Rf Front-End Considerations for Future Multiband Mobile Terminals

Abstract

A Radio Frequency (RF) front-end (RF-FE) is one of the keys in multi-mode and multi-band mode mobile terminals. In conventional cellular phones, multiple RF-FEs are installed for multi-band use. There have been a lot of studies of achieving multi-band or broadband circuits that comprise a compact and costeffective multi-band RF-FE with adequate RF performance. Reconfigurable or tunable RF-FEs are a way to provide multi-band function in future mobile terminals, which takes into consideration the capability to support a large number of wireless systems that use different frequency bands. However, the performance degradation should be considered if adaptive circuits are installed in the RF-FE. This paper presents considerations for the issues that might occur in a multi-band RF-FE for future mobile terminals. As an example, a concept of collaboration between a top RF filter and low-noise amplifier (LNA) is presented.