A Hardware Method for Real-time Snr Estimation for M-psk Using a Symbol Synchronization Lock Metric

In this paper we present and analyze a method for channel SNR (Signal to Noise Ratio) estimation for M-PSK, which is based upon the exploitation of the statistics of a symbol synchronization lock metric. The analysis pertains to AWGN (Additive White Gaussian Noise) channels in systems whose baseband pulse shape is Square-Root Raised Cosine (SRRC) or rectangular. It is shown that, in terms of latency, the proposed SNR estimation method often offers an improvement of several orders of magnitude as compared to estimation via the SER (Symbol Error Rate) or the BER (Bit Error Rate). The proposed method is also very simple to implement in hardware and is resistant to fading and to imperfections in the operations of the AGC (Automatic Gain Control) circuit.