Harmonic Characteristics Analysis of Signals After 1-bit Quantization

This paper investigates the factors leading to the limited two-tone instantaneous dynamic range of monobit receivers and explores its possible upper bound. For the purposes, statistical results of the amplitude relationships among odd harmonics, intermodulation product and fundamental components in a two-tone 1-bit sampled signal are collected by simulation. Through analyzing the statistical results, the primary cause for the low two-tone instantaneous dynamic range of traditional monobit receivers (typically only 5 dB) is revealed reasonably for the first time. Then, the study concluded that 1) Accurately identifying or suppressing the third harmonic of the stronger signal can increase the two-tone instantaneous dynamic range of a monobit receiver to 10 dB; 2) If the fifth harmonic of the stronger signal can be also identified or suppressed, the two-tone instantaneous dynamic range can be further increased to 12 dB; 3) When the input power ratio of the two-tone signal exceeds 12 dB, distinguishing the fundamental component of the weaker signal from the three-order intermodulation product based solely on their amplitudes becomes challenging with the current techniques. Therefore, the achievable upper limit for the two-tone instantaneous dynamic range of a monobit receiver is 12 dB. This research provides valuable insights for improving the two-tone instantaneous dynamic range of monobit receivers in practical engineering applications.