A QCQP design method of the symmetric pulse-shaping filters against receiver timing jitter

This paper presents a method for designing linear-phase square-root (SR) FIR digital filters that alleviate the effect of receiver timing uncertainty by the quadratically constrained quadratic programming. As in the previous work, we take the “roughness” of the hybrid analog/FIR-SR filter impulse response as the cost function and the filter's stopband attenuation and the system's tolerable ISI as constraints. However, instead of using the time-domain formulation in the previous work, we formulate the cost function and the constraints in the frequency domain, which turns the design problem into a quadratic one. Solving the design problem by the time-domain formulation requires a good initial guess while solving the problem by the new formulation does not. Experiments on a software defined radio platform show that the designed filter by the proposed method outperforms the prior art even though the perfect clock recovery subsystem is not realized on a modern low-cost electronic communication system.