BER sensitivity to mistiming in ultra-wideband impulse Radios-part I: nonrandom channels

We investigate timing tolerances of ultra wideband (UWB) impulse radios. We quantify the bit-error-rate (BER) sensitivity to epoch timing offset under different operating conditions, including frequency flat fading channels, dense multipath fading channels, multiple access with time hopping, and various receiver types including sliding correlators and RAKE combiners. Our systematic approach to BER derivations under mistiming can be extended to a wide range of channel fading types. Through analyses and simulations, we illustrate that the reception quality of a UWB impulse radio is highly sensitive to both timing acquisition and tracking errors. In particular, time-hopping-based multiple-access systems exhibit little tolerance to acquisition errors, and the energy capture capability of a RAKE combiner can be severely compromised by mistiming.