Journal ArticleDOI
An implementation of a CMA adaptive array for high speed GMSK transmission in mobile communications
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TLDR
The hardware implementation of an adaptive array as a technique for compensating multipath fading in mobile communications is described, and the result of the basic field test shows that the gain at a BER of 1.0*10/sup -3/ reaches 22.3 dB in a nonselective, slow Rayleigh fading channel given a 5 Hz maximum Doppler shift.Abstract:
The hardware implementation of an adaptive array as a technique for compensating multipath fading in mobile communications is described. The number of the antenna elements is four. The target communication system is modulated by 256 kbps Gaussian-filtered minimum shift keying (MSK) and has a time-division multiplexing (TDM) architecture with 24 time slots. Based on the digital beamforming concept, all of the signals and the array weights are digital-signal processed. The constant modulus algorithm (CMA) is employed for weight optimizing. In an additive white Gaussian noise channel, this system has 5.6-dB gain in an energy-per-bit-to-noise-density ratio at a bit error rate (BER) of 1.0*10/sup -3/, compared with a single antenna system. The result of the basic field test shows that the gain at a BER of 1.0*10/sup -3/ reaches 22.3 dB in a nonselective, slow Rayleigh fading channel given a 5 Hz maximum Doppler shift. >read more
Citations
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Journal ArticleDOI
Application of antenna arrays to mobile communications. II. Beam-forming and direction-of-arrival considerations
TL;DR: This paper provides a comprehensive and detailed treatment of different beam-forming schemes, adaptive algorithms to adjust the required weighting on antennas, direction-of-arrival estimation methods-including their performance comparison-and effects of errors on the performance of an array system, as well as schemes to alleviate them.
Journal ArticleDOI
Applications of antenna arrays to mobile communications. I. Performance improvement, feasibility, and system considerations
TL;DR: This paper presents an overview of mobile communications as well as details of how an array may be used in various mobile communications systems, including land-mobile, indoor-radio, and satellite-based systems.
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Journal ArticleDOI
A novel adaptive beamforming algorithm for a smart antenna system in a CDMA mobile communication environment
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TL;DR: The proposed beamforming algorithm is applied to the base station of a code-division-multiple access (CDMA) mobile communication system and the performance is shown in multipath fading communication channels in terms of the signal-to-interference+noise ratio, the bit error rate, and the achievable capacity of a given CDMA cell/sector.
References
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TL;DR: In this article, an adaptive digital filtering algorithm that can compensate for both frequency-selective multipath and interference on constant envelope modulated signals is presented, which exploits the fact that multipath reception and various interference sources generate incidental amplitude modulation on the received signal.
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GMSK Modulation for Digital Mobile Radio Telephony
K. Murota,K. Hirade +1 more
TL;DR: In this article, a digital modulation for future mobile radio telephone services is proposed, and its fundamental properties are clarified with the aid of machine computation, and the constitution of modulator and demodulator is discussed from the viewpoints of mobile radio applications.
Journal ArticleDOI
Optimum combining in digital mobile radio with cochannel interference
TL;DR: In this paper, the authors used analytical and computer simulation techniques to determine the performance of optimum combining when the received desired and interfering signals are subject to Rayleigh fading, and they showed that optimum combining is significantly better than maximal ratio combining even when the number of interferers is greater than number of antennas.