Overload

Elements of the network have to be able to transmit the peak signal of the multichannel system load.

The system overload requirements are dimensioned such that the probability of the peak busy hour transmission signal exceeding the peak value of a sinusoid signal of power P is 0.01.

P in dBmO is given by Equation 20.33^U1(CCITT, 1985, Supple­ment 22) where t is the activity factor (see Table 20.6); L_q is the channel loading factor (see Table 20.6); and n is the number of active channels.

The value of n is derived from assuming that the probability n channels are active in an N channel system is given by a binomial distribution and that n is only exceeded with a probability of l% (i.e. the value of n is not exceeded 99% of the time) as in Equation 20.34. g is the standard deviation of loud/soft talkers (see Table 20.6) and N the system channel capacity.

P_eq - has been calculated for some of the more important systems, as in Table 20.8.