RF impairments in high-rate wireless systems - understanding the impact of TX/RX-asymmetry

Abstract

Abstract-Dealing with radio frequency (RF) front-end impairments will be one of the major design challenges for nextgeneration wireless communication systems due to conflicting requirements, such as high data rate, low cost and low power consumption. The use of digital compensation of the imperfections appears a very promising method to meet specifications. Pursuing that path, however, requires thorough understanding of the influence of the RF front-end non-idealities on the received signal and the resulting system performance.To this end, this paper reviews the impact of three important impairments, namely, phase noise, IQ imbalance and nonlinearities, on the performance of next-generation high-rate wireless systems. A specific focus is on the difference between transmitter (TX) and receiver (RX) incurred imperfections. Moreover, a generalized error model to capture to aggregate influence of different impairments is presented.

An Investigation of Using Loop-Back Mechanism for Channel Reciprocity Enhancement in Secret Key Generation

“…Precoding techniques are proposed to compensate the transceiver non-reciprocity with a priori knowledge [35]. The compensation and calibration techniques at transmitter side was widely studied in wireless TDD communication systems [12], [13], [35]. A channel gain complement mechanism was designed to assist the secret key extraction with the help of subcarrier amplitude information in [36], which can achieve a speed of 90 bits per packet with 3-bit quantization.…”

“…The relative movements between users will cause CSI variations in half-duplex measurements [9], [10]. • Hardware fingerprint interference: Due to the manufacturing deviation of radio components, the features of the hardware are inherently different at each device, including non-linearity of power amplifier, transceiver filter characteristic, receiver auto gain control (AGC) response and antenna coupling mismatch [11], [12], [13]. • System synchronization errors: The oscillators at transmitter and receiver deviate in terms of frequency and phase, which will result in synchronization errors, and consequently yield CSI non-reciprocity.…”

5G – Wireless Communications for 2020

“…Besides the previous discussion, some other challenges for implementation of potential 5G techniques can be cited [100,104,108]:…”

Analytical modeling for EVM in OFDM transmitters including the effects of IIP3, I/Q imbalance, noise, AM/AM and AM/PM distortion

“…Most of the research work on analysis of non-linearity effect in OFDM systems are based on statistical approximation [10], [11]. They assume infinite number of sub-carriers.…”

“…Gain and phase imbalance is modeled in the receiver side. Similarly, complex Gaussian assumption for OFDM signal is used in [10] to use the result of Bussgang theorem. Thus, the effect of non-linearity on the OFDM baseband signal is modeled as a scaled version of the signal plus statistically independent distortion process.…”