A wireless communication base station assembly includes at least one base band unit (40) having one primary circuit board (100) with circuitry for a control function (102), a timing function (104), a line interface function (106) and a radio interface function (108). The electronics and circuitry for each of these functions are all supported on the one primary circuit board (100). At least one channel module (e.g., a channel card) is coupled to the primary circuit board. A single, generally rectangular housing (42) contains the primary circuit board and the channel module. Disclosed examples include a rack (50) having a plurality of slots (52) configured to accommodate the housing (42).