Scientists have announced a new research breakthrough they say could increase the range of wireless frequencies available in smartphones and other wireless devices while simultaneously reducing manufacturing costs.
Researchers at Northeastern University, in cooperation with Semiconductor Research Corporation (SRC), found that the application of a certain amount of voltage to a piezoelectric layer on an integrated magnetic inductor changed the permeability of the inductor’s magnetic core. As the permeability of the magnetic core is altered, the inductance of the inductor is also changed, which in turn tunes the resonance frequency in a capacitor-inductor circuit.
Currently, radio frequency circuits in smartphones and other similar wireless devices rely on tuning radio frequency (RF) varactors to find available frequencies for transmission, which limits tunable frequency range. Allowing tuning in inductors as well could enhance a smartphone’s tunable frequency range from 50 percent to 200 percent and double the number of channels available in a single RF module, according to Nian Sun, associate professor of electrical and computer engineering at Northeastern University.
“These voltage-tunable RF inductors constitute a new RF tuning technology that will lead to significantly enhanced tuning range and reduced RF circuit modules,” Sun told Computer World. “We expect the new inductors to bring about revolutionary changes in tunable RF circuit designs, which will result in higher quality smart phones with lower costs and more compact size.”
“Researchers have been trying a while to make inductors tunable—to change the inductance value—and haven’t been very successful,” Kwok Ng, senior director of device sciences at SRC, said, adding that the new tunable inductors could be used to improve radio signal performance, reducing the number of modules needed in smartphones and other wireless devices.
Representatives from Semiconductor Research Corporation (SRC) and Northeastern University in Massachusetts presented their findings at the 58th Magnetism and Magnetic Materials Conference in Denver, Colo. earlier this month. Intel and Texas Instruments also participated in the research.
The new inductor technology is expected to be developed further by the middle of next year, with implementation planned in consumer applications by as early as late 2014.
