Aperto introduces wireless products suite

Aperto Networks has introduced a “second generation” suite of fixed broadband wireless products that operate in the 2.5, 3.5, 5.3 and 5.8 GHz frequency bands.

The products--base stations, subscriber units, radios and antennas--deliver on-demand bandwidth allocation, subscriber connection optimization and carrier-class quality of service, said Alan Menezes, Aperto’s marketing vice president.

Aperto employs an advanced TDMA interface protocol that uses a burst mode both upstream and downstream and on-demand allocation of time slots and packet size, Menezes said. It delivers up to 20 Mbps of data in a 6 MHz channel for up to 10 to 12 miles, although it will be most effective in the four to five mile range.

“It also supports flexible duplexing,” Menezes said.

Although future products will support frequency division duplexing (FDD), the initial product line will rely on time division duplexing (TDD) to use a single channel for both upstream and downstream transmission.

“(TDD) allows you to adapt the bandwidth allocation between upstream and downstream, depending on your traffic requirements,” he said. “This isn’t possible with FDD; it’s pre-fixed and you can’t change it.”

Menezes said the subscriber connection optimization, which allows the service provider to dole out power levels based on a number of parameters, lets wireless service providers more efficiently offer and deliver service to a greater number of subscribers.

“For the subscriber who had ideal conditions close to the cell tower, we would use a lower power, because we don’t need to use higher power and create more interference for adjacent cells,” Menezes said.

Additionally, Aperto’s system might use a high order modulation scheme, less error correcting codes or antenna diversity in this mode.

“For someone who’s farther out, more challenging, we might use higher power,” he said. “You might use a more robust modulation scheme, maybe a different antenna diversity, maybe a higher order error correcting encoding. On a burst-by-burst basis, we can actually change the parameters to each subscriber.”

This sort of optimization is essential as wireless operators abandon 30-35-mile supercell configurations and adopt multi-cellular approaches, Menezes said.

Unlike many broadband fixed wireless approaches, Aperto targets the residential and the small-to-medium sized business market, Menezes said.

“In many ways, this competes with cable and DSL. It’s also complementary to cable and DSL, because, in many cases, people just can’t get services,” he said. “We’ve solved some real-world problems, solved some of the interference mitigation management issues, so you can build multicell networks; some of the line-of-sight, obstructed line-of-sight, non-line-of-sight issues so that you can expand the number of subscribers that you serve.”