A radio direction finding (DF) system is an antenna array and a receiver arranged in a combination to determine the azimuth angle of a distant emitter. Basically, all DF systems derive the emitter location from an initial determination of the angle-of-arrival (AOA). Radio direction finding techniques have classically been based on multiple-antenna systems employing multiple receivers. Classic t...

A novel radio channel compensation method aiming to give optimal calibration for microstrip antenna array systems is presented in this paper, realized for an actual DOA measurement antenna system using microstrip antennas to sample the electromagnetic field, operating at 4.5GHz. This new approach considers mismatch between antennas and channel RF ports, channel transmission inequalities, and al...

A large-scale fully-digital receive antenna array can provide very high-resolution direction of arrival (DOA) estimation, but resulting in a significantly high RF-chain circuit cost. Thus, a hybrid analog and digital (HAD) structure is preferred. Two phase alignment (PA) methods, HAD PA (HADPA) and hybrid digital and analog PA (HDAPA), are proposed to estimate DOA based on the parametric method...

Over the past decades there has been technological breakthrough from analog to digital. Ever since the world war and also the invention of electromagnetic radio, there has always been an urge to know from which direction the signals were arriving to the listener‟s direction finding receiver. The methodology of determining the direction of arrival (DOA) of incoming signals impinging on the unifo...

Over the past decades there has been technological breakthrough from analog to digital. Ever since the world war and also the invention of electromagnetic radio, there has always been an urge to know from which direction the signals were arriving to the listener’s direction finding receiver. The methodology of determining the direction of arrival (DOA) of incoming signals impinging on the unifo...

In this paper, a method is presented that employs portable cellular devices to perform three-dimensional localization of metallic objects from a set of time-delayed signals. These signals are observed by an array of receiving elements having arbitrary and a priori known distributions in space. Widely used solutions for direction finding are based on Time of Arrival (TOA) measurements. The measu...

We address the problem of passive eavesdroppers in multi-hop wireless networks using the technique of friendly jamming. The network is assumed to employ Decode and Forward (DF) relaying. Assuming the availability of perfect channel state information (CSI) of legitimate nodes and eavesdroppers, we consider a scheduling and power allocation (PA) problem for a multiple-source multiple-sink scenari...