Archive for April, 2010

New array synthesis tool in Antenna Magus 2.0 – very handy

Thursday, April 15th, 2010

Before I worked with the new array synthesis tool in Antenna Magus I had little experience in array design. I previously did some design and simulation work on a couple of cellular base station antennas using linear dipole and planar array configurations. Once I had to reverse engineer a planar array to reproduce the far field for EMI simulations. I wouldn’t have rated myself as very experienced array designer but after working with the new array synthesis tool I probably know 10 times more about arrays than I used to. And I’m trying not to sound too biased but it is just so easy to use and to experiment with lots of different design combinations: changing physical shape, element patterns, spacing, excitation tapers and view all the beautiful 3D patterns.

Here are a couple of different array designs I created after playing with the array tool for less than an hour. Click on the image to enlarge.

A few examples of arrays designed in Antenna Magus

A few examples of arrays designed in Antenna Magus

Author: Robert Kellerman

Announcement: Antenna Magus 2.0 released!

Wednesday, April 14th, 2010

To all our blog subscribers and those of you who might not be aware, we are proud to announce the second major release of Antenna Magus, Version 2.0. There are now 113 antennas in the database (almost double since 1.0), a new Array synthesis tool, report and data exporting, estimation speedups, support for a new simulation tool (CHAMP), more FEKO and CST MWS model options and major rework on the User interface (UI). This calls for a celebration! Read more bout Version 2.0 in Newsletter 2.0. You can also download the official press release here.

Antenna Magus 2.0 released!

Antenna Magus 2.0 released!

Author: Robert Kellerman

Story: How we added the Array synthesis tool in Antenna Magus (part1)

Friday, April 9th, 2010

I’m currently reading a brilliant book called Sketching the User Experience (by Bill Buxton). It contains this quote: “The things we have to know before we do something, we learn by doing it.” This is certainly true of our experience designing the Array Synthesis Tool.

Sometime in early in 2009, we all sat around the table and decided that we would be including an array calculator in Magus, because people kept on asking us: Can Magus do arrays? So it seemed like a feature that a lot of people really needed.

But what does that mean? When people ask whether Magus does arrays, what exactly is it supposed to do?

To find out, we interviewed people at the coffee machine, over lunch and more formally in the boardroom. We asked questions like: What are common arrays? Why would you want one? How could Magus help you? If we told you that Magus now included an array calculator, what do you think it would do? Where do you start when you design an array?

Everyone had different answers. Nobody could tell us what they wanted specifically, but at least we could form an idea of the kinds of things that engineers thought about when thinking of arrays.

Magus had always included some basic arrays as antennas like the LPDA, the Yagi, little 2-by-2 patch arrays and later on the slotted waveguide array and our beloved braairooster antenna. But of course, these antennas have specific shapes and parameters.

Array antennas in the Magus database

Array antennas in the Magus database

An array calculator, on the other hand, would have to allow you to specify (almost) any number of radiators in different layouts and then tell you what the overall performance is.

With our first design we started off with the following two premises:

  • anything is possible and
  • an array is a bunch of antennas

To design an array, therefore, you first need to know what your elemental antenna looks like. After that you can decide how many you want and how they should be laid out.

In many ways, arrays are just like antennas. Hence we thought it would be great to incorporate the array design workflow into the existing antenna design workflow, in other words: make arrays work just like antennas.

The user would design an elemental antenna, like a patch or a dipole. He could then choose to make an array of it, either by specifying the number of elements in the x- and y-directions or allowing Magus to tell him the number of elements needed, their positions and their excitations.

The first prototype (shown in the image below) was drawn up in Balsamiq and put in front of five users. In the next blog I will write on what the usability tests told us but have a look at the prototype so long and write down (or comment) what you thought about it. Click on the image below to enlarge.

Array tool: Prototype 1 (click to enlarge)

Array tool: Prototype 1 (click to enlarge)

Author: Carien Fouch

New Coffee espresso antenna

Thursday, April 1st, 2010
New coffee espresso antenna

New coffee espresso antenna

Who would ever imagine ground coffee could make an excellent dielectric? We recently did some research and experimented with different, cheaper dielectric materials.? One of our engineers suggested that we should investigate ground coffee. We originally thought it was a ridiculous idea but after some research on the electrical properties of coffee, we did a few simulations and surprisingly found that a standard double espresso group packed with ground coffee makes an excellent cavity and dielectric for a circular patch antenna in the 3.5 to 4.5 GHz range. The image above is a photo of the new Circular coffee espresso antenna. Note how conveniently the cable fits through one of the spouts.

We have been experimenting with different types of coffees and so far it seems like Arabica coffees with a lot of flavor (like the ones mentioned in my previous roasting coffee blog) give the best performance. The image below shows the new coffee antenna with a typical gain pattern at 4 GHz.

Look out for the new Coffee espresso antenna soon to be included in the Antenna Magus database!

Coffee antenna gain pattern

Coffee antenna gain pattern

Author: Robert Kellerman