Considering Downlink Intermodulation Distortion in Switched Multibeam Antennas for Cellular Radio Systems
نویسنده
چکیده
The performance and feasibility of switched multibeam array antennas in cellular systems is investigated. We assume that multicarrier power amplifiers (MCPA:s) are used in the base-station, to co-amplify the transmitted signals. The MCPA generates intermodulation distortion and it is shown how the multibeam antenna makes the radiated intermodulation distortion dependent on the azimuthal lookdirection. Given the carrier to intermodulation distortion ratio of the MCPA, semi-analytical expression for the outage probability for the mobiles is derived assuming a lognormal fading radio channel. Furthermore, the impact of the frequency reuse factor, trunkpool scheme and number of antennas is investigated. The analysis show that when the number of antennas are increased, it is possible to reduce the requirements on the MCPA linearity.
منابع مشابه
Intermodulation distortion in switched multibeam antennas for cellular radio systems
The performance of switched multibeam antennas for cellular radio systems is investigated when the transmit amplifier is of a multicarrier (MCPA) type. The MCPA nonlinearity generates intermodulation distortion in the transmitted signal that is spatially filtered by the array radiation pattern. Hence, the intermodulation distortion becomes direction-dependent, and the direction of the generated...
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