  This paper firstly introduces our shared Matlab source code that simulates
the two optimal-ordered SIC detectors proposed in [1] and [2]. Based on our
shared Matlab code, we compare the computational complexities between the two
detectors in [1] and [2] by theoretical complexity calculations and numerical
experiments. We carry out theoretical complexity calculations to obtain the
worst-case complexities for the two detectors in [1] and [2]. Then from the
theoretical worst-case complexities, we make the conclusion that the detector
proposed in [2] requires 9N 2 more floating-point operations (flops) than the
detector proposed in [1], where N is the number of transmit antennas. Our
numerical experiments also show that the detector in [2] requires more
worst-case and average complexities than the detector in [1].
