This site uses cookies to store information on your computer. Some of these cookies are essential to make this site work and others help us to gain insight into how it is being used.
More
These cookies are set when you submit a form, login or interact with the site by doing something that goes beyond clicking some simple links. We also use some non-essential cookies to anonymously track visitors or enhance your experience of this site. If you're not happy with this, we won't set these cookies but some nice features on the site may be unavailable. To control third party cookies, you can also adjust your browser settings. If you wish to view any policies or terms of usage that you cannot find on this website, please contact us. You can change your mind and opt-out at any time by clicking the ✻ icon above.
I consent to cookies
I don't consent to cookies
Armms RF and Microwave Society

Conferences

Next Conference:

Monday 27th April to Tuesday 28th April 2020 at Double Tree by Hilton Oxford Belfry,

CANCELLED: The social distancing rules put in place to combat the Covid-19 pandemic means that the April 2020 ARMMS meeting has had to be cancelled. All delegates who have already booked will be refunded in full.

Our next meeting will take place in April 2021.

Young Engineer Sponsorship: The ARMMS RF & Microwave Society provides sponsorship for young engineers (28 or below) who have had papers accepted for presentation at each meeting. Sponsorship is £200 cash plus free attendance (including conference dinner and overnight accommodation). Potential candidates should identify themselves as eligible at time of submission and state their date of birth. This offer is limited to a maximum of 2 places per meeting.

Best Paper Award: The Steve Evans-Pughe prize is awarded to the best presenter at each meeting. The award is £200 for the best paper and £50 for the runner-up. The prize is sponsored by NI.

If you are interested in submitting a paper for presentation at this conference, please contact the technical coordinator (details below). Papers currently listed below are those already accepted. The deadline for submissions is 16th of March 2020. For exhibition enquiries please email exhibition@armms.org, for all other enquiries please email enquiries@armms.org

VENUE

Double Tree by Hilton Oxford Belfry
Thame
OX9 2JW

Webhttps://doubletree3.hilton.com/en/index.html

PROGRAMME CO-ORDINATOR

Malcolm Edwards
Cadence

Tel+44 (0)7712 556430
Emailmedwards@cadence.com

PAPERS

Active Load Pull System with DPD and ET Capabilities for Communication Systems PA Design

Dr. Dragan Gecan
Mesuro Focus

This paper presents an active load-pull (LP) measurement system with modulated impedance synthesis with simultaneous operation of digital predistortion (DPD) and envelope tracking (ET) capabilities. The system performance is demonstrated on a 10 W GaN HEMT device from Wolfspeed biased in Class AB. The LP measurements are conducted with a constant drain supply voltage and with applied ET shaping functions, using 10 MHz LTE signal at 2 GHz centre frequency. Both cases are measured with and without DPD applied. In the static drain supply case it is shown that with applied DPD the ACPR contours are aligning with the maximum output power contours resulting in linearized ACPR values meeting and exceeding 3GPP linearity specifications (-45dBc). In the case with applied ET it is shown that the PAE can be improved by 3 percentage points by reoptimizing the load impedance from the static supply case. In addition to this, DPD is applied to the ET PA to improve linearity in this efficiency enhanced state of operation. Furthermore, in the case of an PA LP measurement the ACPR contours are indicating a VSWR circle covering an area where the linearity specification is satisfied. Since antennas typically have VSWRs greater than 1.5 this system performance check can de-risk the final PA design by emulating system level environments. Such a measurement system can be a valuable tool for matching circuit optimisation of PAs with applied DPD and/or ET techniques and de-risk an amplifier designs at an early stage of the design process.


Design of Planar Sensor for Material Characterization using Minkowski Fractal Technique

Giorgos Savvides
University of Leeds

This paper presents on a miniaturized planar sensor for characterizing relative permittivity of materials. The proposed planar sensor design is based on a near-field transmission-line measurement technique implemented by a modified complementary square ring resonator (CSRR). The 1st and 2nd iterations of Minkowski fractal pattern are applied to minimize the size of the CSRR, while still achieving an operating frequency at 2 GHz. By loading a material under test (MUT) on top of the CSRR, the relative permittivity of material can be extracted based on transmitted electromagnetic-wave energy interacting, which is changed depending on the dielectric properties of the material, between the MUT and the CSRR. Five microwave laminates, e.g. RT/duroid 4003, 6002, 6006, DiClad 880, and FR-4, are measured and performed to generate the relative permittivity extraction model. The extracted relative permittivity results from the developed numerical model show an agreement of higher than 94% as compared with the value of microwave laminates, which is identified on datasheet. The size reduction of the modified CSRR by using the 1st and 2nd iterations of Minkowski fractal technique when compared with a square ring resonator (0th iteration) are 31% and 45%, respectively, resulting in reducing the sample size of dielectric measurement. The proposed planar sensor also offers other advantages, such as the ease of design, low-cost, and miniaturization.


Directional Modulation Using Phased Arrays - Proof of Concept and Strategy for mmWave Implementation

Ben Goode
Cambridge Consultants

Directional Modulation (DM) is a promising secure physical layer modulation technique able to maintain a low bit error rate (BER) transmission in only an intended target direction, whilst scrambling data in other directions. This is achieved by “on-the-fly” symbol based modulation of a common carrier using the individual phase shifters on a phased array antenna. Furthermore, if data transmitted in this way is encrypted then the channel has two layers of security, having obvious application to defence and other secure communication markets.

