Millimeter-Wave Integrated Side-Fire Leaky-Wave Antenna and its Application as a Spectrum Analyzer

TL;DR

This paper introduces a novel, integrated, shielded spectrum analyzer operating around 60 GHz using a side-fire Leaky-Wave Antenna design, demonstrating broadside radiation, beam focusing, and a 1 GHz resolution in a compact form.

Contribution

It presents a new side-fire LWA configuration for integrated spectrum analysis, including design, modeling, and experimental validation at millimeter-wave frequencies.

Findings

Operates effectively between 59-66 GHz with 1 GHz resolution.

Achieves beam focusing in the near-field for compactness.

Demonstrates broadside radiation and shielding capabilities.

Abstract

An analog, low-profile and shielded spectrum analyzer is proposed for operation at mm-wave frequencies around the 60 GHz band based on a novel side-fire Leaky-Wave Antenna (LWA) configuration. The proposed side-fire periodic LWA is systematically developed from a conventional 3-port waveguide T-junction which is modified to a LWA unit cell with an internal matching mechanism to suppress the stop-band and enable broadside radiation based on unit cell symmetry considerations. The resulting periodic side-fire antenna radiates in the plane of the antenna, whereby the leakage power be either be allowed to radiate in free-space or kept confined inside a PPW structure. The proposed side-fire structure thus can be completely shielded useful as an analog broadband spectrum analyzer using Substrate Integrated Waveguide (SIW) Technology. Furthermore, a convex side-fire antenna is demonstrated to focus the radiated beams in the near-field of the structure to make the entire system compact. The integrated spectrum analyzer is experimentally demonstrated between 59 GHz - 66 GHz providing 1 GHz frequency resolution. Furthermore, a simple mathematical model consisting of array of line sources is proposed to efficiently model the beam-scanning characteristics of the curved side-fire LWA in the near-field of the structure.