SRCH_WIN_A, SRCH_WIN_N, and SRCH_WIN_R
Application: SRCH_WIN_A, SRCH_WIN_N, and SRCH_WIN_R are the search window sizes in the active pilot set, the neighbor pilot set, and the remaining pilot set respectively. The search window sets the range around the earliest arriving usable multipath component of the pilot. That is, a pilot search window of size 28 means that the search should occur ±14 chips from the earliest arriving usable multipath. The candidate set search window size equals the active set search window size.
The search window size is expected to be larger in cells where the distance to a usable base station may be large. The spread of useful multipath components is expected to be largest in dense urban regions where there is more multipath to provide a larger interval of time over which useful multipath components might be received. Search window sizes which are too large, slow down the searching procedure at the mobile by forcing it to search at time-delays at which it is very unlikely that usable pilot power will be found. Setting the search window size too small, may cause a pilot to be missed. This serious error, may result in their being no usable pilot in the active pilot set.
SRCH_WIN_A, SRCH_WIN_N, and SRCH_WIN_R
Example: Table 6.6.6.2.1-1 of IS-95 gives the search window sizes in numbers of PN chips to be searched. Search window sizes range from 4 chips to over 200 chips. The propagation distance from a base station to a mobile may be up to about 10 miles. This corresponds to up to about 64 PN chips. Hence, the search window may need to be on the order of ±64 chips. Smaller propagation distances allow smaller windows. Typically, search window sizes would be expected to be less than about 64 PN chips.
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