June 28, 2005 Leave a comment
At TI, we invested heavily to help our customers deliver WiFi in some of the first wireless PDAs. One of our first efforts was to create our own PDA reference design (so called “Wanda”) using TI OMAP, WiFi and Bluetooth technologies. In doing so, we came across and solved a number of challenges that eventually made it possible for our customers to deploy world-class products, such as resolving WiFi/Bluetooth coexistence issues on the 2.4GHz band and optimizing WiFi for low-power in a battery powered product. Here’s an article talking about the work we did on “Wanda”: EE Times – “Tri-wireless roaming gets kick-start” -http://www.eetimes.com/electronics-news/4132694/Tri-wireless-roaming-gets-kick-start-item-1
Eventually, this work was picked up by a number of TI customers, including HP who used TI WiFi and Bluetooth chips across their entire portfolio of iPAQ devices. This article by Information Week in 2005 summarized a then-widely adopted HP iPAQ4355 using TI’s wireless solutions.
- Information Week – “An Inside Look at the iPAQ 4355″
- “We worked directly with HP to understand what needs to happen for wireless LAN to fit better in the mobile space,” says Matt Kurtz, a senior business development manager at TI. “We worked hard on the low power aspect, particularly getting in and out of low power modes. The standard wasn’t necessarily written with low power in mind. So it was an accomplishment to achieve the level that we did.”
The goal was to be below 3 mA for the non-transmitting (standby) mode. Other devices with similar functionality were pulling in 20 to 25 mA. Another key feature is that the device is housed in a 12- by 12-mm package.
One of the challenges that the HP system designers had to deal with was the Bluetooth-Wi-Fi coexistence. “The 6100 was the first device available that could co-exist between Bluetooth and wireless LAN,” claims Kurtz. “It essentially multiplexes the usage so you don’t get into a race condition where the Wi-Fi starts getting fall-back interference and takes longer to transmit, potentially taking you down to 1 Mbit/s on the wireless LAN.”
All in all, if you look at the timing of this PDA, it really is an exceptional design. Some of the ICs that have been announced since the 4355 was designed will have immediate performance improvements. But for it’s day, it really was (and continues to be) a winner.