The invention relates to millimeter-wave point-to-point communication systems. A system comprises two separated millimeter-wave transceivers which provide high throughput data transmission and reception in frequency duplex mode and use high gain antennas capable of electronic scanning in some continuous angle range provided by the control module that implement control algorithms for antenna radiation pattern. Also a method based on the exploitation of scanning antennas of initial beam directions fine adjustment and subsequent beam directions tracking and readjustment when needed is proposed. The proposed system and method provide automatic recovery of failed connection in case of relay station orientation change due to influence of various external factors (wind, vibration, different intensity of heating of the bracing mountings at different time of a day and others) and can be used in backhaul systems of base station sites for mobile networks.

System and method of relay communication with electronic beam adjustment

An electronically beam steerable antenna device comprises a plurality of primary antenna elements and transmission lines, a switching network adapted to apply electric power to at least one primary antenna element, wherein the plurality of primary antenna elements and transmission lines are formed on a high frequency dielectric board and the switching network is electrically connected to the high frequency dielectric board. The electronically beam steerable antenna device according to the present invention allows for electronic beam steering in a continuous angle sector while increasing radiation efficiency. The antenna device according to the present invention may be used for providing high data rate point-to-point millimeter-wave communications in radio relay station applications.

Electronically beam steerable antenna device

We describe measurements of the angular radiation patterns from lens-coupled terahertz antennas fabricated on photoconductive substrates. These measurements were performed with a novel terahertz (THz) time-domain spectrometer in which the femtosecond optical pulses used to gate the emitter and receiver antennas were delivered by optical fiber. We used this system to perform a comparison between the two substrate-lens designs commonly used in THz time-domain spectrometers. We measured both E-plane and H-plane emission patterns for a 90° bow-tie antenna. By comparing these experimental results with simulations based on Fresnel–Kirchoff diffraction, we find that the choice of substrate-lens design is important in determining not only the directivity of the emitted beam but also the spectral bandwidth. These results emphasize the significance of this crucial component in the design of broadband THz spectrometers.

Influence of substrate-lens design in terahertz time-domain spectroscopy

In this paper, we report an integrated silicon-based active imaging chipset with a detector array in 0.13 $\mu{\hbox{m}}$ SiGe process and a CMOS-based source array operating in the 240–290 GHz range. The chipset operates at room-temperature with no external RF or optical sources, high-resistivity silicon lenses (HRSi) or waveguides or any custom fabrication options, such as high-resistivity substrates or substrate thinning. The receiver chip consists of a 2-D array of 16 pixels, measuring 2.5 mm $\times$ 2.5 mm with integrated antennas. An electromagnetic-active circuit co-design approach is carried out to ensure high-efficiency interface with detectors operating above cut-off frequencies with good impedance matching, near-optimal noise performance, while simultaneously suppressing the dominant surface-wave modes in a lensless lossy bulk silicon substrate. The array performance is characterized in the WR-3 band between 220–320 GHz. At the designed frequency of 260 GHz, the NEP of all pixels stays between 7.9 ${\hbox{pW}}/\sqrt{\hbox{Hz}}$ –8.8 ${\hbox{pW}}/\sqrt{\hbox{Hz}}$ . The imaging chipset consists of this 2D detector array chip and a CMOS-based source array chip measuring 0.8 mm $\times$ 0.8 mm. The entire system dissipates less than 180 mW of DC power, representing a truly integrated solution.

Silicon Integrated 280 GHz Imaging Chipset With 4 $\times$ 4 SiGe Receiver Array and CMOS Source

Summary form only given. A quasi-optical corrugated horn has been constructed for a W band gyro-TWA1,2 based on a cusp electron beam source3–5 with a helically corrugated interaction region6–8. The design is intended to provide an effective method to decouple the radiation and the beam so that a depressed collector energy recovery system may be used9–11. The horn converts a cylindrical TE 11 mode into a free-space TEM 00 mode over a frequency band of 84 to 104 GHz. This Gaussian mode can pass through the collector system unperturbed. This type of mode converter was chosen due to the performance advantages of greater bandwidth and continuous operation over this bandwidth. The design was optimized using a mode matching method that predicts a reflection of better than −35 dB and a Gaussian coupling efficiency of 97.8%. The prototype, which has been constructed and tested, demonstrates a close agreement with these figures

https://www.lboro.ac.uk/microsites/eese/icops2012/Program/Abstracts/ICOPS_3P-45.pdf

A high directivity broadband corrugated horn for W-band gyro-devices

In this paper the exact analysis on the waveguide junction circulator and Faraday rotator are presented in detail. The correctness of analysis is demonstrated by its successful prediction about the performance of the devices. Many calculation results are presented by comparing with the experimental results. The approaches of expanding bandwidth of devices at W band are stated.

Millimeter wave ferrite circulators and rotators

In this paper, extended hemispherical and elliptical silicon dielectric lenses are compared by means of ray tracing. It is shown that the optical focuses of two lenses are not at same position though the elliptical lens is synthesized from an extended hemispherical lens by carefully choosing a particular extension length as stated in ref[1]. It may be used to explain why the best compromise between alignment, directivity and Gaussian-coupling effciency will be obtained if the feed antenna is placed at the region between 2.2 mm and 2.4 mm of extension length (for 13.7 mm diameter lens, dielectric contant = 11.7).

Ray tracing on extended hemispherical and elliptical silicon dielectric lenses

The far-field patterns of an extended hemispherical-lens/objective-lens antenna system fed by a double-slot antenna is computed using the hybridisation of ray-tracing and diffraction techniques. The difference patterns computed for a monopulse antenna are also presented. The computation results show that this antenna has good performance. Although the double-slot antenna is used as a feed antenna, other antennas such as slot-ring or bowtie antennas can also be used. This antenna can be used in many millimetre-wave systems.

http://ieeexplore.ieee.org/iel4/2196/15462/00713335.pdf

Pattern prediction of extended hemispherical-lens/objective-lens antenna system at millimetre wavelengths

In this paper simple closed form expressions of surface wave fields for microstrip dipoles on grounded substrates are presented. The surface power, radiated power and radiation efficiency are calculated. It is shown that the radiation efficiency decreases with the increase of substrate electrical thickness. Hence new type antennas are needed to radiate millimeter wave because of the effect of the surface waves in substrate.

Surface wave fields and power in millimeter wave integrated dipole antennas

A Ka-band microstrip circulator, using ferrite with 4π M=5000 G, have been developed. By optimizing the circulator configuration, broadband n=2 Chebyshev response performance are obtained over 7 GHz bandwidth. The circulator have isolation of greater than 15 dB, and insertion loss of less than 1.0 dB.

Z. L. Sun

Papers

Millimeter wave ferrite circulators and rotators

Ray tracing on extended hemispherical and elliptical silicon dielectric lenses

Pattern prediction of extended hemispherical-lens/objective-lens antenna system at millimetre wavelengths

Surface wave fields and power in millimeter wave integrated dipole antennas

A broadband Ka-band microstrip circulator for integrated millimeter wave systems