Developments aim for efficient interactivity

Cable TV operators' interest in interactivity is driving technology that will be highlighted at the Cable-Tec Expo '96 in Nashville (see related story on page 28).

As CATV networks evolve toward a fiber-to-the-node architecture to support interactive services, the need for more bandwidth per household in the upstream channel becomes a greater concern. To help meet that demand, Phasecom Inc. is announcing an addition to its Reverse Channel Spectrum Organizer product family that is designed for neighborhoods divided into three service quadrants.

The addition, called the P4143, multiplexes three reverse channels onto one fiber, reducing costs for cable operators, said Shaul Berger, chief executive officer of the Cupertino, Calif., company. Each Spectrum Organizer installed in place of a fiber trunk means one less transmitter, receiver and transverter to pay for and install for networks without reserves, he said.

Also, Ortel is introducing a return-path laser that costs significantly less than forward-path distributed feedback (DFB) lasers, said Larry Stark, Ortel's vice president of broadband market development. The 1651/B lasers use a high-temperature DFB chip design that ensures chip performance over a wide range of temperatures, eliminating the need for internal coolers. It also provides up to 200 MHz of bandwidth and helps keep out static from external sources.

Cable upgrades are creating a tremendous demand for laser hardware, said John Mansell, a senior analyst with Paul Kagan Associates. Although 6% to 8% of today's 62 million household subscribers are served by two-way systems, projections show the number will grow to 40% to 50% by 2000, Mansell said.