Planisphere mapping based signal-noise ratio estimation method and apparatus in multi-carrier system

Abstract

The invention provides a signal-to-noise ratio estimation method and device based on constellation map mapping in a multi-carrier system. The method includes: performing QAM mapping according to the data information after channel equalization to obtain the ideal position (QAM_out) of the data information on the constellation diagram; calculating the first function value (YH_QAM) of the corresponding point on the constellation diagram of the data information after channel equalization , and the second function value (HH); the first function takes the channel information (H), the ideal position (QAM_out) and the data information (Y) before channel equalization as factors, and the second function takes the channel information (H) as a factor, The first function and the second function constitute the deviation distance (Dist) of the corresponding point relative to the ideal position; the first function value and the second function value of the corresponding point are accumulated respectively; the accumulated first function value and the second function are used value to calculate the signal-to-noise ratio (SNR).

Description

technical field [0001] The invention belongs to the technical field of digital information transmission, and in particular relates to a signal-to-noise ratio (SNR) estimation method and device based on constellation map mapping in a multi-carrier receiver system. Background technique [0002] In the receiver of the multi-carrier system, it is often necessary to use the received signal to estimate the quality of signal transmission, that is, the signal-to-noise ratio (SNR). Traditional estimation methods are mainly divided into the following two categories: [0003] 1) Estimated by using useless sub-carriers in the multi-carrier spectrum. [0004] In a multi-carrier system such as OFDM, in order to effectively protect the transmission of useful subcarrier information, the transmitting end inserts protection subcarriers on both sides of the useful data spectrum with an amplitude of 0; the receiving end can use these useless subcarriers received Carrier information for SNR es...

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