SNR estimation in direct-sequence spread-spectrum multiple-access systems

Statistics that are obtained from the demodulator are used in a direct-sequence spread-spectrum receiver to provide an estimate of the signal-to-noise ratio. We evaluate the applicability to spread-spectrum multiple-access systems of an SNR estimator that was proposed previously for SNR estimation in systems for which the only disturbance is thermal noise. The proposed estimate does not require the use of pilot symbols or additional overhead and it is obtained prior to packet decoding. The estimator does not require knowledge of the phase, amplitude, or timing of the interference signals.