January 01, 2018

Compact High Isolation Base-Station Duplexer Using Triple-Mode Ceramic Cavities

  • Abbosh A.
  • Hendry D.

A microwave duplexer with high isolation is presented. The device is based on triple mode filters that are built using silver plated ceramic cuboids. To create a six-pole, six-transmission zero filter in the DCS-1800 band, which is utilized in mobile communications, two cuboids are cascaded. To shift spurious harmonics, low dielectric caps are placed on the cuboid faces. These caps push the first cuboid spurious up in frequency by around 340 MHz compared to the uncapped cuboid, allowing a 700 MHz spurious free window. To verify the design, a DCS-1800 duplexer with 75 MHz wide bands is built. It achieves around 1 dB of insertion loss for both the receive (Rx) and transmit (Tx) ports with around 70 dB of mutual isolation within only 20 MHz band separation, using a volume of only 30 cm3.

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Recent Publications

August 09, 2017

A Cloud Native Approach to 5G Network Slicing

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5G networks will have to support a set of very diverse and often extreme requirements. Network slicing offers an effective way to unlock the full potential of 5G networks and meet those requirements on a shared network infrastructure. This paper presents a cloud native approach to network slicing. The cloud ...

August 01, 2017

Modeling and simulation of RSOA with a dual-electrode configuration

  • De Valicourt G.
  • Liu Z.
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Based on the physical model of a bulk reflective semiconductor optical amplifier (RSOA) used as a modulator in radio over fiber (RoF) links, the distributions of carrier density, signal photon density, and amplified spontaneous emission photon density are demonstrated. One of limits in the use of RSOA is the lower ...

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  • Christof Fetzer
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How to preserve users' privacy while supporting high-utility analytics for low-latency stream processing? To answer this question: we describe the design, implementation and evaluation of PRIVAPPROX, a data analytics system for privacy-preserving stream processing. PRIVAPPROX provides three properties: (i) Privacy: zero-knowledge privacy (ezk) guarantees for users, a privacy bound tighter ...