167-1171, 1991).
"Throughout Enhancement of Direct-Sequence Spread-Spectrum Packet Radio Networks by Adaptive Power Control," Sheikh et al., appearing at IEEE Trans. Commun., vol. Com-42 No. 2/3/4 (pp. 884-890, Feb./Mar./Apr. 1994).
"Making Transmission Schedules Immune to Topology Changes in Multi-Hop Packet Radio Networks," Chlamtac et al., appearing at IEEE International Conference On Communications '93 (pp.1854-1858, 1993).
"Traffic Sensitive Algorithms and Performance Measures for the Generation of Self-Organizing Radio Network Schedules," Shor et al., appearing at IEEE Trans. Commun., vol. Com-41 No. 1. (pp. 16-21, Jan. 1993).
Data Networks, by Demitri Bertsekas and Robert Gallager, (pp. 274-282, Prentice-Hall, 1987).
Spectral Efficiency Considerations for Packet Radio, Phil Karn, appearing at 10th Computer Networking Conference, (pp. 62-66, 1991).
The Throughput of Packet Broadcasting Channels, Norman Abramson, appearing at IEEE Trans. Commun., vol. Com-25 No. 1 (pp.117-128, Jan. 1977).
Crosslink Architectures for a Multiple Satellite System, Binder et al., appearing at Proceedings of the IEEE, vol. 75, No. 1, (pp. 74-82, Jan. 1987).
Chin Wellington
Durigon Albert Peter
Hyun Soon D.
Massachusetts Institute of Technology
LandOfFree
Scalable, self-organizing packet radio network having decentrali does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Scalable, self-organizing packet radio network having decentrali, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Scalable, self-organizing packet radio network having decentrali will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1030470