Filtros para un cabezal de comunicaciones entre vehículos

Abstract

In this paper two reconfigurable bandpass filters able to switch between WiFi and UMTS for transmit and receive band standards are presented. The filters are designed in such a way that center frequency and bandwidth specifications are precisely met by defining two switchable filter topologies. Design specifications require two center frequency states, one at 2.440 GHz with an 80 MHz bandwidth and a second center frequency state at 1.955 GHz with a 140 MHz bandwidth for the WiFi and UMTS transmit bands. The second filter is able to have one center frequency at 2.440 GHz with an 80 MHz bandwidth and a second center frequency state at 2.165 GHz with a 110 MHz bandwidth for the WiFi and UMTS receive bands, respectively. Filter simulations were performed to match the required filters specifications. Measured results on the transmit filter show a very good agreement with the simulations where a 2.428 GHz center frequency with a 71 MHz bandwidth was obtained for the WiFi state, and a 1.939 GHz center frequency with a 144 MHz bandwidth was obtained for the UMTS filter state. Simulated results on the receive filter show a very good agreement with the specified parameters. The filters specifications were successfully matched with the proposed filter topologies.