The dynamic range enhancement technique applied to an AMPS and CDMA cellular environment

The need for extremely low cost cellular systems in the PCS band can be accomplished by remote antennas which collect the radiated RF signals and forward the composite received signal over an optical fiber link to a central location for processing. Analog modulation of the RF signal for transmission over the fiber is less complex and potentially less expensive, but the drawback is the dynamic range limitation of the laser modulator. A new approach for enhancing the dynamic range of a signal that is limited by the dynamic range of the interface to the transmission channel has been introduced. This approach, called the dynamic range enhancement technique (DRET), is well suited to overcome the remote antenna performance limitation and for other similar applications. This paper evaluates and compares the performance of the DRET to the AGC approach, applied to a mixture of direct sequence spread spectrum (DS/SS) signals and AMPS signals, for dynamic range enhancement of the RF to fiber interface.