Wavelet Packet based Multi-Carrier Modulation (WPMCM) offers an alternative to the well-established OFDM as an efficient multicarrier modulation technique. It has the advantage of being a generic transmission scheme whose actual characteristics can be widely customized to fulfill several requirements and constraints of advanced communication systems. In the last decades wavelets have been favorably applied in signal and image processing fields but only recently have they attracted the attention of the telecommunication community. A lot of research questions remain to be addressed before the novel WPMCM can be used in practice. One of the major concerns is the performance of WPMCM transceivers under time synchronization errors. This is important because WPMCM symbols overlap in the time domain. In this paper, we analyze the interference in WPMCM transmission caused by the time synchronization errors. The expressions for Inter Carrier Interference (ICI) and Inter Symbol Interference (ISI) in WPMCM transmission are derived and then through simulation studies, the ability of wavelet-based systems to cope with time synchronization errors is evaluated.

Abstract-Wavelet Packet based Multi-Carrier Modulation (WPMCM) offers an alternative to the well-established OFDM as an efficient multicarrier modulation technique. It has strong advantage of being a generic transmission scheme whose actual characteristics can be widely customized to fulfill several requirements and constraints of an advanced communication systems. However, a few research questions remain to be addressed before the novel WPMCM can be used in practice. One of the major concerns is the performance of WPMCM transceivers in the presence of analogue radio frequency front-end imperfections. In this paper we analyze the impact of interference in WPMCM transmission caused by the carrier frequency offset and phase noise. The sensitivity of WPMCM transceivers to these errors using standard wavelets is evaluated through simulation studies and their performances are compared and contrasted with OFDM.

Wavelet Packet based Multi-Carrier Modulation (WPMCM) is an efficient transmission technique which has the advantage of being a generic scheme whose characteristics can be customized to fulfill a design specification. However, WPMCM is sensitive and vulnerable to time synchronization errors because its symbols overlap. In this paper, we design new wavelets to alleviate WPMCM's vulnerability to timing errors. First, a filter design framework that facilitates the development of new wavelet bases is built. Then the expressions for errors due to time offset in WPMCM transmission are derived and stated as a convex optimization problem. Finally, an optimal filter that best handles these deleterious effects is designed by means of Semi Definite Programming (SDP). Through computer simulations the performance advantages of the newly designed filter over standard wavelet filters are proven.

No abstract

No abstract