Columbia Technology Ventures

Spatial equalization of in-band signals in wireless receivers

This technology is a semiconductor-based communication circuit that spatially equalizes incoming and outgoing radiofrequency signals, allowing for reduced antenna sizes without loss of performance in transmission and receiving.

Unmet Need: Spatial equalization of radiofrequency signals for CMOS-integrated circuits

Wireless communications have become a mainstay in consumer, industrial, and military technology. A key function of a wireless receiver is the ability to separate incoming and outgoing signals to avoid interference, typically accomplished using external, iron-based magnets that spatially separate the signals. However, these iron-based circulators are bulky, expensive, and incompatible with CMOS technology. As such, there is a need for an alternative strategy to achieve spatial equalization for CMOS-integrated circuits.

The Technology: Transistor-based CMOS-compatible circulator

This technology is a four-transistor circuit that is precisely clocked to route incoming and outgoing radiofrequency signals in the appropriate direction, allowing these signals to achieve spatial equalization on the same circuit while utilizing the same antenna. This technology enables smaller devices that perform the task of a circulator without the large magnetic components. Importantly, this technology is compatible with standard integrated circuit processing techniques.

A prototype of this technology, consisting of a fully integrated 25-GHz circulator in a 45-nm SOI CMOS, demonstrated magnetic-free passive non-reciprocity on silicon at millimeter waves.

Applications:

  • Cell phone communication
  • Radio signaling
  • Small robotics
  • Aerospace electronics
  • Wearable electronics

Advantages:

  • Compatible with CMOS-integrated circuit fabrication techniques
  • Small and lightweight
  • Low power consumption
  • Matches the performance of iron-based circulators

Lead Inventor:

Harish Krishnaswamy, Ph.D.

Patent Information:

Patent Issued

Related Publications:

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