Pulse or digital communications – Systems using alternating or pulsating current – Plural channels for transmission of a single pulse train
Reexamination Certificate
1998-04-15
2001-11-13
Tse, Young T. (Department: 2634)
Pulse or digital communications
Systems using alternating or pulsating current
Plural channels for transmission of a single pulse train
C375S347000, C375S299000
Reexamination Certificate
active
06317466
ABSTRACT:
TECHNICAL FIELD
The invention relates to a wireless communications system employing Multi-Element Antennas (MEAs) at both the transmitter and receiver.
BACKGROUND OF THE INVENTION
The transmission capacity (ultimate bit rate) of a digital wireless communications system is based on a number of different parameters including (a) total radiated power at the transmitter, (b) the number of antenna elements at the transmitter and receiver, (c) noise power at the receiver, (d) characteristics of the propagation environment, (e) bandwidth, etc. For a wireless transmission system employing an appreciable number of antennas at both the transmitter and receiver and operating in a so-called Rayleigh fading environment even without coding, the bit rate could be very large, e.g., 36 bits per second per Hz with a reasonable Signal to Noise Ratio (SNR) of 18 dB. Heretofore, it was difficult for a communications system to exchange data at a fraction of such a rate. The main reason for this is that the prior art did not appreciate the problems that had to be solved in order to build a large bit rate system.
SUMMARY OF THE INVENTION
We have recognized that a wireless communications system that transmits at a substantial bit rate may be achieved, in accordance with an aspect of the invention, by decomposing an m-dimensional system into m-one dimensional systems (of possibly a different capacity) when the transfer (H matrix) characteristics of the wireless channel are unknown to the transmitter. More specifically and in accordance with the principles of the invention, a burst of signal vectors is formed from different data symbols and then transmitted by a transmitter via a Multi-Element Antenna Array. The transmitted vector symbols are received as signal vectors by a plurality of different antennas associated with a wireless receiver. The symbol components of the transmitted vector symbol have an (arbitrary) order and the receiver determines the best reordering of these transmitted components and then processes the received vector to determine the reordered transmitted symbol components. Such processing starts with the lowest (e.g., first) level of the reordered components, and for each such level, cancels out interfering contributions from lower levels, if any, and nulls out interfering contributions from higher levels, if any.
Such receiver processing includes, in accordance with one embodiment of the invention, compensating the weaker of the received transmitted signal components by first removing the interference from the stronger of the received transmitted components, and then processing the result to form the bit decisions.
These and other aspects of the invention may be appreciated from the following detailed description, accompanying drawings and claims.
REFERENCES:
patent: 4530087 (1985-07-01), Yamamoto
patent: 4710944 (1987-12-01), Nossen
patent: 5151919 (1992-09-01), Dent
patent: 5203018 (1993-04-01), Hirose
patent: 5260968 (1993-11-01), Gardner et al.
patent: 5289499 (1994-02-01), Weerackody
patent: 5442625 (1995-08-01), Gitlin et al.
patent: 5448602 (1995-09-01), Ohmori et al.
patent: 5469465 (1995-11-01), Birchler et al.
patent: 5481570 (1996-01-01), Winters
patent: 5579304 (1996-11-01), Sugimoto et al.
patent: 5787122 (1998-07-01), Suzuki
patent: 5796775 (1998-08-01), Aoyama
patent: 5831977 (1998-11-01), Dent
patent: 5832044 (1998-11-01), Sousa et al.
patent: 5889826 (1999-03-01), Takahashi
patent: 5960039 (1999-09-01), Martin et al.
patent: 6058105 (2000-05-01), Hochwald et al.
patent: 6097771 (2000-08-01), Foschini
patent: 6115427 (2000-09-01), Calderbank et al.
Chiznik, Foschini and Valenzuela “Capacities of Multi-Element Transmit and Receive Antennas: Correlations and Keyholes” Electronics Letters vol. 36 No. 13, Jun. 22, 2000, pp. 1099-1100.*
Gerald J. Foschini “Layered Space-Time Architecture for Wireless Communication in a Fading Environment When Using Multi-Element Antennas” Bell Labs Tech. Jrnl, autumn 1996 pp. 41-59.*
“Throughput Improvement Scheme in Multi-Code CDMA” Kim, I.M.; Shin, B.C.; Kim, Y.J.; Kim, J.K.; Han, I.; Electronics Letters vol. 34 10, May 14, 1998, pp 963-964.*
“A Spread-Spectrum Multiaccess System with Cochannel Interference Cancellation for Multipath Fading Channels” Yoon et al, H. Selected Areas in Comms., IEEE Jrnl on, vol. 11 7, Sep. 1993, pp 1067-1075.*
“CDMA-IC: A Novel Code Division Multiple Access Scheme Based on Interference Cancellation” Dent et al; Personal, Indoor and Mobile Radio Comms., 1992. Proc, PIMRC '92, Third IEEE Int. Symp., 1992, pp 98-102.*
“Combination of an Adaptive Array Antenna and a Canceller of Interference for DS-SS Multiple-Access System” Kohno et al, Selected Areas in Comms., IEEE Jrnl on, vol: 8 4, May 1990 pp 675-682.*
“Interference Rejection in Digital Wireless Communications” Laster, J.D.; Reed, J.H. IEEE Signal Processing Magazine vol.: 14 3, May 1997, pp 37-62.*
“Spatial and Temporal Filtering for Co-Channel Interference in CDMA” Kohno, R. Spread Spectrum Techniques and Applications, 1994. IEEE ISSSTA '94, IEEE Third Int. Symp. on, 1994, pp 51-60 vol. 1.*
A. B. Carleial, “A Case Where Interference Does Not Reduce Capacity”, IEEE Trans. Information Theory, Sep. 1975, pp. 569-570.
M. L. Honig, K. Steiglitz, and B. Gopinath, “Multichannel Signal Processing for Data Communications in the Presence of Crosstalk”, IEEE Trans. Comm., vol. 38, No. 4, Apr. 1990, pp. 551-558.
J. H. Winters, “Signal Acquisition and Tracking with Adaptive Arrays in the Digital Mobile Radio System IS-54 with Flat Fading,” IEEE Trans. on Vehicular Technology, vol. 42, Nov. 1993, pp. 377-384.
R. L. Cupo, G. D. Golden, C. C. Martin, K. L. Sherman, N. R. Sollenberger, J. H. Winters, and P. W. Wolniansky, “A Four-Element Adaptive Antenna Array for IS-136 PCS Base Stations”, Proc. 1997 IEEE 47thVehicular Technology Conference, May 1997, pp. 1577-1581.
J. H. Winters, J. Salz, and R. D. Gitlin, “The Impact of Antenna Diversity on the Capacity of Wireless Communication Systems,” IEEE Trans. on Communications, vol. 42, Feb./Mar./Apr. 1994, pp. 1740-1751.
Foschini Gerard Joseph
Golden Glenn David
Lin Reitseng
Lucent Technologies - Inc.
Luludis F. B.
Rupert Paul N.
Tse Young T.
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