On co-channel interference measurements

The spectral efficiency of a cellular mobile radio system is enhanced through the reuse of the available spectrum. The resulting co-channel interference, however, also limits the system capacity. Power control is needed so that co-channel interference can be maintained within a tolerable bound. Therefore, co-channel carrier to interference ratio (CIR) is often used as a quality indicator for received signals. Various power control algorithms assume perfect CIR measurement have been proposed but there is no mentioning of the measurement method. This paper presents viable solutions for real-time CIR estimations under either additive white Gaussian noise (AWGN) or Rayleigh fading condition. A new algorithm that uses the concept of probability density function matching is also proposed to measure CIR in the presence of multiple interferers. Numerical results are provided to demonstrate the usefulness of the proposed algorithms