This thesis investigates the possibility to design printed circuit board (PCB) antennas with a maximum area size of 30 x 30 mm^2 at 2.4 GHz. The resulting antenna parameters are compared to those of a commercial, more costly chip antenna, i.e., Antenova A5645. The antenna parameters that were evaluated were the antenna efficiency, the return loss and the voltage standing wave ratio(VSWR). Three types of antennas were firstly selected to be designed, i.e., the patch antenna, Inverted-F antenna and Meandered Inverted-F antenna. Using basic antenna theory, general RF knowledge and through simulations performed with the dedicated software tool ADS, five antenna designs were finally selected to be manufactured. After manufacturing, the antennas were tested in a radiation chamber. At 2.4 GHz, the best simulated antenna efficiency was 78.7%, the return loss was -33.91 dB and the VSWR was 1.041. Not all these simulated values have been proven experimentally through measurements due to insufficient equipment at the moment of performing the experiments. However, the three types of antennas were evaluated in the radiation chamber for their polarization and these measurement results are very close to the equivalent simulation results.

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Telemetry propagation channel is modeled to predict PCM/FM telemetry receiving signal level at APG(Anheung Proving Ground), ADD(Agency for Defense Development). Channel model is composed of direct wave and reflected wave in sea surface, so-called 2-ray model. Our 2-ray model includes transmitting antenna radiation pattern, auto-tracking antenna radiation pattern, sea surface reflection coefficient and phase depending on incident angle. Vertical and horizontal polarized receiving signal strength is obtained from pre-calculated flight trajectory of transmitter. Calculated results are compared with measured data in real flight test. 2-ray channel model can predict almost identical receiving signal level and calculate starting point of multi-path fading effect. Using these results, receiving system can be moved to more proper position before flight test.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Lower operating budgets and reduced personnel are causing the operators of test ranges to consolidate their assets and seek ways to maximize their utilization. This paper presents the versatile approach used by the NASA Dryden Flight Test Facility located at Edwards Air Force Base to monitor, control and operate five of its diversely located telemetry systems from a central control room. It describes a new generation of multi-purpose antenna controllers which are currently being installed as part of this NASA upgrade program.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper describes a new mobile self contained telemetry station designed for field testing of air-to-ground weapons. The telemetry station makes creative use of existing equipment and incorporates a unique dual axis tracking system to provide complete coverage of most missions.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Instrumentation antennas installed on missiles and airborne targets are required to be tested and certified prior to flight. The antenna coupler is a means of certifying that the antenna is in proper working condition prior to deployment, as damage to the antennas may have occurred during transportation or installation. This coupler also provides a low cost means to evaluate and monitor the antenna throughout the various stages of design and assembly. These antennas can contain arrays for telemetry, beacon tracking, global positioning systems and flight termination. A failure by any one of these arrays could result in the loss of data or improper operation of the flight vehicle. Description of the design and function of antenna couplers will be discussed.

Adaptive array antennas use has been limited to non-commercial applications due to their high cost and hardware complexity. The implementation cost of adaptive array antennas can be kept to a minimum by using cost effective antennas, reducing the number of elements in the array and implementing efficient beamforming techniques. This thesis presents techniques for the design of adaptive array antennas which will enable their cost effective implementation in wireless communication systems. The techniques are investigated from three perspectives, namely, reconfigurable antenna design, wide scan array design and single-port beamforming technique. A novel single-feed polarisation reconfigurable antenna design is proposed in the first stage of this study. Different polarisation states, namely, linear polarisation (LP), left-hand circular polarisation (LHCP) and right-hand circular polarisation (RHCP), are achieved by perturbing the shape of the main radiating structure of the antenna. The proposed antenna exhibits good axial ratio (< 3 dB at 2.4 GHz) and has high radiation efficiency in both polarisation modes (91.5 % - LHCP and 86.9 % - RHCP). With a compact single feeding structure, the antenna is suitable for implementation in wireless communication devices. The second stage of the study presents the design procedure of wide scan adaptive array antennas with reduced number of elements. Adaptive array antennas with limited number of elements have limited scanning range, reduced angular scanning resolution and high sidelobe levels. To date, design synthesis of adaptive array antennas has been targeted on arrays with a large number of elements. This thesis presents a comprehensive analysis of adaptive array antennas with less than 10 elements. Different array configurations are analysed and various array design parameters such as number of elements, separation between elements and orientation of the elements are analysed in terms of their 3 dB scan range. The proposed array, the 3-faceted array, achieves a scanning range up to ±70°, which is higher than ±56° obtained from the Uniform Linear Array. The faceted arrays are then evaluated in the context of adaptive beamforming properties. It was shown that the 3-faceted array is suitable for adaptive array applications in wireless communication systems as it achieves the highest directivity compared to other faceted structures. The 3-faceted array is then synthesised for low sidelobe level. Phase correction together with amplitude tapering technique is applied to the 3-faceted array. The use of conventional and tuneable windowing techniques on the 3- faceted array is also analysed. The final stage of the study investigates beamforming techniques for the adaptive array antenna. In the first part, beamforming algorithms using different performance criteria, which include maximum signal-to noise-ratio (SINR), minimum (mean-square Error) MSE and power minimisation, are evaluated. In the second part, single-port beamforming techniques are explored. In previous single-port beamforming methods, the spatial information of the signals is not fully recovered and this limits the use of conventional adaptive beamforming algorithms. In this thesis, a novel signal estimation technique using pseudo-inverse function for single-port beamforming is proposed. The proposed polarisation reconfigurable antenna, the 3-faceted array antenna and the single-port beamforming technique achieve the required performance, which suggests the potential of adaptive array antennas to be deployed commercially, especially in wireless communication industry.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Multiple discrete antennas distributed around the circumference of a large missile and driven by one transmitter are sometimes used to radiate telemetry omnidirectionally. But driving discrete antennas separated by several wavelengths around the missile body with a single transmitter can result in an antenna pattern with deep nulls in the roll plane. Varying the relative signal phase or amplitude among the signals driving the antennas as well as the polarization of the antennas can be used to change the nulls in an attempt to decrease the null depth. In this paper the effects of phase, amplitude, and polarization on the roll-plane pattern are examined and measurement data presented.

To investigate the integration of a textile antenna into a woven substrate at the point of production. The antenna was to have the characteristics of a conventional fabric interms of the handle and drape.

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