Exploiting Multiple RISs and Direct Link for Performance Enhancement of Wireless Systems With Hardware Impairments

Symbol error probability of mmWave communications with transmit antenna selection and RISs under the impacts of hardware impairments

“…13 Meanwhile, hardware impairments (HIs) often exist in the transceiver of wireless communications. 28,29 Generally, the sources of HIs include phase noise, in-phase/ quadrature imbalance, and nonlinearities of electronic components such as converters (analog/digital-to-digital/analog), amplifiers (low-noise amplifier in the receiver and high power amplifier in the transmitter), and mixers. [28][29][30][31][32][33][34] Moreover, HIs can lead to imperfect channel state information.…”

“…28,29 Generally, the sources of HIs include phase noise, in-phase/ quadrature imbalance, and nonlinearities of electronic components such as converters (analog/digital-to-digital/analog), amplifiers (low-noise amplifier in the receiver and high power amplifier in the transmitter), and mixers. [28][29][30][31][32][33][34] Moreover, HIs can lead to imperfect channel state information. 31,32,34 Although many HI mitigating schemes have been proposed and applied at the transceivers, the HIs cannot be completely removed because of the intrinsic properties of electronic components and devices such as the phase noise and nonlinearities of low-cost oscillators, converters, mixers, and amplifiers.…”

“…31,32,34 Although many HI mitigating schemes have been proposed and applied at the transceivers, the HIs cannot be completely removed because of the intrinsic properties of electronic components and devices such as the phase noise and nonlinearities of low-cost oscillators, converters, mixers, and amplifiers. [28][29][30][35][36][37] In addition, the HIs may be induced by imperfect estimations of random and time varying hardware characteristics as well as the inaccuracies coming from unsophisticated compensation algorithms and limited precision models. 35 In recent works, the HIs were considered in RIS-assisted wireless communications.…”

“…35 In recent works, the HIs were considered in RIS-assisted wireless communications. 28,29,38 Specifically, the performance of RIS-assisted wireless communications was saturated when the transmit power is high enough due to the effects of HIs. As a result, ignoring HIs when determining the performance of wireless communications can result in some inappropriate conclusions.…”

“…[38][39][40] Although a practical scenario where HIs exist in the RIS-assisted wireless communications was determined, however, either only one transmit antenna or multi-antenna without TAS at the base station was assumed. 28,41,42 In the case of multi-antenna, the system performance was investigated via experiment measurements instead of mathematical derivations. 41 Meanwhile, the case of only one antenna at the base station may be impractical because the base station is often equipped with multiple transmit antennas.…”