Lab Director: Yannis Tsividis, Ph.D.
STV Reference: MS99/02/13
Problem or Unmet Need
A crucial component of single-chip wireless RF transceivers are continuous-time filters. These filters require automatic tuning systems, which correct time constants and help achieve manufacturing tolerances. A popular approach to this problem uses voltage-controlled oscillators (VCO) to set the time-constant for the tracking filter. This approach requires amplitude regulation, which is necessary to keep the amplitude small. However, for GHz-range coupled-resonator band-pass filters, both these approaches have been found to be ineffective.
Details of the Invention
This invention overcomes the limitations of the existing approach by employing a novel feedback circuit and using an envelope detector. The invention achieves automatic tuning and loss control in VCO master-slave systems and robust amplitude regulation.
Applications:
Automatic tuning systems are at the heart of VCO and the proposed technology working in the GHz range can be employed in a wide variety of applications: • Cellular handsets • Wireless Local Area Networks • HiperLAN (Hi-performance radio LAN) • Bluetooth (wireless Personal LAV) • HomeRF • Broadcast Radio • Broadcast TV
Advantages:
• Works in the GHz range for couple resonant band-pass filters
Patent Status: US Patent 6,137,375
Publications: Li D, Tsividis Y. “A novel loss control feedback loop for VCO indirect tuning of RF integrated filters” IEEE International Symposium on Circuits and Systems. 1998 May 31-3 June 3: 135-138.
Licensing Status: Available for Licensing and Sponsored Research Support