tds‑ofdm channel estimation and equalization method and system

Abstract

The invention provides a TDS-OFDM (Time Domain Synchronous-Orthogonal Frequency Division Multiplexing) channel estimation equalization method. The TDS-OFDM channel estimation equalization method comprises receiving and storing information frames and extracting a frame header and the data portion of the current information frame and a frame header of the next information frame; processing the data portion of the current information frame so as to obtain data time domain signals, wherein the trailing interference of the frame header of the current information frame in the data time domain signals is eliminated; performing estimation on a channel which is corresponding to the data portion of the current information frame so as to obtain the frequency domain response of the channel; performing the frequency domain equalization on the time domain signals through the frequency domain response so as to obtain a data symbol sequence. The TDS-OFDM channel estimation equalization method can be applied to the large doppler range and a rapid time-varying channel and is suitable for ultra-high-speed mobile application scenarios. The invention also provides a TDS-OFDM channel estimation equalization system.

Description

technical field [0001] The invention belongs to the technical field of digital information transmission, in particular to a TDS-OFDM channel estimation and equalization method and system. Background technique [0002] The terrestrial wireless TV broadcast transmission channel itself has various multipath and fading phenomena. Considering the mobile receiver, it will introduce a large Doppler effect, so the terrestrial wireless TV broadcast transmission channel is a time-varying frequency selection fading channel. [0003] The ultra-high-speed mobile application scenario can correspond to the low-altitude navigation wireless channel, that is, the Doppler Rice channel model with a line-of-sight path (LOS) main path, and the discrete expression of its impulse response is: [0004] [0005] where T S is the sampling period, τ=iT S is the time delay, t=kT S . Rice factor (K=a 2 / c 2 )∈[2,20]dB. [0006] Multipath phase θ n Obey [0,2π) uniform distribution, multipath D...

AI Technical Summary

Problems solved by technology

However, the subcarrier self-cancellation method needs to use part of the subcarriers originally used to transmit data information for encoding, which reduces the frequency band utilization, and its applicable Doppler range cannot reach the kHz level required by the application

However, the general information-assisted anti-Doppler method can better eliminate the Doppler offset of the LOS main path when the radial relative moving velocity of the transceiver is accurately measured, but the velocity measurement value obtained by the actual system has errors, and in the In addition to the LOS main path, there is also multipath interference in the scenario required by the application

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