The Swedish Space Corporation (SSC) and Alvarion must surely claim the record for 2.4 GHz long distance links. Their wireless link spanned 192 miles (310km) using Alvarion antennas and 6 watt amps.
The link was made between a stratospheric balloon that was launched from Esrange near the town of Kiruna in northern Sweden and a base station located near Esrange.
The antenna was connected to a 6 watt power amplifier, a camera and a server. Data, such as environmental conditions and weather patterns, was collected and the information was sent back to Esrange via an Alvarion base station which measured 2.4 meters with 6 watt power output and automatic tracking of the antenna using GPS technology.
The weather balloon reached a maxium height of 18 miles (29.7 km) and drifted steadily. It finally touched down east of Sodankyl in the northern part of Finland, having travelled approximately 315 Km.
The round trip ping response at 300Km was 300-500 mSec.
Information received at the base station was then sent back to Esrange via the internal network. The information between the balloon and the base station was transmitted over the 2.4GHz spectrum (2480 Mhz which the SSC is allowed to use with higher ERP) with a stable signal strength of -68 dBm.
A 72 mile long shot beamed by the U.S. Navy across the Pacific Ocean from San Diego to San Clemente Island was deemed to be a disregard for FCC regulations. A followup story reported the link power was reduced by 75% to comply with FCC regulations for the 2.4-GHz band — reducing the link’s throughput from 1 Mbps to 300 Kbps. The owner is reported saying: “any violation of the power limits was unintentional and resulted from the fact that the personnel working [on it] primarily have expertise in computers and not radio technology.”"
Oh, my. Let’s hope they don’t get assigned “Star Wars” duty.
BTW, here’s my story on the Japanese Balloon Bombs of World War II. The Japanese were the first to discover the “jet stream” and used it to launch nearly 10,000 incidiary balloons made of rice paper. It caused general panic in Oregon and along the coast.
