John Haine

University of Bristol | UB · Department of Electrical and Electronic Engineering

The progress of wireless communication systems is highly dependent on microwave technologies. With the escalating adoption of higher frequency bands in communication systems and the exponential growth of transistor densities in line with Moore's Law, microwave circuit design complexity and costs are mounting significantly. Machine learning (ML) has...

Tunable duplexers based on self-interference cancellation present a promising alternative to fixed-frequency duplexers (e.g. surface acoustic wave devices), however the level of transmit-to-receive (Tx-Rx) isolation they provide is typically lower compared to acoustic devices. This paper quantifies the impact of reduced isolation on receiver (Rx) n...

Ever since millimetre-wave (mmWave) frequencies were considered as one of the key enabling technologies for fifth generation (5G) mobile communications, due to the availability of spectrum to achieve high data rates, increasing attention has been drawn towards how to evaluate the radiated performance of future 5G mmWave devices. Existing over-the-a...

This paper presents a novel, tunable, frequency-division duplexing radio frequency (RF) front end that combines passive and active self-interference (SI) cancellation. An electrical-balance duplexer is used to passively cancel transmitter noise in the receive band, and an active canceller is employed to suppress SI in the transmit (Tx)-band. Subsys...

This paper analyses the effect of phase noise (PN) on digital non-linear self-interference (SI) cancellation for low delay spread non-linear SI channels typical of small form factor in-band full-duplex (IBFD) radios in indoor environments. Use of a shared local oscillator (LO) between the transmit and receive radios is assumed, and it is shown that...

Electrical balance duplexers (EBDs) present a potential alternative to the fixed frequency duplexing filters used for frequency division duplexing in cellular handset radio frequency front-ends. However the transmit-to-receive (Tx-Rx) isolation can be affected by interaction between the antenna and the environment, and therefore the EBDs balancing...

Electrical Balance Duplexers (EBDs) can achieve high transmit-to-receive (Tx-Rx) isolation, but can be affected by interaction between the antenna and environment. Circuit simulations incorporating measured time-variant antenna impedance data have been used to quantify performance variation and determine circuit adaptation requirements for EBDs ope...

Electrical balance duplexers can provide high transmit-to-receive isolation whilst facilitating transmission and reception from a single antenna, can be implemented on-chip, and are widely tunable, making this an attractive technology for implementing full duplex architectures in small form factor devices. This paper presents measurements from a no...

Exploiting new technologies will be vital in meeting the demanding requirements of 5G radio access. Flexible duplexing architectures will be a key enabling technology in 5G handsets, virtualising the radio spectrum, reducing cost, and increasing link capacity through full duplex radio communication. The tunability, low cost and small form factor of...

Transceiver architectures utilizing various self-interference suppression techniques have enabled simultaneous transmission and reception at the same frequency. This full-duplex wireless offers the potential for a doubling of spectral efficiency; however, the requirement for high transmit-to-receive isolation presents formidable challenges for the...

There is now significant interest in the use of signal cancellation based architectures in an attempt to replace frequency domain filtering within the duplexing function for next generation wireless transceivers. This approach can potentially eliminate the need for band specific filters, which inhibits global operation of LTE handsets due to the di...

A key issue impacting the transmit to receive (TX-RX) isolation in Electrical Balance (EB) duplexers is dynamic matching of the antenna impedance by the balancing network. Circuit simulations including embedded antenna measurements have been used to investigate the variation in TX-RX isolation due to device motion, and to study the effect of the op...

Electrical balance duplexing enables simultaneous transmit and receive from a single antenna; however, the transmit-to-receive isolation depends on the ability of the balancing algorithm to determine the correct balancing impedance. A novel balancing algorithm based on in situ characterization of the duplexer self-interference channel is proposed....

This paper investigates electrical balance (EB) in hybrid junctions as a method of achieving transmitter-receiver isolation in single antenna full duplex wireless systems. A novel technique for maximizing isolation in EB duplexers is presented, and we show that the maximum achievable isolation is proportional to the variance of the antenna reflecti...

A key issue impacting the transmit to receive (TX-RX) isolation in Electrical Balance (EB) Duplexers is dynamic matching of the antenna impedance by the balancing network. Circuit simulations including embedded antenna measurements have been used to investigate the variation in TX-RX isolation due to interaction with the user and the local environm...

This paper introduces the ETSI Project on Broadband Radio Access Networks (EP-BRAN). BRAN systems will be used for local-area applications with limited mobility (HIPERLAN/2); fixed access with area coverage in urban and rural areas (HIPERACCESS); and short-range high-speed point-to-point links (HIPERLINK). They will support transport of either IP o...

This paper introduces the ETSI Project on Broadband Radio Access Networks (EP-BRAN). BRAN systems will be used for local area applications with limited mobility (HIPERLAN/2); fixed access with area coverage in urban and rural areas (HIPERACCESS); and short range high-speed point-to-point links (HIPERLINK). They will support transport of either IP o...

This paper discusses the general background to providing fixed “ordinary” telephone service by radio and attempts to identify the key technological issues. Finally the principle types of systems being used and developed are reviewed briefly. Propagation issues for fixed access networks are different from mobile, and in particular the use of externa...

An activity has been set up to develop a public standard for trunked radio and mobile data systems. The standards being developed are generically known as TETRA, standing for trans-European trunked radio. The ETSI is responsible for defining the TETRA standard. TETRA is really a family of standards. One branch of the family is a set of radio and ne...

The author looks back over expectations from the 1980s, and concludes that design engineers should aim at diversity of solutions, look beyond present-day fixed network standards, allow for band-sharing by systems with different service characteristics, and avoid the pursuit of integration and complexity for their own sake. Simple, limited and speci...

Six months after its commercial launch, the UK's largest public mobile data network is accessible to approximately 70 per cent of the UK population from over 150 radio base stations. Communications protocols, radio module, and application development tools for the system have been made available to application and terminal developers by the network...

A novel mobile data technology designed to support low-cost, hand-portable wireless data terminals is reviewed. The end-to-end service, the radio protocol, and the fixed network architecture are described. The radio protocol incorporates specific features to simplify hardware design, and the fixed network architecture provides for economical rollou...

Packet data services will be a vital component of a future digital trunked radio system. The air interface needed for mobile packet data will be very different from one optimised for speech. The author describes a new air-interface for packet data, which includes features specifically incorporated to enable low-cost hand-portable terminals to be ma...

Describes a phase-locked synthesiser using a combination of a novel low-frequency switched loop filter and an adaptive digital controller, which is capable of very fast frequency switching in no more space and consuming little more current than a conventional modern non-switching UHF frequency synthesiser. The loop filter permits rapid frequency sw...

This paper gives direct design formulas for asymmetric bandpass channel diplexers, which allow rapid design of diplexers using narrow-band direct-coupled resonator filters. Computed results for a prototype diplexer are given, and results are presented for a 5.8-GHz asymmetric waveguide diplexer, which demonstrate the high performance possible using...

The letter gives simple, direct formulas for the design single-sideband crystal `ladder¿ filters. The resulting designs are easily realisable by using only crystals and capacitors.

The letter proposes a new active quadrature phase-shift network, which belongs to Gingell's `symmetrical polyphase networks¿. The new network is an active ladder simulation of a suitably transformed lowpass prototype, and should have low-sensitivity properties.