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Antennas are important for digital data communication and radar applications. For various applications, special performances of antennas are required. In this paper various kinds of antenna, reflector antenna, phased array antenna, low profile antennas, and reconfigurable antennas, will be discussed for various applications.
In this paper. High performance quiet zone of CATR is designed and implemented. The size of quiet zone is 1.2m × 1.2m × 1.2m with prime feed offset 3 meters reflector. The cross-pol plane wave is −60 dB at boresight beam direction. The operating frequency of this CATR is from 10 GHz to 40 GHz. The power budget of CATR is analyzed for low cross-pol antenna measurement. Both results of simulation and...
Antennas are important for digital data communication and radar applications. For various applications, special performances of antennas are required. In this paper various kinds of antenna, reflector antenna, phased array antenna, low profile antennas, and reconfigurable antennas, will be discussed for various applications.
Microwave imaging (MWI) is a promising imaging modality for breast tumor detection. One challenge faced by the ultra-wideband (UWB) radar-based breast cancer detection is the estimation of clutter-plus-noise covariance matrix. To render a more accurate covariance matrix estimate when the number of samples is not large, this paper presents a new covariance matrix estimate using the shrinkage method...
In this paper the RF delay line is used as the beam-forming network to generate eight beams for giving antenna array aperture. There are eight beam patterns from the eight antenna elements in this MBA (Multiple Beams Antenna) system. The eight antenna elements are the coaxial collinear antennas with quarter wavelength above the ground plane. The beamwidth for these eight beams are changing from 10°...
The slow-wave propagation along novel 1-D electromagnetic bandgap (EBG) structures for finite-width conductor-backed coplanar waveguides is investigated. By controlling the pattern and size of the perforation and the length of EBG cell, this structure exhibits different slow-wave and stopband characteristics. A series of these cells appears as a slow-wave transmission line that can exhibit larger...
One of the most significant things to happen in recent years is the establishment of a connected world known as “The Internet of Things” (IoT). In the IoT, the data throughput with increasing number of interconnected devices and high digital data communication for data center or personnel device is the most significant technique challenges. If the data throughput (bits/s) is not large enough, it will...
The radiation pattern of a balance dipole antenna feeds with odd mode (or differential mode) transmission line is symmetry for H-plane pattern. Unfortunately, if the transmission line is a single ended or defect odd mode the radiation pattern will be vector summation of antenna itself and the unbalance transmission. Except for the distorted radiation pattern, the impedance will also be affected by...
A dual bands three elements printed sleeve dipole antenna array with beam direction at boresight direction has been developed for the application of IEEE 802.11 a/b/g. The size of sleeve dipole antenna array is 220mm in length, 8mm in width, and 0.4mm in thickness The beam direction always points at the boresight direction even if for various frequency operation.
In this paper, a monopole antenna is designed for device with size 65mm × 38.5mm×85mm at frequency at 908 MHz. Monopole antenna with various kinds of environment is also simulated and measured. The measured antenna efficiency is 17% if without environment matching. By using stub matching, the antenna overall efficiency is improved from 17% to 35%.
This paper is mainly to explore a wideband circularly polarized antenna, and the frequency bandwidth for the broadband global navigation satellite systems (GNSS) antenna from 1.2GHz to 1.6GHz. The antenna design is about a dual-polarized magneto-electric dipole antenna, and a power divider with phase shifter was mounted under the box-shaped reflector. The antenna structure is excited by two Γ-shaped...
In order to solve the lower aperture efficiency and frequency scan characteristics of the end-fed sleeve dipole array, a dual bands three elements printed sleeve dipole antenna array with beam direction at boresight direction has been developed for the application of IEEE 802.11 a/b/g. The size of sleeve dipole antenna array is 220 mm in length, 8 mm in width, and 0.4 mm in thickness. The beam direction...
A dual polarization of patch antenna array for IEEE 802.11 a/n MIMO applications are proposed and experimentally studied in this paper. The four by one patch antenna array printed on 200 mm by 70.5 mm by 0.4 mm FR4 substrate. The FR4 substrate is 2.5 mm above the metal ground plane. The patch array has two input ports for the orthogonal polarizations MIMO application. The measured efficiency and gain...
A systematic method is first proposed for numerically analyzing the nonlinear effects of a power amplifier on adaptive arrays. By using the proposed method, the bit error rate (BER) degradation caused by the nonlinear distortion of amplifiers on a nine-element adaptive antenna system (AAS) was numerically analyzed using a least mean square (LMS) adaptive algorithm. A closed form was first derived...
In RF wireless communication systems, oscillator plays the role of providing signals, therefore high stability and low phase noise oscillator is very important. This paper use the negative resistance theory of FET, let the circuit is in an unstable state. And the use of dielectric resonator (DR) as a signal source, design of the dielectric resonator oscillator (DRO) operating frequency is 10.5GHz...
Differential-signal transmission performances good noise immunity and low EMI characteristics benefiting from its symmetry architecture. While asymmetry occurs in the differential architecture due to process or other imperfect factors, these advantages forfeit and would cause more bit error rate to the communication system due to skew or mode conversion. In order to interpret the phenomenon and physical...
The motif of this paper to research analysis of cascading test fixture (Module Compliance Board Host Compliance Board and SFP+ connector) for SFP+ cable. Analysis of cascading test fixture (Module Compliance Board? Host Compliance Board and SFP+ connector) for SFP+ cable simulated by EM simulator and using vector network analyzer to validate frequency domain and time domain results. From the simulation...
This paper presents a new covariance matrix estimate based on shrinkage method for breast tumor detection application. The parameters of shrinkage covariance matrix are obtained by solving a modified semi-definite programming (SDP) convex problem based on the mean-squared error (MSE) criterion. The reconstructed covariance matrix, using the determined shrinkage parameters, is then used to replace...
Usually the design of a monopole antenna is with symmetric on a larger ground plane for higher antenna overall efficiency. Unfortunately, in many communication devices, such as Z-wave, the overall size of the device is not only limited but also the geometry of antenna is distorted. In this paper, a monopole antenna is designed for a device with size 65mm × 38.5mm × 85mm at a frequency of 908 MHz ...
Periodic impedance caused by periodic structure in transmission lines is simulated by high frequency 3-D EM simulators and RF/MMW circuit simulator. From the simulated data, the dip trend of insertion loss, which is also called as suck-out effect of high speed bulk cable, is presented. A simplified N-section LC lumped-circuit model with periodic circuit elements interpreting the periodic structure...
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