Four of the newer players presented their cases at a panel session during this week's Wi-Fi Planet conference, all of them emphasizing the effect a smart antenna can have on range.
So what is a smart antenna? Most antennas just send signals out in all directions; "smart" ones adjust their power and resources depending on the position of the user or obstacles in the area.
Smart antennas aren't new. Companies like ArrayComm Inc. are selling them into the cellular world. But lately, antenna startups are targeting the wireless LAN industry. Multiple-antenna schemes are being used by firms such as Airgo Networks and Vivato Inc. to increase wireless LAN performance, for example. (See ArrayComm Has Its Chips, Airgoooooooooooo! , and Vivato Plans Ambitious WLAN.)
With range being more of an issue than speed on WLAN networks, smart antenna technology could boost the ability of network designers to reduce costs by improving the area covered by each access point.
The technologies could also help wireless ISPs (WISPs) reach more subscribers cheaply, an important point considering the difficulty they've had making money. "WISPs go bigger and bigger to reach more customers, but they never see the profit/loss margin they need," says Jack Nilsson, chief scientist of Wi-Fi-Plus Inc. Smart antennas come in a dizzying variety of approaches. Consider the four on the Wi-Fi Planet panel:
- Bandspeed Inc. disclosed its Gypsy antenna in April (see Bandspeed's Six-Eyed Gypsy ). Gypsy uses a directional approach, making antennas more efficient by narrowing their focus. The system splits the 360-degree universe into six 60-degree sectors, with antennas tracking each sector rather than a full circle. Customers using Bandspeed's technology are expected to ship at the end of next quarter.
- Motia uses analog processing techniques to derive four signals from an 802.11 transmission. It uses a weighted combination of the four to determine where the sender was, then uses the same set of weights to transmit signals back. The process gets repeated for every packet, so the antenna can track a moving user. Antennas using the technology should be available next year (see Motia Launches Javelin).
- Wi-Fi Plus exploits polarization to grab signals thrown away by other antennas. It's polarization that causes signals to weaken as they reflect off walls or pass through objects, Wi-Fi Plus's founders say. The company's antenna is designed to pick up those polarized signals. Wi-Fi Plus is shipping antennas but would like to get its product embedded into other companies' cards.
- ZeeWaves Systems Inc. is another advocate of the directional approach. The company's antenna can broadcast in 360 degress as a normal antenna does, but it can also narrow the angle to as little as 10 degrees. ZeeWaves' products are in beta trials.
Not everybody believes 802.11 needs a range boost. Companies such as Tropos Networks, for example, are using short-reach 802.11 cells meshed together to create better coverage. And switch startup Aruba Wireless Networks thinks access points should stay dumb and cheap, so that if particular users are out of range, it's affordable to just install an extra AP for them. (See Tropos Taps Intel and Aruba's Switch Pitch.)
The cost question presents a barrier to the smart antenna crowd when it comes to wireless LANs, says Jack Winters, chief scientist for Motia. "Chip vendors and AP vendors are very reluctant to put a 'Super AP' on the shelf that's 30 percent more expensive than everything else."
To counter that problem, smart antenna vendors might want to emphasize that they supposedly can cut the number of access points needed. "They might spend $100 on the antenna but find they save $1,000 on the APs," says Khurshid Qureshi, CEO of ZeeWaves. Another challege is that more players continue to join the field, such as stealthy Wavion Inc., which is developing some kind of outdoor antenna (although it might not be targeted at wireless LANs). The firm picked up $6 million earlier this year, a round that was extended to $12.5 million in October, according to the most recent quarterly filing from lead investor Elron Electric Industries Ltd. (Nasdaq: ELRN). (See Wavion Picks Up $6M.)
— Craig Matsumoto, Senior Editor, Light Reading