A Method of User Channel Estimation

Abstract

The invention relates to a pilot frequency structure, a pilot frequency transmitting method, and a user channel estimation method. The pilot frequency structure comprises L uplink pilot frequency time slots and one uplink data frame, wherein each uplink pilot frequency time slot is provided with K types of candidate orthogonal pilot frequency sequences. The L uplink pilot frequency time slots are respectively arranged from number 1 to number L, and the uplink data is arranged behind the L uplink pilot frequency time slots, wherein L>1, and K>=1. Compared with a conventional pilot frequency structure which just has one uplink pilot frequency time slot, the pilot frequency structure has L uplink pilot frequency time slots, and can greatly reduce the probability of pilot frequency conflict caused by the random access of users in a cell.

Description

technical field [0001] The invention relates to the field of multi-user large-scale antenna array communication systems, in particular to a pilot structure, a pilot transmission method and a user channel estimation method. Background technique [0002] In a multi-user large-scale antenna array communication system, multiple users transmit pilot sequences and uplink data at the same time, and the uplink transmission time of each user is synchronized with each other. There may be multiple users transmitting pilot sequences in each uplink pilot time slot, but If the pilot sequences sent by each user are sine waves of different frequencies or symbols at different times or mutually orthogonal codes, then the pilot sequences of each user can be orthogonal, and the base station can correctly estimate the frequency of each user. channel to solve the uplink data of each user; but if multiple users choose the same pilot sequence, it is called pilot conflict, and the receiving end of t...

AI Technical Summary

Problems solved by technology

[0002] In a multi-user large-scale antenna array communication system, multiple users transmit pilot sequences and uplink data at the same time, and the uplink transmission time of each user is synchronized with each other. In each uplink pilot time slot, multiple users may transmit pilot sequences, but If the pilot sequences sent by each user are sine waves of different frequencies or symbols at different times or mutually orthogonal codes, then the pilot sequences of each user can be orthogonal, and the base station can correctly estimate the frequency of each user. channel, to solve the uplink data of each user; but if multiple users select the same pilot sequence, it is called pilot conflict, and the base station receiving end cannot obtain the channel estimation and uplink data of the conflicting users, which is solved in the prior art The method of pilot conflict is: the solution in LTE is to increase the number of interactions between the terminal and the base station, and finally the base station selects a certain user from the users who have pilot collision to continue to access

But for MTC scenarios: most of the devices are randomly accessed; the number of terminals is large, and the probability of collision is high; the bandwidth is narrow, and the interaction with the base station is time-consuming

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