MIT engineers have built a fast, ultra- broadband, low-power radio chip, modelled on the human inner ear, that could enable wireless devices capable of receiving cell phone, Internet, radio and television signals. Rahul Sarpeshkar, associate professor of electrical engineering and computer science, and his graduate student, Soumyajit Mandal, designed the chip to mimic the inner ear, or cochlea. The chip is claimed to be faster than any human-designed radio-frequency spectrum analyser and also operates atmuch lower power.
The engineers have filed for a patent to incorporate the RF cochlea in a universal or software radio architecture that is designed to efficiently process a broad spectrum of signals including cellular phone, wireless Internet, FM and other signals.
The RF cochlea mimics the structure and function of the biological cochlea, which uses fluid mechanics, piezoelectrics and neural signal processing to convert sound waves into electrical signals that are sent to the brain.
As sound waves enter the cochlea, these create mechanical waves in the cochlear membrane and the fluid of the inner ear, activating hair cells (cells that cause electrical signals to be sent to the brain). The cochlea can perceive a 100- fold range of frequencies — in humans,
MIT radio chip from 100 to 10,000 Hz. Sarpeshkar used the same design principles in the RF cochlea to create a device that can perceive signals at million-fold higher frequencies, which includes radio signals for most commercial wireless applications.