In this paper, a new topology using the common-source amplifier, which is a unilateral component and the directional coupler, is proposed to realize an isolator without ferrite. The theory and the design procedures are presented. The performance of this isolator is comparable to those of the ferrite isolators, except for the bandwidth. The 1-dB compression point of output power $({\rm OP}_{1{\rm dB}})$ of the insertion loss is high due to the passive nature of the directional coupler, but the reverse isolation deteriorates with the increasing input power. The proposed 24-GHz monolithic microwave integrated circuit isolator is developed in TSMC 180-nm CMOS. Based on the proposed isolators, a quasi-circulator is designed and fabricated. Both the isolator and quasi-circulator have better ${\rm OP}_{1{\rm dB}}$ of the insertion loss than reported active isolators and quasi-circulators.

Design and Analysis of 24-GHz Active Isolator and Quasi-Circulator

Hybrid wired-wireless Network-on-Chip (WiNoC) has emerged as an alternative solution to the poor scalability and performance issues of conventional wireline NoC design for future System-on-Chip (SoC). Existing feasible wireless solution for WiNoCs in the form of millimeter wave (mm-Wave) relies on free space signal radiation which has high power dissipation with high degradation rate in the signal strength per transmission distance. Moreover, over the lossy wireless medium, combining wireless and wireline channels drastically reduces the total reliability of the communication fabric. Surface wave has been proposed as an alternative wireless technology for low power on-chip communication. With the right design considerations, the reliability and performance benefits of the surface wave channel could be extended. In this paper, we propose a surface wave communication fabric for emerging WiNoCs that is able to match the reliability of traditional wireline NoCs. First, we propose a realistic channel model which demonstrates that existing mm-Wave WiNoCs suffers from not only free-space spreading loss (FSSL) but also molecular absorption attenuation (MAA), especially at high frequency band, which reduces the reliability of the system. Consequently, we employ a carefully designed transducer and commercially available thin metal conductor coated with a low cost dielectric material to generate surface wave signals with improved transmission gain. Our experimental results demonstrate that the proposed communication fabric can achieve a 5 dB operational bandwidth of about 60 GHz around the center frequency (60 GHz). By improving the transmission reliability of wireless layer, the proposed communication fabric can improve maximum sustainable load of NoCs by an average of $20.9$ and $133.3$ percent compared to existing WiNoCs and wireline NoCs, respectively.

/pdf/a-resilient-2-d-waveguide-communication-fabric-for-hybrid-4s38gez68r.pdf

A Resilient 2-D Waveguide Communication Fabric for Hybrid Wired-Wireless NoC Design

A three-port active circulator and an active quasi-circulator (QC) based on bridged-T networks (BTNs) are designed and fabricated in a standard 0.18- $\mu \text{m}$ CMOS technology. The BTN provides a notch frequency response, and therefore, the circulator is practical by connecting three BTNs in a ring-type configuration. With a power consumption of 18.2 mW, the circulator achieves $6.1\sim 8$ -dB insertion loss, better than 25-dB isolation and 18.3-dB transmission ratio from 8.4 to 11.1 GHz. Furthermore, the QC based on one BTN topology can also be obtained by adding an external amplifier. With a power consumption of 18.6 mW, it achieves 7/−2-dB forward transmission gain, better than 17.3-dB isolation, and better than 15.3-dB transmission ratio at 9.9 GHz. The presented designs feature excellent performances in high isolation and transmission ratio compared with other CMOS active circulators or QCs. To the best of our knowledge, the designs are the first demonstration of three-port circulator/QC designs based on the BTN topology, and the design concept is also applicable to an $n$ -port circulator design.

Fully Integrated 10-GHz Active Circulator and Quasi-Circulator Using Bridged-T Networks in Standard CMOS

In this contribution a hybrid active quasi-circulator operating in L-Band is presented. E-pHEMT active devices mounted on ceramic substrate with copper metallization have been used. The proposed quasi-circulator is composed by active non-reciprocal phase shifters and classical passive combining structures to get the desired functionality. Insertion losses better than 2.1 dB, isolation higher than 20 dB in the 1.35 ÷ 1.65 GHz frequency band is obtained, while an isolation better than 30 dB over a 15% bandwidth. Port matching is better than 15 dB on coupler's ports, while the splitter one reaches 10 dB. The overall quasi-circulator exhibits a 22 % operating bandwidth.

