Filter bank multicarrier with offset quadrature amplitude modulation (FBMC/OQAM) has been heavily studied as an alternative waveform for 5G systems due to higher spectrum efficiency and time-frequency localization. However with the property of real-field orthogonality of FBMC/OQAM systems, channel estimation under the intrinsic imaginary interference has been a fundamental obstacle. In this letter, we show that the existing pilot-based methods are trapped by the paradigm that the reference signal must include an independent prime pilot and rely on an auxiliary pilot to neutralize the interference on the prime pilot. By breaking this paradigm, we present a novel scheme, in which it gives up the independent pilot and derives dual-dependent pilots from the imposed interference. By doing this, the interference between the dual-dependent pilots can be fully utilized so that the efficiency of utilizing pilots can be boosted. Consequentially, the simulation results show that the new scheme outperforms the existing solutions.
['Bin Yu', 'Su Hu', 'Pengfei Sun', 'Shengjun Chai', 'Chen Qian', 'Chengjun Sun']
Channel Estimation Using Dual-Dependent Pilots in FBMC/OQAM Systems