Frame synchronization and channel acquisition in impulse radio

Frame synchronization and channel acquisition are crucial receiver operations in impulse radio (IR), the most common ultra-wide band system found in the literature. When either the frame epoch or the channel impulse response is known at the receiver, the estimation of the other is straightforward. However, in reality, both need to be estimated from the received signal. One of the major causes for the frames to fall out of sync is the drift due to the mismatch in the transmitter and receiver oscillator frequencies. In this paper, we develop a novel (digital) technique to estimate the frequency mismatch and the channel, in which, the estimation problem is decoupled into two separate problems and solved in an iterative fashion. We show that the proposed estimation scheme can achieve the required accuracy for reliable data detection in a coded system, with simple, commercially available oscillators.