Antenna effect on biorthogonal pulses using modified hermit polynomials for UWB communications

الملخص EN

Orthogonal and Biorthogonal pulses are important for high data rate wireless communications and multiple access techniques.

It is also an interesting subject for Ultra wideband (UWB) communications, in which very short duration pulses in the order of sub nanoseconds with very low power spectral density (- 41.5 dBm / MHz) are directly radiated to the air.

However, when these pulses are applied to an appropriately designed antenna and propagate in a frequency-selective fading channel, the bit error rate (BER) performance is severely degraded since the orthogonality among these pulses is partially lost.

In this paper we discuss the effect of antenna on BER performance using biorthogonal pulses based on modified Hermit polynomial (MHP) in additive white Gaussian noise (AWGN) channel.

Due to the increasing importance of UWB communication we focus our discussion on very short duration pulses directly applied to the antenna.

However, the reported results according to the proposed approach are not limited to UWB pulses and can be extended to any other carrier-free technology.

Moreover, for simplicity and clarity reasons, we take only the effect of antennas into consideration assuming beam forming is taking place to combat multipath propagation and postpone the influence of frequency-selective fading channel for future work.