Newsletter 2019.1

Antenna Magus Version 2019.1 released!

Version 2019.1 includes 3 new antennas as well as various other extensions and improvements. This newsletter will discuss the new antennas and extensions that have been made available. For more comprehensive information on the update, please visit the full release notes.

New Antennas

The new antennas (taking the total number of devices in Antenna Magus to 341) are:

  • Series-fed 3 by 3 rectangular patch array
  • Printed Multilayer Dipole Array
  • Stacked square-ring pin-fed patch

Series-fed 3 by 3 rectangular patch array
Image of the Series-fed 3 by 3 rectangular patch array.

The array consists of a 3 x 3 series fed configuration of rectangular patches. By adjusting the excitation of these ports, the direction of the main beam (squint) as well as the sense of linear polarization – diagonal, vertical or horizontal - can be controlled.

Figure 1: Typical total gain pattern comparison of radiation pattern performance at the center frequency for different excitation methods. (a) all ports excited in phase; (b) vertical ports excited with progressive phasing; (c) horizontal ports excited with progressive phasing

When all 6 ports are excited simultaneously and in phase, a symmetrical broadside lobe in the zenith direction with low sidelobe levels and diagonal linear polarisation - as shown in figure 1(a) - is achieved.

By exciting the three vertical ports only, a vertical linear polarized radiation pattern can be achieved and the direction of the main beam steered left and right (in the Φ = 0° plane) as shown in figure 1(b). If a horizontal linear polarized radiation pattern which may be steered up and down (in the Φ = 90° plane) is required, only the three horizontal ports should be excited as shown in figure 1(c).

The operating bandwidth of this antenna configuration is approximately 1%, as illustrated by the reflection coefficient of the three vertical ports.

Typical reflection coefficient versus frequency for the vertical ports

The agile polarization and steering capabilities of this antenna makes it well suited to dual polarized narrow-band airborne synthetic aperture radar (SAR) applications.

Printed Multilayer Dipole Array
Image of the Printed Multilayer Dipole Array.

5G (Fifth Generation Wireless Communication) aims to address the increasing demand for high-bandwidth, high-data-rate communication as well as the emergence of machine-to-machine communications (M2M) as part of the continuous evolution in mobile communication. MIMO (multiple-input multiple output) technology has improved the bandwidth efficiency for wireless communications systems and will form a vital part in 5G systems for further enhancement.

The printed dipole array consists of a linear array of dipoles that - depending on the element spacing - can be steered between -60° and 60°. When designed to operate at 5G mmWave bands, the array is small enough that it is feasible for multiple arrays to be integrated in a device the size of a typical mobile phone. By independently steering the beams of these multiple arrays, highly flexible and optimal MIMO operation can be achieved for different operating environments.

Typical total gain pattern at the centre frequency with a squint angle of 0°, 10°, 30°, 40° and 50° for an 8-element array
Typical active S-parameters versus frequency for an 8-element array with a 30° squint angle
Stacked square-ring pin-fed patch
Image of the Stacked square-ring pin-fed patch.

While the simplicity and compatibility of the well-known rectangular patch antenna makes it very popular, the size and limited bandwidth often restricts its suitability for direct integration into circuit boards. The standard rectangular patch forms the basis for a number of antenna variations, typically introduced to overcome a particular shortcoming of the standard structure.

One approach to reduce the size of a patch antenna involves removing a rectangular area of metal from the patch center. While this lowers the resonant frequency, it also reduces the achievable bandwidth. This bandwidth reduction may in turn be countered by using a stacked arrangement comprising of a parasitic square-ring element mounted above an active/driven square-ring element. The parasitic element is added primarily to increase the impedance bandwidth - by introducing an additional resonance in the operating band - but also has the advantage of improving the gain of the antenna.

Typical total gain pattern at the center frequency
Typical reflection coefficient versus frequency comparison for three types of rectangular patches

Extensions

New Toolbox Calculators

A new group of Transmission Line Calculators has been added to complement the existing calculators available in Antenna Magus. This group of calculators includes some of the most commonly used transmission line calculators, namely: Microstrip Line, Coaxial Line, Coplanar Waveguide (CPW), Grounded Coplanar Waveguide, Circular Waveguide and Rectangular Waveguide. The transmission line calculators may be found on the Ribbon of the Toolbox tab.

New Transmission Line calculators

Array Operators

Various improvements have been made to the array operators. These include two new surface shapes – conical and cylindrical – which are now supported in the Conformal operators group and the automatic pre-population of Operator fields with typical/default values when any new Operator is added. Other small usability improvements include that information documents for Array Operators are now scrollable using the mouse wheel.

New Connector

The Connector library has been expanded to include two variations of the UFL connector – part of the Ultra Small Surface Mount series. This connector is especially popular in applications where space is a major concern, such as laptops, embedded systems and GPS devices. The connector offers good performance from DC to 6 GHz, with VSWR ranging from 1.3-1.5.

3D and 3D (cut) view of the UFL Jack surface mount connector
3D and 3D (cut) view of the UFL plug cable mount connector