Here, we present a proof of concept experiment to validate the theoretical background and then go on to explore how DM may potentially be implemented using the multi-channel mmWave beamformer RFICs currently being released for LEO SATCOM and 5G applications.


Full Duplex Communications, RF Front End

Gavin Watkins
Toshiba Research Europe Limited

Full Duplex is the simultaneous transmission and reception on the same frequency channel at the same time. It has been touted by academia and start-ups as a means of doubling the capacity of wireless networks. Although simple in theory, the practice is significantly harder due to the large difference between transmit and receive power. To enable accurate reception of a wanted signal, the transmitter self-interference must often be cancelled in the receive path by 100 dB. This is achieved by injecting a replica of the transmitted signal must into the receiver chain with the exact same magnitude but in antiphase to the self-interference. This paper will look at these requirements and discuss two different implementations for a single (shared) antenna frontend.


RF System Design - Supplementing the Design Flow

Lord Ali
Surface Technology Intl. Ltd

A simple spreadsheet or piece of paper, are quite often the tool of choice for performing engineering design calculations. But these are by no means the only tool. Modern RF systems demand many specifications which can make any spreadsheet or paper calculation unwieldly. RF design software can be used to readily help in some scenarios, whether freely available or paid. This paper will discuss and introduce a method used by the R&D team at STIL, to enable the design of an RF transmitter system and eventually how some of the system components can then be designed. The software’s (Keysight Pathwave ADS) strengths will be used to aid in a key area of the design process.


SIWAF for Space and Defence applications

Stephen Aubrey
Cobham

SIWAF is a novel, innovative and patented technology from Cobham Microwave France. This technology enables a wide range of differentiated, high performance RF and Microwave circuits and sub-systems.


Software Defined Transmitter for testing Load Pull due to antenna mutual coupling In Phased Arrays and MIMO

Roger Green
University of Bristol

This paper details a complete design of a software defined transmitter (SDT). The architecture enables identical transmitters to be paralleled up and used to drive an antenna array synchronously.

Each SDT feeds its antenna with a signal that is accurately phased aligned with the other signal that are feeding the rest of the array antennas. The SDTs have the ability to change the amplitude and phase of each individual carrier signal as well as switching the RF on/off.

A comprehensive graphical user interface is used to control single channels individually or the whole system ie: all channels simultaneously.

Measured radiation patterns of the array in an anechoic chamber are performed and evidence of antenna mutual coupling.


System Level Modelling Accuracy and the Impact on Active Antenna Radiation

Wissam Saab
AMCAD Engineering

The increased risk of impairments resulting from ever increasing architecture complexity of novel communication systems requires high circuit model quality. Accurate simulation of the RF chain is needed in order the reduce the cost of prototyping and optimizing the design performance. In the chain, the nonlinear Power Amplifier (PA) is one of the most challenging circuit to model. Circuit-level simulation and look-up table models are not suitable anymore for optimized subsystem design and accurate system analysis.

The PA description must accurately reproduce the nonlinearities and memory effects, present at different time scales.  The management of these parasitic effects is quite challenging with increasing modulation bandwidths and Antenna arrays size. Therefore, innovative modelling methodologies associated with advanced measurement techniques are now mandatory to speed-up the design cycle.

This paper will address the impact of system model accuracy on the prediction of the radiation pattern for beamforming active antenna.


The Design and Simulation of a GaN Solid State Power Amplifier Operating Over 6 to 18 GHz with an Output Power of 70 Watt

Avtar Virdee
Microwave Technology Ltd

A wideband high power microwave power amplifier is an essential component in many RF applications, such as electronic warfare (EW) systems, security communications and RF jamming. The conventional traveling wave tube amplifier (TWTA) has been most commonly used to achieve output power over wide bandwidths. However, the emergence of GaN-HEMT devices raises the prospect of replacing bulky TWTAs with compact high power solid state power amplifiers. GaN-HEMT devices are high-electron-mobility transistors and have the inherent advantages of high breakdown voltage, high current density, high saturation velocity resulting from their wide band gap properties and superior reliability performance compared with the TWTAs. The paper discusses the design and simulation of a GaN-HEMT based high power solid state power amplifier operating over 6 to 18 GHz. The solid state power amplifier combines a number of GaN MMIC with a low loss broadband power combiner in order to achieve an output power 70 watts. The design of the amplifier is based on using bare die devices and microwave integrated circuit technology that enables in realizing a highly compact design solution.



EXHIBITION

Companies booking two or more delegate places are able to take part in the commercial exhibition that accompanies the conference. Please note: there is a maximum of 20 exhibition tables at each meeting, these are offered on a first come basis. Booking two delegate places does not guarantee an exhibition space, please email exhibition@armms.org to check availability and reserve and exhibition space.


SPONSORSHIP

The society would like to thank RFMW and Ampleon for sponsoring the November 2019 meeting:

 


CALL FOR PAPERS

Contributions are invited with an emphasis on RF and microwave design, research, testing and associated subjects. An oral presentation will be made at the meeting and a written paper will be required for publication in the society digest, which is distributed to delegates at the meeting. Prospective speakers are requested to submit a title and a short abstract to the technical coordinator (see above) as soon as possible.

Click here to view our Guidelines for Authors
Click here to view our Publication Release Form

Receive future programme details