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    CDMACH

    Definition: CDMACH is the CDMA Channel number currently being used by the mobile station. CDMACH is an 11-bit number corresponding to the center frequency of the approximately 1.25 MHz CDMA physical channel communications band-width.

    A related parameter is the 11-bit CDMA_FREQ data word which the base station uses to inform the mobiles which CDMA channels are available. The CDMA_FREQ is the CDMA channel number needed by the receiver to tune its front end. In contrast with CDMACH and CDMA_FREQ, the particular Walsh code word to be used by the mobile is assigned using CODE_CHAN, which is a binary number equal to a decimal number from 1 to 63 inclusively.



    CDMACH

    Example: The terrestrial cellular band from 824 MHz to 894 MHz is subdivided into 30 kHz channels. Each of these channels is assigned a number. For instance, the channel number for the primary CDMA Channel transmitted by base sta-tions in Band B is 384. The corresponding center frequency in MHz is given in the IS-95 standard to equal .030(384) + 870.000 or 881.52 MHz. An 11-bit binary equivalent to decimal 384 is binary 00110000000.



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