Research On CPM And SM Technology For MIMO Communication Systems

Multiple-input multiple-output(MIMO) communication systems is configured with multiple antennas at the transmitter and receiver, it not only can increase the capacity of wireless communication systems without any additional spectrum and transmission power,but also can improve the reliability of the communication system. Then the MIMO communication system is always being a hot topic of research. To further improve the bit error rate(BER) performance of the MIMO communication systems, this paper had a BER performance study on the continuous phase modulation(CPM) MIMO communication system and the spatial modulation(SM) MIMO communication system,respectively.CPM technology has the high spectrum efficiency and the strong anti-interference advantages. This paper applied the CPM technology to the MIMO communication system and designed a CPM-MIMO system. The CPM-MIMO system combined the advantages of the CPM technology and the MIMO technology; it not only can increase the transmission rate of the system, but also can improve the reliability of the system. The simulation results show that the CPM-MIMO systems can obtain nearly 12 dB gain compared with the CPM-SISO systems when the bit error rate is 10-5while in the Rayleigh fading channel and the MIMO communication system configured with two transmitting antennas and two receiving antennas.Minimum Shift Keying(MSK) is a special continuous phase modulation. In order to improve the reliability of the transmitting video data under the high-speed communication system, this paper designed a high-speed image transmission MIMO communication system based on MSK modulation. The simulation results show that the MSK modulation can receive a better BER performance than the M-PSK modulation but incur not too much complexity increase at the detection and the MSK image transmission for the MIMO communication system can obtain a clearer picture.SM technology transmits information not only by conventional signal modulation but also by selecting the spatial position of the antennas. To improve the BER performance ofthe MIMO communication system, this paper applied the convolution code to the spatial modulation system. Then a spatial modulation system with convolutional coding-aided to design the transmitter antenna’s constellation(CSM) was proposed. At the receiver, this paper used the Viterbi algorithm. Finally, this paper had the BER performance simulation experiments on the CSM system, spatial trellis coded modulation(TCSM) system and space-shift keying modulation system with Hamming coding-aided to design the transmitter antenna’s constellation(HSSK), respectively. The simulation results show that the CSM can obtain a better BER performance than TCSM or HSSK under the same circumstances.