Unlike in the GSM system where the distinction between a cell with other cells is determined by the frequency carrier used. In a CDMA system the difference between a cell with other cells located in the PN offset. If the PN offset allocation is not right it will lead to the identification of cells that ambiguity serves a terminal MS. PN offset should be made so that the cells did not interfere with each other nearby.
PN offset index is available in a CDMA system is a unique value 512. Between PN offset index to each other 64 different chips, so that the total period is 32,768 chips. One chip itself costs about 0814 microseconds. When a pilot signal moves from one cell to the MS there will be delay. Minimum delay between an offset with other offset allowed is 64 chips = 4:09 xd (kilometers). Thus produced interfal one PN offset index is about 15.6 km.
If the signals from two cells that happened to have the adjacent PN offset having the propagation delay to an MS there will be ambiguity PN offset detection. MS would be difficult to acquire the system because they do not know which cells are actively serve. In the figure below illustrated that the two pilot signals from two cells that have the index of adjacent PN offset received by the MS in 64 chip intervals. Receiver system in MS would be puzzled to decide which functions as the cells are active cells and which candidate cells. When the signal originating from the active cell is considered as a candidate cell or the neighbor cell handoff command could not be done as a result when the conditions call (busy) will be dropped call.
New CDMA operators have never had previous experience, is usually trapped in the paradigm of GSM-based cellular networks. Or also because the campaign does not require the design bahwaCDMA radio without thinking of the PN offset allocation, the main pairs of base stations regardless of their impact. Indeed in the CDMA system does not require radio design but the design requires the allocation of PN offset for each cell to avoid polution pilots. If this has happened what should be done such service? The answer is to plan for re-re-use PN offset by the cells - cells that have on the network. Final goal of this effort is to make the same PN offset or not close interplay between these cells by regulating the distance
PN offset index is available in a CDMA system is a unique value 512. Between PN offset index to each other 64 different chips, so that the total period is 32,768 chips. One chip itself costs about 0814 microseconds. When a pilot signal moves from one cell to the MS there will be delay. Minimum delay between an offset with other offset allowed is 64 chips = 4:09 xd (kilometers). Thus produced interfal one PN offset index is about 15.6 km.
If the signals from two cells that happened to have the adjacent PN offset having the propagation delay to an MS there will be ambiguity PN offset detection. MS would be difficult to acquire the system because they do not know which cells are actively serve. In the figure below illustrated that the two pilot signals from two cells that have the index of adjacent PN offset received by the MS in 64 chip intervals. Receiver system in MS would be puzzled to decide which functions as the cells are active cells and which candidate cells. When the signal originating from the active cell is considered as a candidate cell or the neighbor cell handoff command could not be done as a result when the conditions call (busy) will be dropped call.
New CDMA operators have never had previous experience, is usually trapped in the paradigm of GSM-based cellular networks. Or also because the campaign does not require the design bahwaCDMA radio without thinking of the PN offset allocation, the main pairs of base stations regardless of their impact. Indeed in the CDMA system does not require radio design but the design requires the allocation of PN offset for each cell to avoid polution pilots. If this has happened what should be done such service? The answer is to plan for re-re-use PN offset by the cells - cells that have on the network. Final goal of this effort is to make the same PN offset or not close interplay between these cells by regulating the distance
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