A switched-beam antenna for cellular communication

Wireless communication has created a continuing demand for increased bandwidth and better quality of services. Smart antenna arrays are one of the ways to accommodate this demand which can provide numerous benefits to service provider and the customer. Switched-beam antenna was chosen for this project due to its easier implementation and lower cost compared to adaptive array. Switched-beam antenna is one of smart antenna technique which comprises a number of predefined beams. The control system switches among the beams that provide the maximum signal response. Through the investigation and study on this system, found that, the 1200 sectorization with three monopole antenna elements suited for prototype construction. The initial stage to design this system is by using MA TLAB simulation to identify the antenna characteristic and the parameters involved. The second stage is about the construction of the prototype switched-beam antenna used to measure the antenna gain and relative power level which displayed using CASSY program

Conformal switched beam antenna

A cylindrical switched beam antenna making use of Kapton film and aperture-coupling is presented. The use of four elements controlled via a high frequency switching stage is proposed. Using very simple bias circuitry, switching can be achieved to provide four-way coverage at 0°, 90°, 180° and 270°. Elements consist of an aperture-coupled patch making use of thin film technology to provide an air substrate for increased efficiency and therefore gain. Four direction beam switching is performed using only three switches integrated into the structure. Simulated results of a single element are presented, followed by measured results of the fully fabricated structur

Switched-beam antenna array design for millimeter-wave applications

The limited coverage of wireless communication at the millimeter-wave frequency band due to large free-space path loss, i.e. large signal attenuation, has been a major problem. Furthermore, shadowing and small-scale fading may reduce the received signal even more. An array of rod antennas is designed to tackle those problems by providing high gain, broad scan range, and a shaped beam. Each patch, which couples the electromagnetic wave to the rod, is fed by a coplanar waveguide (CPW) feedline. Each rod antenna demonstrates 18 dBi realized gain and 20° half power beamwidth (HPBW). Moreover, the 4 GHz bandwidth of the antenna provides high data rate for the gigabit wireless application. Furthermore, the Radio Frequency Microelectromechanical System (RF MEMS) switch is used to realize a switched antenna with a broad scan range. The design method and the characterization of the antenna are presented. The proposed antenna system is suitable for a wide range of applications, such as wireless high definition video/audio, USB and firewire replacement, Frequency Modulated Continuous Wave (FMCW) radar, and home/office backhaul application at millimeter-wave frequency

Antenna design: a crystallographical approach

The goal of this thesis was to design a switched beam antenna by applying the principles of crystallography. The main benefit of this approach is that simple design equations can be derived from crystallography and readily applied to the design of a steerable beam antenna. Before using equations from crystallography in an antenna design, the equations are first verified. One of the best known laws of crystallography, namely Bragg\u27s Law, is verified both by software simulation, and experimentally from the radiation patterns of a prototype antenna. One set of simulations used to verify Bragg\u27s Law involved varying the angles of incidence while changing the plane spacing accordingly to maintain the diffraction condition. The average deviation between the software simulation and the calculated diffracted peak location was 0.8%, confirming Bragg\u27s Law at radio frequency. A prototype antenna was designed using Bragg\u27s Law, and the peak location was verified experimentally. The antenna was designed for use at around 6 GHz. Having verified that principles from crystallography can be applied at radio frequencies, a switched beam antenna array was designed. The antenna had three possible directions: forward, and +/- 90 degrees relative to the incident beam. The side lobe level was 15.7 dB, and the half power beam width was 2 to 3 degrees

A Simple Angle of Arrival Estimation System

We propose a practical, simple and hardware friendly, yet novel and very efficient, angle of arrival (AoA) estimation system. Our intuitive, two-phases cross-correlation based system requires a switched beam antenna array with a single radio frequency chain. Our system cross correlates a reference omni-directional signal with a set of received directed signals to determine the AoA. Practicality and high efficiency of our system are demonstrated through performance and complexity comparisons with multiple signal classification algorithm.Scopu

A dual-band single-feed switched beam antenna for WLAN

This article presents the dual-band of a single patch antenna that can operate at a frequency of 2.47 to 5.04 GHz, which is available in WLANs (IEEE 802.11). The beam pattern of the antenna can be switched by changing the position of shorted-circuit points at each edge of the antenna. The advantage of the proposed antenna is that it is a simple structure which is small in size, weighs little and has an easily adjustable beam. In addition, the antenna is tested under real circumstances using the existing WLAN infrastructure. The results confirm that the signal strength can be improved when the proposed switched beam antenna is utilized

Lens based switched beam antenna for a 5G smart repeater

A 16 switched beam lens based antenna with a coverage area of ±30° in the horizontal plane and from 0 to -20° in the vertical plane has been built and tested. The intended use of the antenna is as part of a smart repeater servicing the coverage area of a 5G wireless communication system operating in the n258 band of the 5G Frequency Range 2, from 24.25 to 27.5 GHz. The antenna has been built using state-of-the-art materials and components in order to assess the performance of this antenna concept. The overall antenna losses including the feeding network are of the order of 8 dB and the realized gain in the 80% of the coverage area is above 11 dB.This work was funded in part by AEI: PID2019-107885GB-C31/AEI/10.13039/501100011033 and HUAWEI TECHNOLOGIES Italia S.r.lPeer ReviewedPostprint (author's final draft

Intruder localization wireless sensor network radar design with virtual reference tags

This research designs a WSN (Wireless Sensor Network) algorithm for human intruder localization and path detection. There are two commonly used position estimation techniques in WSN, ToA (Time of Arrival) and RSSI (Received Signal Strength Indicator). In ToA the difference between arrivals of signal is estimated and based on this information position of target is calculated. This technique produces better results but in real time the cost of nodes used increases due to synchronization requirement. On the other hand RSSI technique requires no synchronization and can be considered as most simple and low cost technique but its accuracy is very low. To increase the accuracy of RSSI this research introduces VRTs (Virtual Reference Tags). VRTs are previously used in RFID (Radio Frequency Identification) system to provide reference to the system. Four reference nodes are used such that one acts as transmitting while three as receiving nodes. These nodes are placed at the edges of surveillance area. NS2 (Network Simulator 2) is used to design the WSN. The surveillance area of system is taken as 80X80 meters. Nine scenarios are checked with varying number of VRTs mapped over surveillance area. From the results it is observed that as the number of VRT is increased, accuracy of WSN radar also increases. But in actual implementation greater number of VRT can result in greater hardware requirement in terms of processor and high speed data storage. Since the proposed WSN radar is designed for human intruder localization, the WSN accuracy is kept to 0.2 meters. In simulation for a surveillance area of 80X80 meters to locate and track human intruder with 0.2 meter accuracy, 1721 VRTs are required to be virtually mapped over surveillance area. This research also presents a proposed design of WSN which can be used in vehicles as road safety feature providing assistance to driver. The WSN consists of three receivers, one on each side and one in front and the surveillance area around the vehicle is divided into levels which determine whether it is safe for driver to move towards that side. Driver alerting method is also presented using vehicle‟s steering wheel