| （英） |
In order to reduce power consumption of receivers, we have been studied 1-bit Analog-to-Digital Converter (ADC) reception using the stochastic resonance phenomenon. The 1-bit ADC is a device which outputs ±1 according to the input signals and is impossible to distinguish signal levels. However, when noise with adequate strength is added to the input signal and stochastic processing of over-sampled outputs of 1-bit ADC, even the device can distinguish signal levels. When the proposed reception method is applied to multi-level Pulse Amplitude Modulation (PAM) or Quadrature Amplitude Modulation (QAM), a bias coccurs in the bit error rate (BER) at high signal-to-noise ratio (SNR) region, where errors of amplitude decision are more likely than those of sign decision. To address this issue, we aim to improve the BER performances oby using set-partitioned coded modulation (SPCM), which applies set partitioning to the set of transmitted symbols and then applies Low-Density Parity Check (LDPC) coding to the sets that are easy to erros. As a first step, we compare the BER performances for 4PAM signals, which are the most basic multi-level signals that can be set-partitioned. We apply all possible set-partitioning methods, in 1-bit ADC reception. This will allow us to discuss how to optimize set partitioning when the number of modulation levels increases.
Acknowledgment This work was supported by JSPS KAKENHI Grant Number JP24K00886. |