Self-adaptive orthogonal recovery coding method based on signal-to-noise ratio estimation

Abstract

The invention discloses a self-adaptive orthogonal recovery coding method based on signal-to-noise ratio estimation. The method comprises the following steps that 1, a base station end performs initial TDOA value estimation by using a pilot frequency sequence sent by a mobile station; 2, the base station performs phase rotation on elements in the precoding matrix by using the estimated TDOA initial value (shown in the specification), performs phase rotation on the elements in the precoding matrix by using the estimated TDOA initial value; and compensates for channel non-orthogonality caused bythe time delay; 3, the channel estimation and symbol decoding is carried out by a signal decoded by a receiving end; 4, a mobile station estimates the signal-to-noise ratio of the decoded symbol andreports the signal-to-noise ratio to a sending end; 5, the sending end tracks and corrects the TDOA estimation value according to a back-off algorithm to obtain a corrected TDOA delay factor (shown inthe specification); 6, the sending end carries out phase rotation on elements in the precoding matrix according to the TDOA delay factor (shown in the specification) obtained by feedback, and encodesa sent signal. The orthogonal recovery coding of the TDOA estimation value can be adaptively tracked and corrected according to the received signal, and the system performance is improved on the premise of not increasing the system overhead.

Description

technical field [0001] The invention relates to the design of a receiving system in a multi-antenna environment, in particular to an adaptive orthogonal restoration coding method based on signal-to-noise ratio estimation. Background technique [0002] In recent years, with the rapid development of high-speed railway construction, railway transportation is less affected by objective conditions and non-controlling factors, and has gradually become the main means of transportation in various countries. The high-speed operation of the railway greatly facilitates people's travel and greatly shortens the running time of the train. While the continuous improvement of the train speed brings convenience to people, it also puts forward higher and higher requirements for the high-speed railway mobile communication system. Railway mobile communication systems are mainly divided into two categories: the first category is the unified dispatch and command of train and rolling stock operati...

AI Technical Summary

Problems solved by technology

Since the fast time-varying fading channel destroys the orthogonality between subcarriers in the OFDM frame, Inter-Carrier Interference (ICI) and Inter-Symbol Interference (ISI) will occur in the SFBC-OFDM system. ), and due to the influence of inter-symbol interference and inter-wave interference, the received signal cannot be well separated at the receiving end, and the performance of the entire communication system will also be seriously affected

At the same time, due to the non-orthogonality of the channel, the system cannot fully obtain the diversity gain brought by space-frequency coding

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