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A compact rectangular monopole with an equal-width ground plane is presented. This novel structural configuration could significantly improve its radiation performance and decrease its size. The feeding structure composed of a trident-shaped strip and a tapered impedance transformer is presented and discussed. Its impedance bandwidth, defined by measured VSWR less than 2, is from 2.75 to 16.2 GHz with a ratio of about 5.9:1. Both numerical and experimental results show that the proposed monopole antenna has stably omni-directional H-plane radiation patterns with low cross-polarization level within its impedance bandwidth. This novel monopole antenna has ultrawide impedance bandwidth, very compact size (30 mm*8 mm), low fabrication lost, and omni-directional H-plane radiation patterns, which are suitable for various broadband applications. Index Terms--Equal-width ground, omni-directional, printed monopole, ultrawideband (UWB).

Since 21st century, the test service for digital TV terrestrial broadcasting has been successively carried out in some Chinese big cities, and bus commuters can watch TV programs while traveling in the signal-covered regions. When the digital mobile TV coverage is planned, the level of radio noise in environments is of considerable concern to designers. In this paper the results of average noise power of a digital TV channel in a UHF band on public transportation courses are introduced. Not only the noise factors but also the K times variance deviation of the upper decile of noise factors under three typical communication environments has been obtained through the analysis of nonlinear regression of cumulative distribution functions on the test results. Through the trials of mobile reception of digital television, two coverage plans have been compared; The results show that the coverage effect for the model based on interference statistical distributions is higher than the one based on AWGN noise. Index Terms--Digital TV, land mobile radio interference, radio broadcasting, radio noise and data models, UHF measurements.

An investigation is described of the pulse preserving capabilities of printed circular disk monopole antennas with rectangular, curved, and hexagonal grounds in the scope of correlation factors. Detailed study on parameters is presented. Both numerical and experimental results show that a circular disk monopole with properly-designed curved or hexagonal grounds would have better pulse preserving performance than the identical monopole with rectangular ground. The improvement of the correlation factors in the x-y plane introduced by the curved and hexagonal grounds is about 6.4% and 8.1% on average, respectively. This optimization process won't bring any size or cost increase to the printed monopole antennas, and the improvement of pulse preserving capabilities is quite discernible, which appears to be a significant improvement over printed monopole antennas. Index Terms--Correlation factor, disk monopole, pulse preserving capabilities, ultrawideband (UWB).

For a concentric array radial line slot antenna with a boresite beam, a rotating mode should be excited. A planar feeding circuit exciting a rotating mode in a parallel-plate waveguide is proposed in this paper. The structure consists of a coplanar waveguide, ring slot, and cavity, which is planar and suitable for integrating and minimizing even in a millimeter-wave band. The experimental results agree well with the simulation. Index Terms--Cavity, concentric array radial line slot antenna (CA-RLSA), coplanar waveguide (CPW), feeding circuit, planar, ring slot.

A planar element-waveguide mixture structure antenna is analyzed using a spectral domain approach and eigen-function technique. The difficulty to satisfy the boundary conditions on the side walls of cavities and waveguides in spectral domain is overcome. The confidence in our method is strengthened further by the convergence of mode series and the fine agreement between theoretical and experimental results. Index Terms - Antenna theory.

E-shape patch antenna is proposed for millimeter wave frequencies. Using this E-shape structure, the patch antenna is designed for wideband operation at about 31.6-40 GHz for millimeter wave communication. Simulated and measured results for main parameters such as return loss, impedance bandwidth, radiation patterns and gains are also discussed herein. The study shows that modeling of such antennas, with simplicity in designing and feeding, can well meet millimeter-wave wireless communication. Index Terms--Circular polarization, E-shape, millimeter-wave, patch, wideband.