CDMA reverse link open loop power control

An open-loop power control algorithm for code-division multiaccess (CDMA) cellular mobile telephony is presented. The algorithm is optimum in the sense of minimizing the mobile transmitted power and hence reduces the level of interference. Normally, the open-loop power control is used to mitigate long-term variations. The mobile unit measures the total received power and uses the measurement to estimate the transmission loss. This estimate is used to permit a rapid response to changes in the channel characteristics. It is shown that the open-loop mobile transmitted power is inversely proportional to its total received power. The constant can be part of a broadcast message that it is sent by the home cell. It is shown that the constant is sensitive to system parameters such as the cell effective radiated power (EPR), noise figure, antenna gain, the set of E_b/N_t , and system loading. The open loop should have a large dynamic range (80 dB) and a reasonable fast response in order to accommodate subscriber units passing behind buildings or subject to shadowing effects. Data collected from both the laboratory and field tests support the analytical results presented