Based on the frequency-domain analog-to-digital conversion (FD ADC), this work builds a low-complexity sequential searcher for robust symbol synchronization in a 4$,times,$ 4 FD multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) modem.
The proposed scheme adopts a symbol-rate sequential search with simple cross-correlation metric to recover symbol timing over the frequency domain. Simulation results show that the detection error is less than 2% at signal-to-noise ratio (SNR) $leqq $5 dB.
Performance loss is not significant when carrier frequency offset (CFO) $leqq $100 ppm.
Using an in-house 65-nm CMOS technology, the proposed solution occupies 84.881 k gates and consumes 5.2 mW at 1.0 V supply voltage. This work makes the FD ADC more attractive to be adopted in high throughput OFDM systems
Simulation: ModelSim XE III 6.4b.
Synthesis: XiLinx ISE 10.1.