Abstract
This paper proposes a scalar ambiguity estimation method that sublimates the blind channel estimation method to totally blind estimation. Generally, the blind channel estimation method can identify the channel impulse response or channel frequency response up to scalar ambiguity. For coherent detection, the ambiguity should also be estimated. Exploiting the multiple modulation scheme, we estimate the scalar ambiguity for zero forcing equalization by maximum likelihood (ML). We also detect some equalized symbols fed into the ML estimation, which reduces the computational complexity of the proposed scalar ambiguity estimation. To efficiently reduce the complexity, we derive the Bayesian Cramér Rao lower bound (BCRB) of the ambiguity estimation. When evaluated in computational simulations, the performance of the proposed method achieved the BCRB performance at high signal-to-noise ratios. We also confirmed that when the proposed method is combined with the existing blind channel estimation, coherent detection is possible without any pilot symbols.
Original language | English |
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Article number | 9295375 |
Pages (from-to) | 2608-2620 |
Number of pages | 13 |
Journal | IEEE Transactions on Wireless Communications |
Volume | 20 |
Issue number | 4 |
DOIs | |
Publication status | Published - 2021 Apr |
Externally published | Yes |
Keywords
- Bayesian Cramér Rao lower bound
- Blind channel estimation
- OFDM
- scalar ambiguity
- totally blind channel estimation
ASJC Scopus subject areas
- Computer Science Applications
- Electrical and Electronic Engineering
- Applied Mathematics