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Analyzes the performance of truncated power control in a code-division multiple-access communication system. Correlation between the CDMA and receivers; Direct sequence CDMA system with binary phase shift-keyed (BPSK) signaling; Outage probability and power gain of truncated power control applied to single-cell systems and multiple cell systems.

Investigates the theoretical limits of spectral efficiency cellular data systems where mobile users continuously adapt their rate relative to the area spectral efficiency (ASE). Description of the channel and system models; Concept of the ASE; Analysis of the ASE when only path loss in considered; Impact of shadowing and multipath fading on the ASE.

Studies the Shannon capacity transmission techniques in conjunction with diversity combining of Rayleigh fading channels. Description of the channel and communication system model; Optimal simultaneous power and rate adaptation of data transmission; Channel inversion with fixed rate; Comparison with additive white Gaussian noise (AWGN) channel; Optimal rate adaptation with constant transmit power.

Describes the Shannon capacity region for downlink (broadcast) channels with additive white Gaussian noise (AWGN). Requirements of wireless communication systems; Approach to determining the capacity of a cellular system; Definition of channel capacity; Details on the study.

In this paper, a new technique for simultaneous voice and multiclass data transmission over fading channels using adaptive hierarchical modulation is proposed. According to the link quality, the proposed scheme changes the constellation size as well as the priority parameters of the hierarchical signal constellations and assigns available subchannels (i.e., different bit positions) to different kinds of bits. Specifically, for very bad channel conditions, it only transmits voice with binary phase-shift keying (BPSK). As the channel condition improves, a variable-rate adaptive hierarchical M-ary quadrature amplitude modulation (M-QAM) is used to increase the data throughput. The voice bits are always transmitted in the lowest priority subchannel (i.e., the least significant bit (LSB) position) of the quadrature (Q) channel of the hierarchical M-QAM. The remaining (log2 M - 1) sub-channels, called data subchannels, are assigned to two different classes of data according to the selected priority parameters. Closed-form expressions as well as numerical results for outage probability, achievable spectral efficiency, and average bit error rate (BER) for voice and data transmission over Nakagami-m fading channels are presented. The adaptive techniques employing hybrid binary shift keying (BPSK)/M-ary AM (M-AM) and uniform M-QAM for simultaneous voice and two different classes of data transmission are also extended. Compared to the extended schemes, the new proposed scheme is spectrally more efficient for data transmission, while keeping the same outage probability for voice and data (both classes) as the scheme employing BPSK/M-AM. The new scheme also provides, as a by-product, a spectrally efficient way of transmitting voice and a single-class data. [ABSTRACT FROM AUTHOR]