OREANDA-NEWS. February 27, 2012. TDK-EPC, a group company of TDK Corporation, presents two new EPCOS duplexers with greatly improved linearity values. The B7654 type was developed for CDMA applications, the B7928 type for LTE Band 13. The combination of both duplexers in a mobile phone allows the simultaneous transmission of voice and data. Thanks to the high linearity achieved, the sensitivity in the input paths was increased. This allows developers of mobile phones to significantly simplify the architecture of the RF input circuit because additional components for linearization are not needed.

Duplexers of the B7654 type are designed for the frequency band from 824 to 849 MHz in transmit operation (TX) and from 869 to 894 MHz in receive operation (RX). Attenuation of up to 57 dB is attained between the transmit and receive bands. Interfering GPS frequencies are attenuated by 40 dB.

The B7928 type is designed for the frequency band from 777 to 787 MHz in transmit operation (TX) and from 746 to 756 MHz in receive operation (RX). Attenuation of up to 62 dB is attained between the transmit and receive bands. Interfering GPS frequencies are attenuated by 45 dB.

Despite their outstanding performance features, these duplexers have dimensions of only 2.5 x 3.0 mmІ. Series production is scheduled to begin in the second quarter of 2012.

Glossary
Duplexers: key components for LTE and UMTS mobile phones and data cards. They combine a transmit and a receive filter for simultaneous transmission and reception in a specific frequency band.
LTE: stands for Long Term Evolution and is a 4G mobile communications standard. It allows significantly higher data rates than with UMTS.

Main applications
Mobile phones, smart phones and data cards.

Main features and benefits
Good linearity leads to higher sensitivity.
High attenuation values between the transmit and receive path, and high attenuation of
GPS frequencies.