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Technical Developments Volume 7 October 1987
RADIO CHANNEL ARRANGEMENT CONVEYING TRANSMIT POWER LEVEL INFORMATION
by Marie Shanley and Joseph Downey
In amicrocomputer-controlled multi-channel radio which can transmit at different power levels, some con- venient method is needed to select what power level is to be used on a given channel. One method is to arrange the channels internally into several groups with a different power level assigned to each group.
Consider a radio with N channels and M different power levels (FIG. 1). Channels in the radio may be selected either via channel knob, keypad, or a combination thereof (a channel-zone configuration). Each channel will be assigned an internal number which might not be directly related to the channel knob position. Internal chan- nels will be grouped into M numeric ranges whose boundaries will be read from a table in programmable memory (EEPROM). The bit patterns needed to program the power levels will be stored in an EEPROM array starting at location TRAN-PWR. Channels in the first numeric range will use the data stored at TRAN-PWR, the second range will use TRAN-PWR+ 1, and so on. For example, in a radio with 40 channels and 4 power levels:
Bounds: 12 channels l-12 will use power level at TRAN-PWR
15 channels 13-15 will use power level at TRAN-PWR+l 30 channels 16-30 will use power level at TRAN_PWR+2 40 channels 31-40 will use power level at TRAN_PWR+3
Thus, with this arrangement, any combination...