Wraparound Antenna Research Articles

GPS Signal Tracking on a Multi-antenna Mounted Spinning Vehicle by Compensating for the Spin Effects

To receive GPS satellite signals continuously on a spinning vehicle, an omnidirectional wraparound antenna or multiple patch antennas are needed. If multiple patch antennas are used, as spin effects, Doppler frequency is induced by the rotation of the antennas, and carrier phase changes abruptly when the receiving antennas are changed by the antenna’s beamwidth. Because the spin effects make it difficult for a conventional GPS receiver to track the signals, this paper proposes an algorithm to compensate for the spin effects on a GPS receiver. First, roll angles are estimated by a GPS roll-angle determination algorithm and then the Doppler frequency and the magnitude of the phase discontinuity are calculated based on the estimated roll angles, which are used in the phase locked loop of the receiver to compensate for the spin effects. Finally, the performance of the proposed algorithm is validated by computer simulations.

Design and implement of transceiver system for hybrid rocket with coplanar wraparound antenna at 433 MHz

This study aims to implement the telematics between hybrid rockets and the ground receiving station. In order to significantly reduce the rocket weight, fibre-reinforced plastic is used for the hybrid rocket casing, on which coplanar wraparound antennas with an operating frequency of 433 MHz are designed. The antenna structure contains three coplanar printed patches, among which the middle printed patch is the primary radiator and the resonant length appears a wavelength for the metallic surface case. An RF module with high receiver sensitivity and a high-power power amplifier are included to enhance the communication coverage of hybrid rockets and the ground receiving station so that the station can effectively track the hybrid rocket. Finally, the radio wave propagation model is used for calculating the link budget such that the communication coverage between rocket transmitters and the ground receiving station can be estimated, and on-site measurement and verification are preceded.

Study of Inkjet Printing as an Ultra-Low-Cost Antenna Prototyping Method and Its Application to Conformal Wraparound Antennas for Sounding Rocket Sub-Payload

Study of Inkjet Printing as an Ultra-Low-Cost Antenna Prototyping Method and Its Application to Conformal Wraparound Antennas for Sounding Rocket Sub-Payload

Design, Development, and Fabrication of a Traveling-Wave Antenna on a Conical Surface

A novel design methodology is illustrated, along with the fabrication technique for a wrap-around antenna in the C band on a conical surface. The methodology illustrates an attempt to achieve broadband performance with a thin conformal antenna. An attempt is also made to fabricate such an antenna on the parent body by a progressive lamination process of the layers. Experimental results are shown for the antenna fabrication technique.

A conical microstrip antenna with uniform substrate

A novel conical microstrip antenna with uniform substrate is investigated. The far field radiation patterns of wraparound microstrip antennas mounted on such a structure are studied theoretically. Results for a wraparound antenna of half-wavelength in width excited by TM01 are given, which are verified accurate and efficient by the ones of wraparound cylindrical antennas when the cone angle is very small.

Annular ring microstrip antenna on a spherical body

AbstractA theoretical analysis on the radiation pattern and the radiation resistance of an annular ring microstrip antenna mounted on a spherical body using an electric surface current model is presented. The effects of the dielectric layer and the metallic sphere are rigorously taken into account by the Green's functions in the spectral domain. Results for the antenna operating in the TM01 (wraparound antenna) and TM12 modes are given. © 1994 John Wiley & Sons, Inc.

Analysis of wraparound microstrip phased array by infinite array approach

A moment method analysis of an infinite array of wraparound microstrip antennas fed with idealized current probes on a cylindrical body is presented. The integral equation is formulated through the use of periodic grounded dielectric slab Green's function. The method accounts for the blind angles and allows efficient computation of the reflection coefficient at all other angles. Illustrative results are given. >

The dyadic Green's function for the cylindrical chirostrip antenna

Using the eigenfunction expansion of dyadic Green's function in unbounded chiral medium, and the method of scattering superposition, the expressions of dyadic Green's function for the one and two—layer cylindrical chirostrip antennas are derived, when the field sources are placed in any layer of cylindrical chirostrip antenna. Also, using the method of saddle point integration, the asymptotic expression of dyadic Green's function for the wraparound chirostrip antenna is obtained. The results can be directly used to analyse the radiation characteristics of cylindrical chirostrip dipolc antenna, et al.

Patch antennas on a spherical body

The far field radiation patterns of wrap-around, circular disk and annular ring microstrip patch antennas mounted on a sphere are studied theoretically. The patches are replaced by equivalent magnetic currents based on cavity model theory. The radiation fields are then determined using the modal expansion technique in spherical co-ordinates. Results for a wraparound antenna of a half-wavelength in width, for the broadside TM11 mode of a circular disk antenna and for the TM11 and TM12 modes of an annular ring antenna are given. The accuracy of the simple theory is confirmed by a more rigorous but complicated theoretical approach based on electric surface current model.

Space wave radiation efficiency of a wraparound antenna and the effect of surface wave radiation due to the dielectric substrate truncation

A theoretical study of the problem of excitation of surface waves in wraparound microstrip antennas is presented. The surface waves are obtained by using a contour integral in the complex plane. The surface-wave energy loss in the antenna truncation region is partially radiated and interfaces with the space wave. The radiation efficiency and the effect of the dielectric substrate truncation of the antenna radiation pattern are shown as functions of antenna dimensions and for two values of substrate dielectric constants. >

Electric surface current model for the analysis of microstrip antennas on cylindrical bodies

An approach to the analysis of microstrip antennas on cylindrical bodies is presented. The printed radiator is replaced by as assumed surface current distribution, and the fields are solved taking into account the presence of the dielectric layer and the metallic cylinder. Calculation takes place in the Fourier domain. The far field, calculated asymptotically from this solution, is used to get the radiation patterns of the wraparound antenna for any dielectric and the half-wavelength patch for \epsilon_{r} = 1 .

Contribution to the understanding of pattern coverage of an open-circuited microstrip wraparound antenna acting at half-wavelength resonance

In the case of an open-circuited microstrip antenna wrapped around a conducting cylinder and acting at a half-wavelength resonance, we studied the influence on the pattern coverage of various parameters, such as the dielectric constant of the substrate and cylinder diameter related to the wavelength. Some contradictions with another recent paper appear and are explained.

Analysis of microstrip wraparound antennas using dyadic Green's functions

The radiation pattern of microstrip wraparound antennas was obtained here using a theory based on dyadic Green's functions for concentric-cylindrical layered media. The dielectric layer that is usually neglected as a first-order approximation was considered here. An asymptotic expression for the dyadic Green's function that takes into account only the space wave is first obtained. Radiation patterns for various radii, permittivities, and thicknesses of the dielectric layer of a microstrip wraparound antenna were obtained using as a source a uniform annular magnetic current obtained by means of a cavity model with conducting magnetic walls. The calculated values of the percent pattern coverage decreases as the thickness and the permittivity of the dielectric layer increase. The influence of the dielectric layer is more pronounced for radiation direction near that of the axis of the cylindrical surface. It is also shown that the radiation patterns at a frequency of 2.0 GHz are not much dependent on the diameter of the antenna for values from 3 to 120 in.