Fast Algorithms for TVAR and MTIE Computation in Characterization of Network Synchronization Performance

Time Variance (TVAR) and Maximum Time Interval Error (MTIE) are historically the main time-domain quantities for the specification of network synchronization performance in telecommunications standards. Nevertheless, plain computation of the TVAR and MTIE standard estimators proves cumbersome in most cases of practical interest, due to their heavy computational weight. In this paper, TVAR and MTIE are first introduced according to their standard definitions. Then, fast algorithms based on recursion and on binary decomposition to compute the TVAR and MTIE standard estimators are provided, which effectively cut down the number of operations needed. The MTIE algorithm based on binary decomposition reduces the number of operations needed to a term proportional to Nlog N instead of N . Both algorithms allow fast evaluation in most practical situations: even very long sequences of TE samples do not require more than few seconds of data processing for TVAR and MTIE computation

Improving GFDM Symbol Error Rate Performance using Better than Nyquist Pulse Shaping Filters

Fourth generation (4G) cellular systems have been optimized to provide high data rates and reliable coverage to mobile users. New waveforms at the physical layer are needed. Generalized frequency division multiplexing (GFDM) is a candidate modulation for the fifth generation (5G) standard based on multi-branch multicarrier filter bank approach. A main characteristic of GFDM is its low out of band emission, achieved by means of a flexible time-domain pulse shaping of individual subcarriers. In this paper, the influence of the improved Better than Nyquist pulse shaping filters on symbol error rate (SER) performance of the GFDM system in the case of zero forcing (ZF) receiver is investigated. We considered their use in GFDM to evaluate the impact on SER performance in case of 16-QAM transmission over an additive white Gaussian noise channel. Moreover, we also considered the concept of the wavelet for better time-frequency localization of the pulse shaping filters by using the Meyer auxiliary function. Numerical results are reported to demonstrate the superior SER performance achieved