Noise reduction communication circuits

The demand for longer battery life and faster speeds for communications circuits coupled with the exponential expansion of wireless communications devices is creating increasingly serious noise problems for communications circuits. Longer battery life means lower power consumption usually obtained by reduced noise margins that can only be achieved by better circuit design, but at least this under the designer´s control. Demand for more spectrum by the explosion of wireless devices creates noise sources outside the designer´s control that must be dealt with by increasingly clever noise attenuation circuits. This paper will review the state of the art for adaptive filtering as applied to external noise attenuation in communication circuits highlighting the most promising technologies including adaptive heterodyne filters.