高斯信道下针对LoRa调制的信噪比估计改进算法

信噪比是LoRa自适应网络中实现发射参数准确自适应调节的重要标准,为了增加LoRa调制下信噪比估计的准确性和稳定性,在基于谱分析的信噪比估计算法的基础上,根据LoRa调制解调的特点,提出了一种针对LoRa调制的信噪比估计改进算法。在高斯信道下,利用LoRa解调频谱峰值代表接收信号、其他谱线与噪声具有相关性的特点,定义了信噪比估计参数r,并通过实验确定了不同SF值时信噪比估计参数r与信噪比之间的经验公式,从而准确估计信噪比。仿真结果表明,在最好的情况下改进算法能够准确估计的信噪比提高了-5 dB,以2 dB为标准改进算法的均方根误差能够达到时的信噪比提升了-14 dB,因此与基于谱分析的信噪比估计算法相比,改进算法具有更高的准确性和稳定性。

Improved signal-to-noise ratio estimation algorithm for LoRa modulation over Gaussian channel

Signal-to-noise ratio is an important standard to realize adaptive adjustment of parameters in adaptive configuration of LoRa networks. In order to increase the accuracy and stability of SNR estimation for LoRa modulation, an improved SNR estimation algorithm for LoRa modulation is proposed in this paper. On the basis of the SNR estimation algorithm based on spectral analysis and the characteristics of LoRa modulation, the SNR estimation parameter r is defined, and the empirical formula between r and SNR at different SF is determined through experiments, so as to accurately estimate the SNR. The simulation results show that in the best case the SNR that can be accurately estimated by the improved algorithm is improved by-5 dB, and when the root-mean-square error of the improved algorithm can reach 2 dB the SNR is improved by-14 dB. Therefore, compared with the SNR estimation algorithm based on spectral analysis, the improved algorithm has higher accuracy and stability.