One Dimensional Leaky-Wave Antennas with Continuous Scan of Radiating Beam

Leaky-wave antennas (LWAs) have the ability to scan beam with frequency. However, the major limitation faced by most of the LWAs, particularly uniform LWAs, is their inability to scan beam through broadside. A method to achieve a continuous beam scan from backward to forward is discussed here. A substrate-integrated waveguide (SIW)-based structure is used for the study. The SIW-based LWA with only horizontal (longitudinal) slots is unable to scan the beam through the broadside due to an open stopband (OSB). The OSB is closed by using additional vertical (transverse) slots and groups of shorting vias. The simulated results show that the LWA can scan beam continuously from -47 to +27when frequency sweeps from 8.75 to 13 GHz

Controlling the beam scanning limits of a microstrip leaky-wave antenna

An electronically controlled half-width microstrip leaky-wave antenna (HW-MLWA) that can scan the main beam at a fixed frequency is presented. A technique is described to change the upper and lower limits of the beam direction without changing the scanning range itself. By varying the reactance profile at the free edge, the main beam of the proposed antenna can scan a range of 23° in discrete steps. There are 30 stubs positioned at the free edge of the antenna that gives the freedom to the designer to change the upper and lower scanning limits of the antenna without changing the scanning range itself. © 2013 IEEE

Modelling PIN diode switches in reconfigurable leaky-wave antenna design

The effect of PIN diodes on the performance of a reconfigurable leaky-wave antenna (LWA) is studied. The PIN diode is modelled in three different ways. It is shown that the non-ideal behaviour of the PIN diodes changes the predicted return loss and radiation characteristics of the antenna compared to ideal switches. © 2013 IEEE

Improving Cross-Band Isolation in Multi-Band Antennas

The evolution of mobile communication technologies from GSM to 5G has demanded Base Station Antennas (BSA) to support multiple frequency bands. Some very common bands include 617 MHz-960 MHz (Low Band), 1695 MHz-2180 MHz (High Band 1), 2490 MHz-2690 MHz (High Band 2) and 3300 MHz - 3800 MHz (High Band 3). The current BSA designs cater for multiple bands in a single antenna system as it provides greater cost saving in terms of utilized real estate. However, this requires multiband antenna arrays sharing a single aperture. Designing such antennas can present many challenges such as poor cross band isolation, degradation to patterns in terms of increased squint, variation in beamwidth, high side lobes etc.