Real-World Study: D Block Spectrum Is Essential

A consulting firm headed by an admittedly sympathetic D Block promoter performed a real-world test of public safety broadband wireless, and concluded that 20 MHz of contiguous spectrum is needed, and recommended those frequencies come from the 700 MHz band of D Block. The San Francisco Bay Area Urban Area Security Initiative UASI hired Andrew Seybold Inc. earlier this year to perform the testing from several locations and under several different conditions. Andrew Seybold has been a vocal supporter of legislation that would allocate the D Block to public safety, which in turn would provide more spectrum for wireless broadband. That additional spectrum would, again in turn, provide more advanced capabilities for field units to handle complex, multi-site or multi-agency incidents. During the Seybold tests, the company took Panasonic laptops connected via USB to LTE wireless modems, which had exterior-mounted vehicle antennas. The test involved three scenarios: a bank robbery with potential hostage, a multi-story fire and a multi-vehicle accident. All the scenarios included multiple units from several public safety and allied agencies and private companies, all needing high-bandwidth data carrying video and data streams. The consultants analyzed how the LTE network could handle the needed data streams, and graphed the results. On a 10 MHz network, the system would only handle the data load if units were located close to a cell antenna. Read Andrew Seybold’s explanation of the study, download (pdf) the entire study here, and view a results graph after the break.

This graph from the Seybold broadband wireless study shows how a 5+5 MHz LTE network would handle a barricaded hostage incident for downloads (left) and uplinks (right). Only the Near Cell uplink category could be handled by 5+5 LTE (green & blue).