Vyyo aims to lend more symmetry to asymmetric systems. The company just made upstream 16 QAM and upstream QPSK available in its broadband fixed wireless modulation schemes.
Vyyo says its three current downstream modulation schemes — 64 QAM, 16 QAM and QPSK — are designed to let carriers optimize networks for different customer applications. But symmetry help comes from high data rates upstream, through 16 QAM modulation allows symmetric services, such as voice, multimedia and video conferencing, it says.
The upstream schemes target carriers who use a supercell configuration — a large cell encompassing a large region — to increase capacity by assigning 16 QAM modulation to users closer to the base station and QPSK modulation to users further off.
Likewise, carriers who use several small-cell or multicell configurations can use the 16 QAM to double capacity and coverage area of the small cells, Vyyo says.
The result is a system intended to allow carriers "to respond to the trend of adding voice capability to data applications, and maintain their network in the same base station," spokesman Keith Doucet says. Carriers can add subscribers, voice capability to data products or give users higher data rates, he adds.
The modulation doesn't take any new hardware, and is installed via a software upgrade to the network management system.