Short burst MIMO-OFDM communication system and method based on differential coding

Abstract

The invention belongs to the technical field of wireless mobile communication, and discloses a Short burst MIMO-OFDM communication system and method based on differential coding. The method includes:inputting a short burst data stream to be sent; performing channel coding; carrying out constellation mapping; based on a differential coding mode, adopting a method for carrying out difference on OFDM subcarriers; carrying out OFDM modulation; after the receiving end receives the signal, carrying out OFDM demodulation, removing a cyclic prefix, and then carrying out fast Fourier transform (FFT);performing differential space-time frequency decoding; performing constellation inverse mapping; performing channel decoding; and obtaining the output required data. According to the method, the problem caused by channel estimation is solved, pilot frequency does not need to be added into a frame structure, and the utilization rate of data symbols in a short frame structure is improved; the adopted differential space-time-frequency coding method can reduce redundant data under short burst and can obtain the maximum diversity; and channel coding is further added, so that the system reliabilitycan be further improved.

Description

technical field [0001] The invention belongs to the technical field of wireless mobile communication, and in particular relates to a short burst MIMO-OFDM communication system and method based on differential coding. Background technique [0002] At present, the existing technology in the industry is as follows: short burst communication systems are often used in military communications, satellite communications, and deep space communications. In order to ensure the confidentiality of transmitted information, the system usually uses short frame structure and burst transmission Way. The characteristics of the short burst communication system will bring more difficulties to the channel estimation. According to whether the pilot is added to the transmitted frame sequence, the channel estimation can be divided into the auxiliary information channel estimation algorithm and the blind channel estimation algorithm. Although the blind estimation algorithm There is no need to send a...

AI Technical Summary

Problems solved by technology

For the multi-antenna transmission environment in the wireless network, many scholars have also conducted research on the encoding of multiple antennas in the case of unknown channel state information at the transmitter and receiver, but the technical complexity of the existing schemes is relatively high. Subsequently, Tarokh and Jafarkhani constructed a multi-antenna differential space-time codec scheme based on generalized orthogonal design based on the already implemented differential space-time coding scheme for two antennas as an extension of the differential code for two transmitting antennas , which solves the difficult problem caused by channel estimation in multi-antenna transmission, so the present invention applies differential coding technology to short-burst communication systems, and solves the impact of channel estimation on short-burst communication systems

[0004] To sum up, the problems existing in the prior art are: the channel environment of the existing short-burst communication system is harsh, in the case of a large-scale fluctuation of the signal-to-noise ratio, the length of the training sequence is limited and the environmental factors are more severe. In complex situations, channel estimation will be more difficult and the accuracy of received data will be lower

[0005] Difficulty in solving the above technical problems: Existing technologies are constantly improving channel estimation to increase performance accuracy, but for short burst communication systems, pilot or training sequence overhead is required, which will occupy a certain amount of data resources, and the computational complexity is also large

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