With High-Speed Requirements, MM-Wave Bands Have Appeal

Several stories in this week's newsletter highlight products working at wireless frequencies somewhat higher than the "microwave-oven" range of Bluetooth and ZigBee products. In fact, one of them, a transceiver subsystem from Ducommun Technologies, mmakes use of the spectrum from 71 to 86 GHz to provide "add-on" high-speed Internet access with rates to 10 Gb/s for wireless local area networks (WLANs). At one time, such frequencies ran in the realm of either astronomy or military applications, but not for consideration in commercial terrestrial communications links. Our hunger for high-speed wireless access, with the capability to download large files and perform video streaming, is making network planners and service providers rethink the use of millimeter-wave frequencies.

Given the rapid consumption of lower-frequency bands (consider the crowding taking place in the 2.5-GHz band with Bluetooth and WiMAX), the availability of millimeter-wave spectrum would make perfect sense for network planners, except for the one small detail: the high cost of millimeter-wave components. The precision machining of passive components and the extremely fine line widths of integrated circuits still makes these components and devices fairly low-yield prospects for any manufacturer, forcing them to charge a premium for the products. Of course, suppliers of millimeter-wave components have never had the lure of large-volume markets as an incentive to find ways to lower the costs of their products. As the quest for more bandwidth continues, the days ahead should prove to be very interesting.