Columbia Technology Ventures

CMOS-based radio frequency circulator for full-duplex communication systems

Non-reciprocal radio frequency (RF) components, such as circulators, can enable full-duplex communication – the ability to transmit and receive signals simultaneously on the same frequency channel. This emerging form of communication could hypothetically double wireless network capacity. However, non-reciprocal circulators are typically magnetic materials that cannot be integrated onto a silicon chip. Furthermore, magnetic circulators are limiting in terms of their size, weight, and cost, collectively rendering such materials impractical for use in wide-spread communication devices. This technology is a CMOS-based, non-magnetic circulator that surpasses these limitations and can therefore be implemented in full-duplex communication applications.

Non-magnetic, high-performance circulators that can be implemented in integrated circuits

This technology implements non-reciprocity in an integrated circuit (IC) without the need for magnetic materials. Utilizing N-path filters that leverage the high-speed switching capabilities of transistors, non-reciprocity can be achieved. While this technology can advance IC integration in full-duplex systems, these CMOS-based circulators grant high isolation, have low losses, and provide a reduced form factor that not only reduces cost and design complexity, but also facilitates design of a shared interface between the antenna, transmitter, and receiver. Additional benefits of this technology are its blocker suppression capability and enhanced linearity of the transmitter port, which can be critical for high-power transmitters.

A prototype of this technology was successfully demonstrated and tested, exemplifying its high performance and potential for advancing full-duplex communication systems.

Lead Inventor:

Harish Krishnaswamy, Ph.D.

Applications:

  • Full-duplex communications
  • 5G communication networks
  • Radar applications
  • Optical switches

Advantages:

  • Allows for design of a shared interface between the antenna, transmitter and receiver
  • Magnetic-free nature and compatibility with IC integration
  • Compact form factor
  • Enables cost reduction and simplified design
  • High performance in terms of low loss and high isolation
  • Facilitates high-power transmission with high linearity
  • Real-time reconfigurability to switch from full-duplex (non-reciprocal) to half-duplex (reciprocal) mode
  • Enables blocker suppression

Patent Information:

Patent Issued

Tech Ventures Reference: IR CU16158

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