Earlier this month, Fujitsu announced that its new BroadOne WX series of base stations for the mobile WiMAX market would officially be launched at of the GSMA Mobile World Congress 2008 February 11-14 in Barcelona, Spain. (Ref: Feb. 6 company news release). Here's the Fujitsu link to a picture of the product and the spec sheet. The announcement was made from Fjuitsu Network Communications in Richardson, Texas in the USA. That arm of Fujutsu is noted for its innovation in wireline and wireless networking solutions for solving what they term "critical business issues" and new services. It has the support of Fujitsu Limited of Japan, which is now a $43.2 billion company with over 160,000 professionals in more than 100 countries. With that kind of clout, potential buyers of GaN-based base stations just might start thinking GaN over LDMOS.

The reason this announcement caught my attention and moved it to column-worthy status is because of Fujitsu's longstanding expertise in compound semi HEMT development. Way back when epitaxy for compound semi electronic devices first came on the scene, there was a race of sorts between GaAs HBTs and GaAs HEMTs. One year HBTs ruled, then HEMTs, then it became a great race to see which would make the next breakthrough in performance and reliability. Fujitsu was always on the side of HEMTs, led by Dr. Abe, while most everyone else, thanks largely to Rockwell Science Center and Peter Asbeck (who went on to become a professor at UC San Diego), hopped on the HBT bandwagon.

Then GaN came along as the newest, most wonderful compound semi material and most of the GaN electronics focus turned to GaN HBTs as the shining hope, especially for replacing big bulky silicon-laden base stations. "Instead of those buildings at the base of the towers, you can simply attach a GaN HBT-based base station on a pole." That's what we heard, and that got GaN electronic developers very excited. Various people championed GaN HBTs, but they evidently didn't get the needed support and capital to get the job done fast enough, and LDMOS took the lead. All of a sudden, talk about GaN HBT base stations died off. I figured silicon won again. Drats!

Now here comes Fujitsu, leveraging its decades of HEMT expertise, and Viola! The words "GaN" and "base stations" are back in the news. Hurray! From what I can see, what the GaN electronics guys need to do next, is get trucking and jump on the bandwagon again. HEMTs or HBTs... it probably doesn't matter which you're into. The trick is to get the notion of "GaN base stations" firmly planted in the minds of the people making the decisions as to what technology to chose for base station upgrades and new installations. GaN guys need to do classic due diligence on what Fujitsu is fielding and take off from there. Gloss over the marketing hype and concentrate on the technology.

The first base station launched in the Fujitsu series is called the BroadOne WX300 outdoor macrocell base station. Features include higher transconductance, improved linearity and thermal management, and has higher cutoff frequencies than competitive products. The main feature is that they're so small and light that they weigh less than the OSHA single installer limit, whch makes them easier, cheaper and quicker to put into service or take down for maintenance work. And the BroadOne WX300 Macrocell base station is available in three configurations: standalone, multi-sector and split architecture. In the multi-sector configuration, the platform is scalable up to three sector configurations by connecting additional units to the first BroadOne WX300 and the master unit provides timing and capacity aggregation to provide an extremely flexible system. The split architecture configuration is for situations when multiple forms of redundancy are needed. And Fujitsu offers a dual architecture that combines an indoor baseband and an outdoor RF head macrocell base station for wide-area transmission. They also promise that an indoor compact base station will also be available... "in the future." The three models have been designed for the 2.5 GHz and 2.3 GHz frequency bands, which have widespread global acceptance now.