A new thin film passive integration technology for miniaturisation of mobile phone front end modules: integration of a dual-band power amplifier, switch and diplexer for GSM

The use of a new thin film substrate technology for integrating the critical passive parts of RF-circuits of mobile communication equipment is demonstrated. A very compact module that contains two power-amplifiers, two receive/transmit-switches and a diplex-filter for dual-band GSM mobile phone applications was designed, manufactured and tested in order to demonstrate the miniaturisation possibilities with this technology. With a size of 160 sq. mm, the module meets the GSM output power specifications (2 W at 900 MHz and 1 W at 1800 MHz) and the harmonic attenuation requirements. The realised insertion loss of less then 1.5 dB in the receive- and transmit chain together with a receive-transmit-isolation of over 20 dB is sufficient for most GSM applications.