1. A method, comprising: operating a receiver to receive a signal over a channel; processing the received signal by executing a two-dimensional (2-D) M survivor multi-resolution search from one search stage to a next search stage by increasing parameter resolution while fixing a number of search operations at each search stage by a predetermined number of parameter survivors, where M is an integer; and determining one of a Maximum Likelihood joint metric or a sub-optimum Maximum Likelihood joint metric based on an accumulated value of survived search stages.