Sennheiser Sets New Standards for High-End Audio Receivers Using AWR Software


The Design Challenge

The RF spectrum in music halls and concert venues is becoming more and more crowded with multiple, simultaneous frequencies and channels. Sennheiser audio equipment is used by many famous recording artists worldwide, and they rely on Sennheiser to help them deliver high quality performances. Therefore, our concert audio receivers must be able to function in this environment and produce excellent sound with no interference.

The Solution

In order to ensure that our EM 3732 audio receiver would function without interference and deliver the quality of sound required, we designed a varactor-tuned bandpass filter thats contained within the preselector of the receiver. The intermodulation behavior of this filter plays a key role in the receiver design, and with Microwave Office® software we were able to achieve +20dBm IP3, thus meeting the strict system requirements necessary for the desired performance.

We were able to use the AWR design flow exclusively for the entire design cycle, from the system design, through the circuit design (DC, time-domain, audio, RF noise, and layout), all tasks during the design cycle (verification by measurement, controlling measurement equipment, extracting measurement-based sub circuits, centering of circuits), and, finally, production aspects such as yield optimization. For all the simulations we used the Microwave Office APLAC® RF simulator. No other simulator on the market provides such a comprehensive and flexible set of features as APLAC.