Efficient Frequency Offset Estimation Circuit Design for Wi-Fi Receivers
Frequency offset estimation ensures orthogonality between symbols in an orthogonal frequency division multi-plexing system,and it is an important step for signal processing in Wi-Fi receivers.Addressing the trade-off be-tween computational accuracy and resource consumption while designing frequency offset estimation circuits,one such high-efficiency circuit was designed in this study.First,the simulation of the data processing flow of frequency offset estimation was performed to explore the effect of different data-bit widths on the root mean square error of the estimation results.Further,the dynamic range of intermediate variables at each level was divided into fine grains,and appropriate data-bit widths and truncation methods of intermediate variables at each level were determined to save hardware resources while ensuring data accuracy.Second,a complex phase angle calculation unit was used to im-prove the circuit performance using look-up tables and approximation calculations.This method can reduce logic re-source consumption by more than 96.9%and the number of execution cycles by 95%.Finally,coarse and fine fre-quency offset estimation shared hardware resources using the time division multiplexing design.The resource con-sumption of the circuit was further reduced,and data processing speed was increased by optimizing the pipeline structure.The experimental results showed that at a signal-to-noise ratio of 15 dB,the designed circuit reduced the bit error ratio of the Wi-Fi receiver by about 17.94%compared with that of the coarse frequency offset estimation circuit.In addition,the number of look-up tables consumed was reduced by 71.22%,power consumption was reduced by 24.73%,and the number of cycles required for processing was reduced by 22.90%compared with circuits that per-formed coarse and fine frequency offset estimation,respectively.The designed frequency offset estimation circuit ultimately optimized resource consumption and computational accuracy.
万方数据
维普
