This paper compares two multiuser transmission techniques in the context of wideband upstream powerline communications. The first one is based on the combination of CAP and CDMA, the second one is based on DMT and relies on a share of the different carriers among the users. The issue of reception under ideal synchronisation assumptions and a simplified noise environment is addressed. Fractional FIR linear and decision feedback joint detectors are derived. A heuristic resource (code/tone) allocation algorithm is proposed.