Multi-user signal-to-noise ratio blind estimation method in single-carrier interleaved frequency-division multiple access (IFDMA) system

Abstract

The invention discloses a multi-user signal-to-noise ratio blind estimation method in a single-carrier interleaved frequency-division multiple access (IFDMA) system. The method disclosed by the invention comprises the following steps: (1) converting an input signal into a frequency domain signal; (2) converting the frequency domain data into time domain data; (3) sending a modulated signal; (4) receiving a signal containing noise; (5) separating multi-user signal to obtain each user time domain signal; (6) computing average power of the noise; (7) computing the average power of a single-carrier IFDMA symbol; (8) computing the signal-to-noise ratio of the single-carrier IFDMA symbol; and (9) computing the signal-to-noise ration of each sub-frame. The transmission efficiency of the single-carrier IFDMA system is improved through signal-to-noise blind estimation; the signal-to-noise ratio of each sub-frame is directly computed through a large number of user time domain signals; the accuracy of the signal-to-noise estimation, especially the accuracy of the low signal-to-noise ratio estimation, can be improved.

Description

technical field [0001] The invention belongs to the technical field of communication, and further relates to a blind estimation method for multi-user signal-to-noise ratio in a single-carrier interleaving frequency division multiple access system in the technical field of signal processing. The present invention can be used in communication technical fields such as satellite communication, mobile communication, ionospheric scatter communication, tropospheric scatter communication, adopts single-carrier interleaving frequency division multiple access system (SC-IFDMA), and carries out the signal-to-noise ratio of each user in the system method of blind estimation. Background technique [0002] In communication systems, the common indicators that characterize channel transmission quality include: channel delay spread, signal-to-noise ratio, bit error rate, frame error rate, etc. Among them, the bit error rate and the frame error rate are the direct measurement indicators of t...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that when estimating the SNR, certain prior information is required. In order to improve the accuracy of SNR estimation, more pilot data needs to be inserted into the frequency domain signal, which will reduce the The efficiency of data transmission, but too few pilots will lead to a decrease in the accuracy of signal-to-noise ratio estimation, which cannot reflect the quality of the communication link well and affect the performance of the system

The disadvantage of this method is that it is necessary to use the preamble symbols to estimate the signal power and noise power. If the channel changes drastically, the signal-to-noise ratio estimated by the preamble symbols is no longer applicable to the data symbol part, and the sample data of the preamble symbols is limited. lead to inaccurate estimates of low signal-to-noise ratios

Images