Square contour algorithm: a new algorithm for blind equalization and carrier phase recovery

New blind equalization techniques based on improved square contour algorithm

“…2. It has been revealed through simulation results in [11] that for 16-QAM signal constellation, the performance of SCA is better than that of its parent algorithms, i.e., RCA and CMA. Moreover, like RCA and MMA, SCA is capable of recovering and correcting the phase offset due to square modulus, but SCA is outperformed by MMA in terms of convergence speed and constellation eye opening.…”

“…The objective is to achieve an estimate of s(n) using y(n) without using a train- ing signal available at the receiver. To achieve the aforementioned objective, the SCA proposed by Thaiupathump and Kassam [11] combines the benefits of the well known reduced constellation algorithm (RCA) and the constant modulus algorithm (CMA). The generalized SCA cost function is…”

“…The higher values of p enhance the algorithm performance at the cost of increased complexity. The optimum value of p is 2 which yield good performance with reasonable complexity of implementation [11]. The corresponding tap update equation is obtained by differentiating the mean cost function in Eq.…”

“…The constant R SCA is calculated by assuming the perfect equalization, i.e., y(n) = s(n) and by setting the gradient ∇ w J SCA to zero [11]:…”

“…Recently, Thaiupathump and Kassam [11] have proposed square contour algorithm (SCA) which combines the benefits of CMA and RCA. The scheme implicitly updates phase during convergence and is less likely to converge to incorrect solutions like its parent schemes.…”