Dr Timothy Pelham

Dr Timothy Pelham

Research Fellow

Blog posts

2025

Beamforming and Steering Efficiency in Phased Array Antennas

5 minute read

Published:

Comparing the performance of different antenna array designs and beamforming methods can be challenging, especially when conformal antenna arrays are also considered in the design arena. The boresight gain and half power beamwidth are often used to compare antenna arrays and antenna designs, and the ideal figures are easy to calculate for a planar aperture at a given frequency. However, this tells us little about the performance of the antenna array away from boresight, and is of limited use for conformal antenna arrays. Quite a number of years ago I came across a very useful concept called steering efficiency, and the steering efficiency product, which can be used to compare different antenna array architectures and beamforming methods, accounting for different frequencies and array sizes.

[2]: J. G. Marin and J. Hesselbarth, “Figure of Merit for Beam-Steering Antennas,” 2019 12th German Microwave Conference (GeMiC), Stuttgart, Germany, 2019, pp. 44-47, doi: 10.23919/GEMIC.2019.8698122

LyceanEM Release 0.1.0

5 minute read

Published:

I’m delighted to announce the version 0.1.0 release of LyceanEM. The support of the Net Zero Innovation Portfolio has allowed us to complete the first major release of our development roadmap. This includes :

Reset Connect North Climate Reception

2 minute read

Published:

A welcome invite from Reset Connect resulted in Professor Mark Beach and I taking the train up to Westminster with posters and a Communication Systems and Networks Laboratory banner up to Parliament. Presenting the results of my work on scalable electromagnetics for Space-based Solar Power. We were able to engage with Members of Parliament from the North of England, and discuss the potential for different technologies to address the Net Zero Climate Challenge.

2024

Modelling Microwave Power Transfer

5 minute read

Published:

A critical part of the development of LyceanEM in support of the development of Space-based Solar Power is the development of a robust and accurate model for microwave propagation. The critical issue for space-based solar power is an accurate prediction of the losses from propagation through the different layers of the atmosphere for extremely large scale microwave beams, over 1km in radius. This level of electromagnetics modelling is beyond the capability of current commercial software, and requires the development of new open-source tools to support the development of the technology.

2023

Engaging Plots with PyVista

1 minute read

Published:

An intial exploration of PyVista for interactive 3D plots, and the challenges and opportunities for interactive plots in webpages.

2022

The Power of the Sun : Workshop on Space Based Solar Power

1 minute read

Published:

I’m excited to announce “The Power of the Sun : Workshop on Space Based Solar Power”, funded by the University of Bristol, and supported by the Satellite Applications Catapult and Virtus Solis. Beyond the academic interest in the problems of modelling such large antenna arrays in orbit, I am very excited about the possibility of transforming what was a staple of science fiction, into a very real contributor to the energy mix.

Unfogging the Farfield

4 minute read

Published:

When considering antennas and antenna arrays, one of the more useful and consistent abstractions are that of the plane wave, and the related concept of the farfield. These concepts are simplifications of the expanding spherical wavefronts in the limit of large distances. The approximation states that when considering a specific direction or set of directions the spherical wavefront can be approximated as a plane wave propagating in the direction of interest.

Workshop Announcement: RF Sensing as a Service

less than 1 minute read

Published:

Workshop Announcement: RF Sensing as a Service A workshop hosted by the University of Bristol as part of my research into satellite based passive radar, in order to explore the challenges, breakthroughs and applications for space based sensor networks.

LyceanEM Examples

2 minute read

Published:

Addition of examples to the documentation for LyceanEM, found at examples. The examples cover Aperture Projection, Aperture Modelling, Array Modelling and Beamforming, and modelling physical channels in the Frequency or Time Domain.

Release of LyceanEM

1 minute read

Published:

LyceanEM, the electromagnetics software I have been developing to support my research is now open for anybody to use. If you have an interest in communications, antennas, or radar then LyceanEM can help.

2021

2020

Beamforming and Conformal Antenna Arrays

2 minute read

Published:

In order to predict the performance envelope of an array, the effects of beamforming the aperture need to be taken into account. The array is modelled using electric current sources to replicate the individual elements and "Equal Gain Combining" to form the beam efficiently in along the desired directions.

Rapid EM Modelling

1 minute read

Published:

Rapid Electromagnetics modelling for mobile platforms

Why Model?

less than 1 minute read

Published:

What’s the point of Modelling?

Introducing LyceanEM

less than 1 minute read

Published:

Welcome to the LyceanEM blog, I will add to it as I work on new ways to model electromagnetics for sensors and communications. I will update this blog with musings on the changing needs of antenna engineers in the battle for bandwidth and capability on the latest sensor and communications systems, and ways to address them.