Massive MIMO;
Indexes;
Estimation;
Power control;
Numerical models;
Fading channels;
Decoding;
Random access scheme;
pilot collision;
pilot allocation;
massive MIMO systems;
PROTOCOL;
D O I:
10.1109/TVT.2021.3111627
中图分类号:
TM [电工技术];
TN [电子技术、通信技术];
学科分类号:
0808 ;
0809 ;
摘要:
We propose a novel grant-based pilot access scheme to tackle the pilot collision in crowded massive multiple-input multiple-output (MIMO) systems. The proposed scheme divides the cell into several annuluses. Then, weaker user equipments (UEs) in each annulus, judged by a decision rule in a strongest-user collision resolution (SUCRe) scheme, send their reselected or allocated idle pilots to a base station (BS). We call this scheme enhanced SUCRe combined idle pilots access (E-SUCR-IPA). We analyze the number of successful UEs and the successful access probability of one UE with respect to its distance to the BS for the E-SUCR-IPA scheme. Numerical results show that the E-SUCR-IPA scheme significantly increases the number of successful UEs while ensuring fairness among UEs compared to baselines.