Bandwidth is available at higher frequencies, making millimeter-wave communications links attractive at 60 GHz and above. Unfortunately, the costs associated with manufacturing and testing hardware rises with frequency, presenting genuine challenges to the companies involved in millimeter-wave markets. Although customers have been somewhat hesitant to embrace the bands through 95 GHz licensed by the United States Federal Communications Commission (FCC), a growing demand for high-definition television (HDTV) appears to be igniting interest in these high-frequency bands. Add this to existing business from military and scientific areas, and the millimeter-wave market no longer looks like something restricted to college laboratories.
The bandwidth around 60 GHz (57 to 64 GHz) has been used for high data-rate transmissions by a number of companies, including SiBeam, Inc. and its OmniLink60 system based on a CMOS transceiver chip. Earlier this year, the firm announced its solution for high-speed 60-GHz wireless data and HDTV transmissions, the SB8110 WirelessHD/WiGig transceiver and SK8100 Development Kit.
HXI, formerly Terabeam Wireless and formerly a part of Proxim Wireless, also offers a number of 60-GHz solutions, including its GigaLink HD point-to-point link. It promises dual-channel, 1.485-Gb/s per-channel rates (2.970 Gb/s total) using bandwidth from 59 to 64 GHz and +10 dBm transmit power for a range of about 500 m.
Spacek Labs offers a wide range of millimeter-wave components, from amplifiers to oscillators, as well as subsystems. The firm's transceivers range from 18 to 110 GHz, at bandwidths of less than 1 GHz to full waveguide bands. They are twochannel, full-duplex designs with a common phase-locked local oscillator (LO) for stability. On the component side, the model FS-34-36-20 is a synthesizer designed to deliver +20 dBm from 34 to 36 GHz. It can be outfitted with WR-28 waveguide or a 2.92-mm connector. It switches in 10-kHz steps with 10-ms maximum switching speed.
Millitech, Inc., a long-time supplier of millimeter-wave products, shows that a trend to integrate multiple functions within a single package is not restricted to RF and microwave frequencies. The firm's model MIQ-28-SLNA is a millimeter-wave in-phase/quadrature (I/Q) mixer with integrated low-noise amplifier (LNA). Ideal for use in radar receivers, it has an RF range of 34 to 36 GHz and an LO range of 34 to 36.01 GHz, for an intermediate-frequency (IF) range of DC to 2 GHz.
Endwave offers discrete and integrated-circuit (IC) millimeter-wave components for microwave radios to 38 GHz as well as the newer 71-to-76-GHz and 81-to- 86-GHz allocated bands. Components include amplifiers, voltage-controlled oscillators (VCOs), and voltage-variable attenuators (VVAs).
Additional suppliers of components operating at millimeter-wave frequencies include Aerowave, Ducommun Technologies, ELVA-1, ET Industries, Farran Technology Ltd., Herley-General Microwave, Hypres, Inc., Micro Lambda Wireless, Microsemi RF Integrated Solutions, MITEQ, Narda Microwave East, Norden Millimeter, Phase Matrix, Sivers IMA, Virginia Diodes, and ZAX Millimeter Wave Corp.