• ETRI Journal
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• v.38 no.6
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• pp.1042-1051
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• 2016

The mobile hotspot network (MHN), which is capable of providing a data rate of gigabits per second at high speed, is considered a potential use case of the future enhanced mobile broadband for 5G. Because a unidirectional network deployment has been considered for an MHN, non-orthogonal multiple access (NOMA) can be employed to improve the system performance. For a practical implementation of NOMA under an MHN highway scenario where multiple pieces of MHN terminal equipment are served through the same beam simultaneously, a NOMA transceiver is proposed in this paper. For the NOMA transmitter, Gray-coded QAM constellation mapping is extended to arbitrary modulation order q. For the NOMA receiver, successive interference cancellation (SIC) is no longer necessary, and instead, a parallel demodulation is proposed. The numerical and simulation results suggest that the proposed NOMA transceiver outperforms the conventional NOMA SIC receiver and can be flexibly used for an MHN highway scenario.

• Journal of Communications and Networks
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• v.9 no.1
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• pp.11-17
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• 2007

In this paper, system performance of turbo trellis coded modulation (turbo TCM) is presented and analyzed through computer simulations over two typical channels, namely additive white Gaussian noise (AWGN) and Rayleigh fading channels. We use and compare different mapping strategies based on Ungerboeck partitioning (UP), block partitioning (BP), mixed partitioning (MP), Gray partitioning (GP), and Ungerboeck-Gray partitioning (UGP) of the signal constellation of the turbo TCM system. Furthermore, taking 8PSK modulation of turbo TCM as an example, our simulation results show that turbo TCM with UP can obtain better performance than turbo TCM with BP, MP, GP, and UGP in both AWGN and Rayleigh fading channels.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.5
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• pp.71-76
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• 2000

A TC-16ADPSK scheme for transmitting different kinds of information simultaneously is proposed in this paper. The scheme is designed for simultaneously transmitting two kinds of Information on one channel. In signal mapping, a data of two kinds of information is used to phase modulation on Star-16APSK constellation and the other to amplitude modulation. In detection, each data independently recovers from mixing signal on each detector Therefore, we can transmit two kinds of Information on one channel can be transmitted efficiently. BER performance of the proposed scheme is analyzed on AWGN channel and Rayleigh fading channels on a computer with Matlab communication toolbox. On same SNR, the Gray code mapping has more 0.5-1.5dB coding gains than Ungerboeck's code mapping gains.