The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper proposes a dual-band integrated horizontally polarized antenna composed of an alternately arranged frequency selective reflector (FSR) and a bent dipole element. The antenna is composed of a FSR backed dipole antenna designed in 3.5GHz band and it is placed in front of 2GHz band reflector backed dipole antenna. It is found that the alternate FSR configuration is suitable and there is an...
In this report, we investigate prediction accuracy of fading channels in line-of-sight (LOS) environment when using autoregressive (AR) model. We especially evaluate the accuracy of the predicted channel in LOS environment when applying the theoretical autocorrelation formula of the LOS environment to the AR model. The influence of the prediction methods on MIMO capacities is also investigated. The...
Frequency dispersive phase shifter for a multi-band base station antenna, which is capable of increasing the communication capacity by deep tilt angle in the lower frequency bands, has been proposed. In this paper, in order to enlarge the amount of phase shift of the frequency dispersive phase shifter, we first derive the equivalent circuit of the unit cell of the phase shifter. A lossless symmetrical...
This paper investigates the effectiveness of the edge folded frequency selective reflector (FSR) structure in reducing mutual influence between low and high band radiation patterns of a dual band reflector backed dipole antenna (RBDA), which employs FSR in the high band RBDA. As the results of the moment method analysis related to the half-power-beamwidth (HPBW) and the front-to-back ratio (FB) characteristics...
In our previous report, the authors realized a slender omnidirectional leaky wave antenna with a single branch using CRLH line. This paper presents measurement results of a dual branch antenna orthogonally arranged the CRLH line. The diameter of the antenna including a cover is 0.14 wavelength at 3.5 GHz, and the antenna has high isolation characteristic.
This paper analyzes the S21 characteristics of a leaky wave antenna composed of CRLH coplanar strip line by using 2-port network equivalent circuit. The left and right handed modes are considered and the comparison of the S21 characteristics between the two modes is investigated. The results show that the coupling component between the unit cells radiates in the left handed mode, on the other hand,...
This paper investigates the half-power-beam-width (HPBW) and front-to-back ratio (FB) characteristics of a corner reflector antenna employing frequency selective surface (FSS). The adjustable HPBW range is clarified by changing the corner angle of the reflector. The influence of the FSS element arrangement on the FB characteristics is also investigated. The calculation result is verified by the prototype...
A slender left-handed leaky wave omni-directional antenna, which is suitable for such small cell, has been proposed. This paper derives the equivalent circuit of the unit cell of the leaky wave omni-directional antenna and derives the intercell coupling matrix for the number of cells required.
Frequency selective reflector (FSR) is useful to actualize multi-band reflector backed dipole antennas. This paper investigates a suitable FSR element shape for the FSR backed dipole antenna forming sector radiation pattern, which is suitable for mobile base station antennas. Three element shapes, Gang Buster, Jerusalem Cross, and Square Loop are considered. Radiation patterns are calculated by the...
This paper proposes a technique that uses the small-metal width of a frequency-selective surface (FSS) element to suppress the change in beamwidth due to the undesired reflection from other FSSs. FSSs reflect low-level electromagnetic waves that are expected to pass through essentially the FSSs outside of the desired reflection bands, and generate these low level reflections from other FSSs as undesired...
In this study, we propose a novel leaky-wave omnidirectional antenna using a coplanar-strip-type composite right/left-handed (CRLH) line for application to a base station antenna used for a mobile communication system. Further, we realize an extremely slender omnidirectional antenna by adopting a polarization composite method. We also design a prototype antenna in the 3.5 GHz band and show the results...
Reflector backed dipole antenna (RBD) is a typical configuration used for mobile base station antennas because the antenna has broadband characteristics and it is easy to form dual-polarized sector radiation pattern. Recent mobile communication systems are working in multiple frequency bands from 700 MHz to 2 GHz bands, thus multi-band operation is required for the base station antenna. Several types...
We propose a new broadband folded offset fed printed dipole antenna for wireless telecommunications modules that actualizes Machine-to-Machine applications. The proposed antenna is based on the folded offset fed dipole antenna structure. We obtain the broad Voltage Standing Wave Ratio (VSWR) (≤2) bandwidth of 71.2% by adjusting the shape of the folded element. This antenna achieves operation in multiple...
This paper investigates the operation mechanism of a reflector backed dipole antenna with proximity placed loop-shaped parasitic elements (RBD-LE) by considering the current distribution of various antenna configurations. Moreover, the measurements are conducted to verify the validity of the simulation results.
We propose a new small multiband printed antenna for wireless telecommunications modules that actualizes Machine-to-Machine applications. The proposed antenna is based on our previous design comprising symmetrically arranged trapezoidal elements and rectangle strip elements. It achieves operation in quad-bands: 700 MHz, 800 MHz, 900 MHz, and 2 GHz. In the new antenna, we add new folded strip elements...
Using frequency selective reflector (FSR) in reflector backed dipole antenna (RBD) is attractive to form a multi-band antenna used for a mobile communication base station antenna especially when the antenna shares apart frequencies. This paper investigates the influence of FSR element shape on the RBD performance. In addition, a configuration example applying FSR to RBD which shares 800MHz and 4GHz...
This paper investigated the effectiveness of co-located parasitic elements for enlarging the operating bandwidth of MSA. As the results, it was confirmed that co-located parasitic element in the E-plane could obtain larger bandwidth than those co-locating in the H-plane. It was also confirmed that the E-plane arrangement was suitable for the applications such as irradiating the service area.
In this paper, reflector backed dipole antenna with loop-shaped parasitic elements is considered and S11 characteristic is investigated. As the results, it is confirmed that the length including dipole and parasitic elements along the dipole element is affected to the low frequency resonance and the loop peripheral length and the position of the parasitic element are affected to the high frequency...
This paper proposes a new small multiband printed antenna for wireless telecommunications modules that actualizes Machine to Machine applications. We reconfigure our previous antenna to cover the 700 MHz, 800 MHz, and 900 MHz bands, and add two new elements to cover the 2 GHz band. The new antenna achieves operation in quad-bands: 700 MHz, 800 MHz, 900 MHz, and 2 GHz. Frequency characteristics are...
In multi-band base station antennas, interference toward neighboring cells at low operating frequency increases since tilting angle is frequency-independent and beamwidth in the vertical plane increases as decreasing the operating frequency. This paper presents a new low-profile phase shifter which comprises non-linear frequency-dependent characteristics. The proposed phase shifter is composed of...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.