We focus on the design of multiuser receiver structures for Code Division Multiple Access (CDMA) communication systems, in the presence of multipath effects and multiple sensors at the base station receiver. The joint channel estimation and detection approach presented in this paper uses a miximum likelihood approach to estimate an effective spreading code [1] vector of each user. We design our channel estimation algorithm to estimate this vector in a computationally efficient manner, instead of focusing on estimation of the individual channel parameters, such as path delays, attenuation factors, and direction of arrival. We present a framework that allows the use of the estimated effective spreading code in the detection process [2] and facilitates the development of a computationally efficient solution to the combined problem of channel estimation and multi-shot detection in a scenario involving multiple users, multiple paths, and multiple sensors.