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User:S.sunilpal123/Cell size breathing

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Cell size breathing is the concept in telecommunications that leads to a shrinkage in the effective cell size due to the addition of extra user(s) to the ones already using the existing resources.

This phenomenon is more pronounced and easy to understand if the reader is familiar with CDMA technology. In CDMA, power control is employed so that Near-far problem does not compromise a CDMA cell edge user's right to gain access to the base station. It is thus of paramount importance that an edge user transmit at higher power and a nearer user at lower power. Given that a cell is already working at optimum received power per user, all the users are already transmitting at powers (different from each other) and still creating manageable intra-cell interferences; the addition of more users to this precarious cell creates a strain both on the users as well as the base station to overcome the extra interferences. Power per user is essentially decreased at the base station to accommodate the extra users, since in CDMA power of BTS is shared among users. Since power decreases the cell coverage in the downlink decreases and cell shrinkage results. In effect, now the users have to be closer to the BTS to get same quality of reception.