The FCC’s recent rule changes in the 11 GHz band will lead to an influx in microwave backhaul services and more efficient use of spectrum, says wireless technology group Radio Frequency Systems (RFS). Inspired by ongoing improvements in microwave antenna technology, changes to Part 101 Category B (Cat B) specifications will now permit use of two-foot antennas in the 11 GHz band, without compromising on interference protection.
According to Asad Zoberi, RFS area program manager, the 11 GHz band has to date been under-utilized, due to the costs associated with installing and operating larger antennas to meet Cat A and Cat B specifications. “RFS welcomes this FCC initiative to permit use of smaller antennas,” he said. “The economic advantages will provide an incentive to carriers to make greater use of the 11 GHz band for broadband data and microwave backhaul services. We also predict the introduction of new players into the mix, particularly those providing broadband services.”
Previously, Zoberi explained, the gain, beam width and side lobe requirements of Cat B were difficult to achieve with an antenna smaller than three feet. The revised specifications relax the requirement for beam width and gain, along with side lobe specifications close to the main beam, while maintaining stringency of the balance of the radiation pattern. This permits the use of two-foot antennas, leading to lower overall system cost.
“According to the new Cat B ruling, the RFS CompactLine two-foot antenna (SB2-107) easily meets—and even exceeds—the specifications,” Zoberi said. “In addition, it offers advantages in gain, weight, tower wind-loading and overall depth compared with the other two-foot dishes on the market. This is now the best two-foot solution for 11 GHz microwave link networks where Cat B is permitted.”
The 11 GHz band (10.7 to 11.7 GHz) is an ideal option for point-to-point communications, with links typically spanning five to 20 miles. Its 40 MHz channels allow high-capacity data transfer (3 DS3s or OC3)—a significant improvement on the capacity-limited 10 GHz band, where data throughput of the 5 MHz channels is restricted to 16 DS1s. Furthermore, the 11 GHz band is less affected by rain attenuation than higher bands such as 18 GHz. RFS expects the CompactLine SB2-107 antenna to play a significant role as carriers exploit the 11 GHz band and offer a host of innovative new services. The antenna exhibits all the features and benefits of the RFS CompactLine range of microwave antennas. This includes a robust mechanical design and lightweight construction from corrosion-resistant materials. With best-in-breed performance and meeting FCC part 101 Category B requirements in the 11 GHz band, it will facilitate zoning and site permit acquisition, making it the ideal solution for backhaul applications.