Articles

Interesting article, but I would take exception to the characterization of GaAs as "power hungry". The use of GaAs for portable low GHz frequency devices like cell phone handsets and wireless LAN transceivers is largely because they are more power efficient (and cost effective) than Si alternatives. I don't think that would change at 60 GHz.

I'm not clear on exactly what the author had in mind. The operating band of a system is it's free space transmission frequency. And the information bandwidth of the transmission is what it is. Yes, one can mix a 40 and 20 GHz signal to upconvert to 60 Hz. But it's not going to increase the information content.

The implication that 60 GHz amplifiers are easier to build than oscillators because they don't have active components is nonsense. No active components, no gain.

Finally, one of the reasons that 60 GHz is of interest is that it falls into a strong absorption band of the atmosphere. The resulting rapid attenuation of the signal with range is an advantage for short range systems where mutual interference is a concern.

Finally, while the overall assumption that this band will be exploited, silicon is probably not the leading candidate as the material. SiGe mixed signal circuits represents a mature technology that is being already being used in the mass market telecom industry, and InP is being developed that has even higher frequency capabilities. (I've seen one report of an IC with a frequency cut-off of 700 GHz.

This is a follow-up to the previous comment. I reacted to the subtitle "Cheap silicon transceivers broadcasting in this still-unlicensed band may usher in the hi-def wireless home" and scanned the article too quickly. On re-reading it is, in fact, discussing SiGe BiCMOS technology, and not plain Si.