Περίληψη Ομιλίας

All modern high volume radio systems such as cell phones, smart phones or related applications use successfully CMOS devices, as small as 22 nm. The specifications for such “radios” were in part based on the achievable phase noise using cross coupled CMOS oscillator circuits. Here the flicker corner frequency in the order of several 100 KHz to 1 MHz is the limiting cause. In GSM applications the physical next channel (next transmitter) is 600 KHz or 3 channels away. Early base stations had to have better phase noise then the battery operated circuits and now also need to be frequency agile and adaptive. This performance can much easier obtained using discrete SiGe GBT’s , multiple coupled transmission lines and novel noise compensation circuits. Here test equipment quality performance can be demonstrated, i.e covering 2 to 4 GHz or 4 to 8 Ghz with excellent phase noise never possible before. Such low noise numbers, like -150 dBc/Hz at 1 GHz and 10 KHz offset put a huge demand on the test equipment. This educational talk discusses in details modern methods to realize these low numbers and gives insight in the problems of measuring these results and what look for to validate this correctly.

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