www.WirelessFederation.com/news: A prototype multi-band power amplifier accommodating eight frequency bands between 700 MHz and 2.5 GHz has been developed by Japan’s DoCoMo. The amplifier will pave the way for all in one, lightweight mobile phones capable of standalone wireless communications of different standards, including the forthcoming LTE standard as well as existing W-CDMA and GSM.

A separate single-band amplifier for each band will increase the size of the phone to accommodate new frequency bands for LTE services being launched in markets worldwide.  The gain and output power of DoCoMo’s new amplifier is equivalent to conventional single-band amplifiers.

It employs matching circuits whose frequency characteristics are controlled by multiple semiconductor switches according to the required frequency band and hence enables 8- band operation. Power amplifiers are used in mobile phones to increase signal power up to levels required for wireless communication.