Wideband Log-periodic Antenna Research Articles

A Novel Compact High Gain Wide-Band Log Periodic Dipole Array Antenna for Wireless Communication Systems

This paper implies a prototype for a broad-band log periodic dipole antenna (LPDA) with dimensions of 20 × 40 × 0.508 mm3 equipped with directors. The LPDA is based on Roger’s RT5880 with εr = 2.2. The 4-arms with alternative stubs constitute the LPDA, which is evenly spaced on both lines. At the substrate’s back, the 50Ω main feeder line is placed on partial ground. The directors are also incorporated and studied in a regular matrix at a predetermined distance to improve gain, further reduce side lobes, and widen the frequency band. The performance of the antenna covers a wide spectrum of millimeter waves ranging from 26 up to 44 GHz. The realized gain for the antenna is 8.97, 11.96, 13.96, and 14.29 dB at 28 GHz, 35 GHz, 38 GHz, and 43 GHz, respectively. The total gain is 14.29 dB as a peak gain. The antenna was designed and tested for 5G communication applications in autonomous vehicles, and the design cost for the antenna is low in comparison to dielectric lenses. The model exhibits symmetrical radiation patterns for the antenna range. The results of the simulations and the testing of the implemented antenna elements coincide quite well. The proposed design outperforms earlier work in this field.

WIDE-BAND LOG-PERIODIC MICROSTRIP ANTENNA WITH DEFECTED GROUND STRUCTURE FOR C-BAND APPLICATIONS

WIDE-BAND LOG-PERIODIC MICROSTRIP ANTENNA WITH DEFECTED GROUND STRUCTURE FOR C-BAND APPLICATIONS

On Conditions for Constant Radiation Characteristics for Log-Periodic Array Antennas

Wide frequency band antenna systems are required for many now and future applications, such as in radio astronomy and ultrawideband (UWB) technology. Constant radiation characteristics over a decade bandwidth are required for some of wide band applications, for example, feeds for reflector antennas in radio telescope. The log-periodic array antenna is one of the technologies for wideband antennas. In the present paper, an analysis on condition for constant radiation characteristics over wide bandwidth for a log-periodic array antenna is presented. From this condition, a guide rule for designing a wideband log-periodic array antenna is obtained. The Eleven antenna, a decade bandwidth log-periodic array antenna, is selected to illustrate the condition and verify the analysis in the paper.

InP-Based Planar-Antenna-Integrated Schottky-Barrier Diode for Millimeter- and Sub-Millimeter-Wave Detection

An InP-based Schottky-barrier diode (SBD) is monolithically integrated with a wideband log-periodic toothed antenna for detecting millimeter- and sub-millimeter-waves at frequencies of up to the terahertz (THz) range. A module with a quasi-optical collimation lens fabricated for practical use exhibits sensitivities of 1000 V/W at 300 GHz and 125 V/W at 1.2 THz with good linearity. Near-distance wireless transmission of 5 Gbit/s data with a 240 GHz carrier is also examined using the fabricated SBD module.

Photonic generation of continuous THz wave using uni-traveling-carrier photodiode

A uni-traveling-carrier photodiode (UTC-PD) is monolithically integrated with a wideband log-periodic toothed antenna for generating millimeter and submillimeter waves at frequencies of up to terahertz range. A module with a quasi-optical output port fabricated for practical use operates up to 1.5 THz and generates an output power of 2.3 /spl mu/W at 1.04 THz with good linearity. The output power level and the operation frequency are records for wideband PD modules operating at 1.55 /spl mu/m. An investigation of the operational characteristics of the UTC-PD reveals that the effective use of the electron-velocity overshoot in the junction depletion layer is important for maximizing the output power in the terahertz range.

Continuous THz-wave generation using antenna-integrated uni-travelling-carrier photodiodes

Photonic generation of continuous millimetre- and sub-millimetre waves up to the THz range using antenna-integrated uni-travelling-carrier photodiodes is described. A device integrating a wideband log-periodic antenna exhibits a maximum output power of 2.6 µW at 1.04 THz with good linearity. A module with a quasi-optical output port fabricated for practical use generates almost the same output power as the chip at around 1 THz and operates at frequencies of up to 1.5 THz. The output power level and the operation frequency are records for wideband photodiodes operating at 1.55 µm. Devices integrating resonant narrowband dipole antennae have also been fabricated and the output power increases at resonant peak frequencies confirmed. The device having a peak at 1.04 THz exhibits a maximum (detected) output power of 10.9 µW at 1.04 THz with good linearity. This output power is the highest value ever directly generated from a photodiode in the THz range, and several times higher than the maximum value reported by the low-temperature-grown GaAs photoconductive switch at around 1 THz.

A planar wideband 80-200 GHz subharmonic receiver

A wideband planar subharmonic mixer has been designed for millimeter-wave operation. The receiver consists of a back-to-back Schottky-diode pair integrated at the base of a wideband log-periodic antenna and placed on a silicon lens. The wideband planar receiver results in state-of-the art-performance at 90 GHz (and 182 GHz) with a double-sideband conversion loss and noise temperature of 6.7 dB (and 8.5 dB) and 1080 K (and 1820 K), respectively. These results are about 3 dB higher than the results for best tuned waveguide subharmonic mixers using planar diodes. The design is well suited for higher frequencies (up to 1 THz) and for the inclusion of biased back-to-back planar diodes to ease the LO power requirements. The planar subharmonic approach results in an inexpensive wideband receiver, and the design can be easily extended to receiver arrays. >

Submillimeter-wave antennas on thin membranes

Submillimeter-wave antennas have been fabricated on 1-μm thick silicon-oxynitride membranes. This approach results in better patterns than previous lens-coupled antennas, and eliminates the dielectric loss associated with the substrate lens. Measurements on a wideband log-periodic antenna at 700 GHz, 370 GHz and 167 GHz show no sidelobes and 3-dB beamwidths between 40° and 60°. A linear imaging array has similar patterns at 700 GHz. Possible applications for membrane antennas include wideband superconducting tunnel-junction receivers for radio astronomy and imaging arrays for radiometry and plasma diagnostics.

Design of a Frequency Independent Log-periodic Antenna for 500–3000 Mc/s

The paper presents the design and development of very wide band log-periodic antenna structure for the reception of electromagnetic energy over the frequency band 500–3000 Mc/s. Printed circuit technique was utilized for fabricating the structure. The antenna has a standard type of feeding system. The VSWR over the entire desired band was found to be within 2·2. The gain varied from 7 to 10 db. over an isotropic radiator. The impedance and radiation characteristics achieved are presented.