At the transmitter site, the cable signal is fed directly to the transmitter in the frequency range of 54 to 600 MHz.

At the receiver site, the microwave receiver connects directly to the local cable network without the need for frequency converters or any other equipment.

The microwave system provides Cable TV service to the cable subscriber in the Is¬lands without the need to install a new headend.

Miranda Chen, CINET Vice President, says “we are very pleased with the quality of the signal and the level of support from Cable AML during installation and commissioning of the system.”

The microwave system consists of a broadband outdoor transmitter operating in the 12.7 to 13.2 GHz band, feeding two paths simultaneously. At each of the receiver sites, the local receiver feeds the local cable network directly.

The microwave system allows Mount Baker Cable to continue to offer upgraded Cable TV service to the two Island communities.

Dan Adams, General Manager of the Cable system, mention “I am very pleased with the quality of the signal and the level of support from Cable AML during installation and turn-on of the system.”

The same transmitter originally installed to service San Andres and Eronguaricaro provided the signal required to the new town of San Jose through a Repeater, allowing the company to start cable service in San Jose from the Quiroga headend without the expense of a new headend. Ing. Alejandro Baltazar said, “The capability to expand the microwave system is creating opportunities for our company to provide Cable TV service to nearby towns in a very cost effective way, without the expense of a long fiber run or a new headend.”

The digital TV signals originate in the existing digital MMDS system in the country’s capital, Dakar. A microwave link using broadband microwave radios from Cable AML is used to transport the digital signal 14 Kms to a repeater point at Kissane. From Kissane it is relayed to two new MMDS sites, one at Thies 10 Kms away and the other at Mbour, 28 Kms away. A broadband MMDS transmitter then re-transmits the signal for local subscribers at the two cities.

The installation and commissioning of the system has been under the technical direction of David Vine, who has previous experience with both DTT, MMDS and digital cable systems.

Mr. Vine said,“Duplicating the Dakar headend in Thies and Mbour would have been cost-prohibitive, With Cable AML’s equipment, we are able to provide excellent signal quality to residents in these two remote communities.”

The Headend was built on a ridge near the city. The very low look angle to geostationary satellites serving CONUS, requires satellite receive antennas in Alaska to be constructed on rises or on manmade structures.

The link interconnects the Headend with the central data site in the city center. Right-of-way issues and the high cost of constructing a fiber link made a microwave link the only feasible solution.

Santa Clara University operates a large a state-of-the-art video and data network to provide connectivity services throughout campus. The microwave link provides video services to an area within the campus that can not be reached easily with fiber.According to Terry Benton, Manager of Linc-TV Services at Santa Clara University (California, USA), “we are very pleased with Cable AML’s fast response to our requests and the professional installation services provided for this upgrade.”

Fourteen receiving points downconvert the backbone signal to the conventional 54 to 870 MHz spectrum and feed rack-mounted Demodulators. The Demodulators feed signal to existing CATV systems that had never previously been interconnected.

A Cable AML MMDS transmitter in Salt Cay delivers analog signals from Grand Turk directly to subscribers.

The system will expand to three videos with their stereo audios in the next phase. The backbone can accommodate more than 200 video programs.

The wireless HFC system was selected over the two other possible alternatives: a fiber link from the Safford headend or a stand-alone headend. The main reason is that it is much more cost effective, which is a significant consideration when providing service for areas with under one thousand subscribers.

The Morenci system had previously received off-air broadcast signals from Safford via a two-hop FM microwave system. The links are 23.3 and 11.7 miles long respectively, for a total of 35 line-of-sight miles.

Cable One decided to implement an all-digital service. The microwave system operates with multiple carriers, all with 256-QAM modulation. The initial 13 GHz downstream transmission rate is 814 Mbps, but the system has capacity to transmit upwards of 3 Gbps.

The 18 GHz upstream was designed to accommodate multiple 16-QAM signals from each of the four nodes. With the increasingly symmetrical nature of subscriber data traffic, more than one upstream channel was required. Cable AML developed a synchronized, block-conversion system to transport four independent upstream channels (each from 5 to 42 MHz) through the two-hop microwave system back to Safford for integration into the CATV return network.

The upstream service in the 18GHz band required the installation of new antennas and waveguide jumpers at the transmitter site at Morenci, the repeater at Guthrie Peak and the receiver at Safford.

The company chose a Cable AML microwave system consisting of a transmitter at the Headend in Huejutla, a repeater at San Francisco and receivers at each of the 3 towns.

Rugged terrain between the towns posed an enormous challenge. The trip up the mountain at San Francisco was so treacherous that vehicles and pack animals were not an option. All the equipment was all carried by people on foot, then assembled onsite by company engineers.

Fiber was an unlikely option due to the terrain, but if it had been possible to run cables between the various sites, it would have cost as much as five times more. Instead, the company was able to deliver Cable TV service to the three towns efficiently and at a much lower cost.

While Servicio Telecable Huejutla has no immediate plans to provide Internet service, the Cable AML system can be upgraded in the future to two-way service. Mmds digital system upgraded in Lithuania’s capital city.

The company chose a Cable AML microwave system consisting of a transmitter at the Headend in Huejutla, a repeater at San Francisco and receivers at each of the 3 towns.The islands of Molokai and Lanai and the isolated town of Hanna in Hawaii receive Cable TV signals (54 to 600MHz) from the main Headend in Maui via 13GHz broadband microwave links from Cable AML. Time Warner wanted to expand this carriage to include the 256-QAM digital video services (with carriers above 600MHz on the Maui cable system), but regulatory bandwidth limitations in the 13 GHz band made it necessary to use the18 GHz band for the digital carriers.The 15 mile link to Lanai and the 13 mile link to Molokai, both over water, were straightforward for the 256-QAM digital video.

The link to Hanna was more demanding due to two factors: a longer distance and the existing double passive reflector (billboards) in the path. The reflectors were designed for 13 GHz and had unknown performance characteristics at 18GHz.An additional requirement was that the link had to work using existing 13 GHz antennas at the transmitter site in Maui due to size restrictions imposed by National Park authorities. This was accomplished by using specially designed dual-frequency feed horns sharing the same antenna aperture.

Howard Feig was the Time Warner Engineer who designed, installed and commissioned the microwave hardware manufactured by Cable AML for this link. According to Howard, “Cable AML once again has provided an excellent solution for a very demanding link, continuing a tradition of good quality equipment and service lasting for over 15 years.”