Sec. 22.623  System configuration.

    This section requires a minimum configuration for point-to-
multipoint systems using the channels listed in Sec. 22.621.
    (a) 928-960 MHz. The channels may be assigned, individually or 
paired, only to fixed transmitters in a system that controls at least 
four public mobile base transmitters that transmit on the same channel. 
If a 932-933 MHz channel and a 941-942 MHz channel are assigned as a 
pair, the 941-942 MHz channel must be assigned only to control 
transmitters; the 932-933 MHz channel may be assigned to control or 
fixed relay transmitters.
    (b) 470-512 MHz. These channels may be assigned only individually 
(unpaired), to control transmitters that directly control at least four 
public mobile base transmitters that transmit on the same channel. Fixed 
relay transmitters are not authorized.
    (c) Selection and assignment. The FCC selects and assigns a channel 
when granting applications for authorization to operate a new station to 
transmit in the 470-512, 932-933 and 941-942 MHz frequency ranges. 
Applicants having a preference may request the assignment of a specific 
channel or channel pair, but the FCC may in some cases be unable to 
satisfy such requests.