A novel hybrid active quasi-circulator for L-band applications

Ferrites are the traditional materials used in conventional passive circulators [1]-[3]. One of the first ferrite microwave circulators was the Faraday rotation circulator, which is based on Faraday rotation, the phenomenon that occurs when microwaves of a specific polarization are incident upon a ferrite material subjected to a magnetic field parallel to the direction of propagation. These circulators were later replaced by resonance isolators and differential phase shift circulators, which have higher power-handling characteristics and are simpler to construct. In 1964, the lumped-element circulator [4] was brought to the attention of the microwave industry. The lumped-element Y circulator uses ferrite and has a mesh mechanism in place of the ordinary strip-line circulator?s center conductor. Ferrites are too expensive and bulky for practical use in integrated circuits.

The Challenge of Active Circulators: Design and Optimization in Future Wireless Communication

This paper introduces two new type active quasi circulators and three new type active circulators which use the out- of-phase power divider/combiner, symmetric/anti-symmetric couplers and generic unilateral ampliflers. The proposed circuits are full-symmetric and composed of conventional microwave devices. Analytical relations for active quasi circulator modules are described. These modules have many variations and can be used for very wide frequency range depending on the type of the employed unilateral amplifler, power divider/combiner and symmetric/anti-symmetric couplers. Based on the proposed conflgurations, analysis and design of n-port active circulators are presented. Also they can be used in MMICs as active quasi circulators, active circulators and in other high frequency applications.

/pdf/analysis-and-design-of-new-active-quasi-circulator-and-1zr8hqat1e.pdf

Analysis and design of new active quasi circulator and circulators

A novel active quasi circulator module design is proposed. In addition to its small size and operation over a wide frequency range, it has different bandwidths and performance because of using different kinds of unilateral amplifiers. The proposed active quasi circulator circuit is a result of the modular design approach. In this circuit, a matrix amplifier is employed to construct the proposed QCM. The active circulator is designed by combining QCMs, and QCM is designed by combining the matrix amplifiers. The simulation result of designed QCM and active circulator shows that the gain, isolation and return loss of these modules are better than other modules.

Design a new type of active quasi circulator module

This paper presents the design and simulation of a typical Ka band satellite beacon receiver for propagation experimentation. Using satellite beacon signal as a reference signal in satellite wave propagation study is one of the most important methos. Satellite beacons are frequently available for pointing large antennas, but such signals can be used for measuring the effect of natural phenomena such as atmospheric gases, water vapor, oxygen molecules, clouds, rain, dust and fog existing in different layers of the atmosphere, including troposphere and ionosphere.

http://jacet.srbiau.ac.ir/article_6709_3dbc16f554dbe4a2454e83efb15e6103.pdf

Typical Ka band satellite beacon receiver design for propagation experimentation

This paper studies the development of a full Bayesian version of binary logistic model for analysis of 99.99% satellite link availability at Ka-band over Iran. To satisfy target availability requirements, several tens of dBs would have to be compensated in the process of system design with a static margin, which is possible only up to some threshold value due to technology limitations or interference to adjacent links constraints. Binary attenuation data are obtained by dividing rain attenuation values exceeded for 0.01% of an average year (A 0.01 ) for 287 different locations over Iran, into two categories according to imposed critical limiting threshold at each frequency. Through the proposed binary logistic model, the possible effects of explanatory variables on reaching the A 0.01 above the critical threshold are investigated. The variables include geographic regions, employed satellite, height above sea level, and rainfall as well as the interaction between geographic regions and satellite. The possibility of existence of the interaction effects for rainfall explanatory variable is investigated by constructing an extended model which includes the interaction between rainfall and other variables. The results of these two models are compared via some Bayesian Criteria (DIC) which confirmed the superiority of the extended model.

http://ieeexplore.ieee.org/iel5/6389597/6402923/06403033.pdf

A MCMC Bayesian approach to binary logistic model for Ka-band propagation effect by rain over Iran

Analysis and design of three novel active quasi-circulator modules are presented, which use the nonreciprocal properties of microwave unilateral power divider/combiner and amplifiers.These modules have many variations and can be used for very wide frequency range depending on the type of the unilateral amplifier used. Also, they can be used in MMICs as active circulators and also in other high-frequency applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 689–694, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24998

Reza Bahri

Papers

Analysis and design of new active quasi circulator and circulators

Design a new type of active quasi circulator module

Typical Ka band satellite beacon receiver design for propagation experimentation

A MCMC Bayesian approach to binary logistic model for Ka-band propagation effect by rain over Iran

Design of three new types of active quasi‐circulator modules