ブラインド非線形補償による1-bit ADC受信機の性能改善

抄録

To-achieve multi-band technology and MIMO (Multiple-Input and Multiple-Output) technology, technologies are needed to accommodate multiple frequency bands in the radio section to make the equipment more flexible and compact. Particularly, many studies have been conducted to use an 1-bit ADC (Analog to Digital Converter) for miniaturization^(4)-(11). There have been many reports on research using Dithering technology⁽²⁴⁾ and an 1-bit ADCs that apply the phenomenon of stochastic resonance in recent years⁽²⁵⁾, and the similarity between Dithering technology and stochastic resonance has also been reported⁽²³⁾. An 1-bit ADC using the Dithering technique does not require complex circuits like a Delta-Sigma ADC⁽¹⁷⁾, so it can be implemented with a simpler configuration than a Delta-Sigma ADC and can be downsized when implemented in hardware. However, when used as a receiver, nonlinear distortion of the received signal due to the nonlinearity of the 1-bit ADC is a problem.

Therefore, this paper proposes a method of mitigating the effects of nonlinear distortion caused by an 1-bit ADC by using blind nonlinear compensation in a wideband modulated receiver composed of an 1-bit ADC using Dithering technology. Compensation techniques used to compensate for distortion caused by nonlinearities in nonlinear amplifiers are applied^(12)-(16), and the effect of the improvement is evaluated in terms of the EVM (Error Vector Magnitude) of the signal after reception. We report that the proposed method suppresses the characteristic degradation affected by nonlinear distortion caused by an 1-bit ADC, and that EVM can be reduced by computer simulation.