Val Dyadyuk

A Multigigabit Millimeter-Wave Communication System With Improved Spectral Efficiency

This paper describes the details of a new method for improved spectral efficiency in a multigigabit millimeter-wave communication system, and the outdoor and indoor test results of a 6-Gbit/s concept demonstrator in the 81-86-GHz frequency band. Achieved aggregate data with a 2.4-bit/s/Hz spectral efficiency was the fastest wireless transmission published thus far with a carrier-grade bit error rate over a millimeter-wave link.

A multi-gigabit microwave backhaul

The rapid growth of multimedia broadband wireless services has placed huge pressure on the backhaul infrastructure. As cost-effective alternatives to fibre backhauls, high speed microwave backhauls provide a number of significant benefits, especially for bringing broadband services to rural and regional areas. This article addresses the challenges to wireless backhauls and presents a multi-gigabit microwave backhaul system, called Ngara backhaul, which is being developed at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia. The various innovative aspects of the Ngara backhaul system including spectrum aggregation, peak-toaverage power ratio reduction, out-of-band emission cancellation, and sample rate conversion, are reported.

Multi-gigabit wireless communication technology in the E-band

The enabling technologies and challenges in development of multi-gigabit wireless communication systems in the E-band are discussed. Potentials of the further improvement of the fixed wireless links performance and feasibility of development of the future ad-hoc or mobile wireless networks in the E-band are evaluated.

Integrated W-band GaAs MMIC Modules for Multi-Gigabit Wireless Communication Systems

70-90 GHz integrated receive and transmit modules with sub-harmonic frequency translation were developed using a GaAs MMIC chip set. These have a reported -3 dB bandwidth above 9 GHz and 6 GHz respectively for the down-converter and up-converter. With a common 39.25 GHz LO frequency, the modules are well suited for the RF transceivers of full-duplex wireless communication systems operating in both 71-76 and 81- 86 GHz bands using the lower or upper side-band conversion in each chosen (receive or transmit) direction.

W-Band GaAs Schottky Diode MMIC mixers for Multi-Gigabit Wireless Communications

This paper describes the design and measured performance of wideband sub-harmonically pumped mixers suitable for the millimeter-wave multi-gigabit wireless communication systems. It represents the first development of W-band mixers using a commercial Schottky diode process published so far.

Improved spectral efficiency for a multi-gigabit Mm-wave communication system

This paper describes a novel method for improving spectral efficiency in a multi-gigabit mm-wave communication system, and test results of a 6 gigabit per second concept demonstrator in 81-86 GHz frequency band with a 2.4 bits/s/Hz spectral efficiency. Achieved aggregate data was the fastest wireless transmission worldwide with a carrier-grade bit error rate over a mm-wave link using a spectrum efficient modulation method.

Demonstration of Adaptive Analogue Beam Forming in the E-Band

In this paper, we report the test results of a small-scale prototype that implements an analogue-beam-formed phased antenna array in the E-band. A four-channel dual-conversion receive RF module for 71~76 ㎓ frequency band has been developed and integrated with a linear end-fire antenna array. Measured performance is very close to the simulated results. An ad-hoc wireless communication system has also been demonstrated. Low BER was measured for an 8PSK data stream at 1.5 Gbps with the receive array beam formed in the direction of arrival of the transmitted signal. To our knowledge this is the first steerable antenna array reported to date in the E-band.

Low loss FSS polarizer for 70 GHz applications

A dual-layer low loss transmission type FSS polarizer is presented for 70 GHz applications. For high frequency applications, the transmission loss through polarizer becomes a critical issue and therefore techniques are required to reduce it. The concept of Fabry-Perot Interferometer is used to design dual-layer polarizer by which the transmission loss has been reduced to 0.3 dB at resonance frequency. The FSS polarizer consists of a cross-dipole aperture in a metal sheet having different arm lengths in x- and y- directions. Theoretically 100% circular polarization is achieved at the centre frequency.

Frequency-Domain Digital Calibration and Beamforming with Wideband Antenna Array

This paper presents a joint channel and mutual coupling estimation technique for wideband antenna array to achieve high speed wireless communications in the millimetre-wave frequency bands. The estimated channel frequency responses and mutual coupling matrix can be used to digitally calibrate a wideband antenna array in the frequency-domain, followed by digital beamforming. Experiments are carried out using a four-element receive array prototype in the E-band (71-76 GHz) to demonstrate the frequency-domain digital calibration and beamforming performance. The results show that both the mutual coupling and wideband effects are effectively mitigated by the proposed technique and a 11.5 dBi array gain is achieved which is very close to that of an ideal four-element antenna array.

A 6 Gbps Millimetre Wave Wireless Link with 2.4 bit/Hz Spectral Efficiency

An all electronic 6 Gbps millimetre wave point-to-point link in the 85 GHz band has been developed. The complete link has been built including RF, IF and digital baseband modules. 8PSK (phase shift keying) modulation has been used to achieve 2.4 bit/Hz spectral efficiency. According to our knowledge this is the highest spectral efficiency to date for a millimeter wave link with a demonstrated 6 Gbps data rate. In this paper we report measured performance of the millimeter wave radios and the link on an outdoor test range of 250 m.