Sampling jitter cancellation in direct-sampling radio

Abstract

This paper addresses the sampling jitter estimation and cancellation task in direct RF sub-sampling type radios. The proposed jitter estimation method is based on carefully injecting or superimposing an additional known reference signal to the received signal at the sampler input. Proper digital signal processing methods are then devised and applied to estimate the sampling jitter realizations from the obtained jittered samples. Using these jitter estimates, combined with proper jitter modelling, the jitter effects can then be efficiently removed from the actual received signal. Careful performance analysis of the overall estimation-cancellation scheme is also carried out using computer simulations with 3GPP LTE type multicarrier signals, assuming also different amounts of RF filtering prior to RF sub-sampling stage. In the performance simulations, both additive white Gaussian noise and extended ITU-R Vehicular A multipath radio channel types are considered.