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The Internet of Things (IOT) is a revolutionary communication technology which enables numerous heterogeneous objects to be inter-connected. In such a wireless system, interference management between the operating devices is an important challenge. Cognitive Radio (CR) seems to be a promising enabler transmission technology for the 5G-IOT system. The “sense-and-adapt” smart transmission strategy in CR…

IEEE 802.11 WLAN indoor networks face major inherent and environmental issues such as interference, noise, and obstacles. At the same time, they must provide a maximal service performance in highly changing radio environments and conformance to various applications’ requirements. For this purpose, they require a solid design approach that considers both inputs from the radio…

Frequency diverse array (FDA) employs a small frequency increment across its array elements to provide range, angle and time dependent beampattern. In most radar systems, FDA with linear frequency offsets have been employed. But, its transmit beampattern is coupled in range and angle dimensions, which may degrade the output signal-to-interference-plus-noise ratio performance. Note that nonlinear…

In this paper we present a measurement system that is able to evaluate radar algorithms for vital signs sensing applications. For such medical applications, it is crucial to develop robust and reliable algorithms that are tested in a laboratory environment. The presented measurement system generates reproducible vital sign micro movement and dynamic clutter using loudspeakers…

This article presents a comprehensive review on the feasibility and challenges of millimeter wave in emerging fifth generation (5G) mobile communication. 5G, a multi-gigabit wireless network is the next generation wireless communication network. The mmWave cellular system which operates in the 30-300 GHz band has been proposed for use as the propagation channel. Its large…

This paper presents a resource-friendly dynamic digital beamformer for a portable ultrasound imaging system based on a single field-programmable gate array (FPGA). The core of the ultrasound imaging system is a 128- channel receive beamformer with fully dynamic focusing embedded in a single FPGA chip, which operates at a frequency of 40 MHz. The Rx…

In this paper an efficient feedback quantization technic for beamforming in MIMO systems is presented. The proposed technic named time domain quantization TD-Q is based on the feedback of time domain parameters necessary for the reproduction of the beamforming matrix at the transmitter. This TD-Q presents the same performance than the conventional Givens rotation quantization…

Frequency diverse array (FDA) antenna employs a small frequency increment, as compared with the carrier frequency, across antenna array elements. The use of a frequency increment generates an array factor that is dependent on angle, time, and the range and this yields a range and angle dependent beampattern. In this paper, a transmit array beamforming…