Performance Analysis of Large Scale Antenna System With Carrier Frequency Offset, Quasi-Static Mismatch and Channel Estimation Error

Relaying Systems With Reciprocity Mismatch: Impact Analysis and Calibration

“…5 shows that the achievable rate decreases with the number K of S-D pairs increasing. This is because the power allocated to each user decreasing with the increasing of K, while the multiplexing gain of the cooperative relaying system increases, which can be analytically concluded from (11). Moreover, the figure also demonstrates that the achievable rate increases slowly with the increase of antennas, which implies that the system where relays are equipped with more antennas is more robust to the reciprocity mismatch.…”

“…which is a benchmark of ergodic achievable rate of the relaying system with ZF beamforming. Although the achievable rates are derived in (11) and (14), it is difficult to get significant insights from these expressions directly. Hence, further impact analysis of the reciprocity mismatch on the relaying system performance is discussed in the next section.…”

“…But ZF is also more sensitive to the reciprocity mismatch than MF, especially in the high signal-to-noise ratio (SNR) regime [10]. In massive MIMO, ZF and MF almost achieve the same performance in asymptotic comparisons [11]. It is noticed that the impact of the mismatch at user equipment (UE) side is much smaller than that at BS side [12].…”

Impact and Calibration of Nonlinear Reciprocity Mismatch in Massive MIMO Systems

“…In practice, the channel observed by the baseband processor consists of not only the reciprocal wireless propagation channel, but also the radio frequency (RF) gains resulting from the frequency responses of hardware devices, i.e., high power amplifier (HPA), filters, analog-to-digital converter (ADC), and digital-to-analog converter (DAC) [5]. Due to the involvement of different devices, the overall gains of the RF chains at BS and UEs are typically asymmetric, which leads to the reciprocity mismatch of the uplink and downlink channels [6].…”

Frequency Synchronization for OFDM-Based Massive MIMO Systems

“…All the above advantages of massive MIMO systems rely on accurate synchronization. However, massive MIMO systems heavily suffer from synchronization errors, such as, timing offset (TO) and carrier frequency offset (CFO), [9], [10], [11].…”