Effects of Spreading and Training on Capacity in Overloaded CDMA

We address the issue of sum-capacity in an overloaded, uplink, synchronous CDMA system in a quasi-static fading environment. Part of each fading block is reserved for channel training and the remainder of the block is used for data transmission. We evaluate bounds on sum-capacity using the estimates from channel estimation, and consider the effects on the lower bound caused by the spreading-coding-training tradeoff.