| 摘要 |
Diverse communication terminals attach via broadband radio to a communications network at any of typically three hierarchical cell sizes; picocells (1), standard cells (2) and macro cells (3), increasing from, typically, a single building to a city to a region. Almost all telecommunications traffic transpires, however, within the lowest levele picocells (1) to and from low cost base stations (11) that have typically one radio transceiver (111), four optical transceivers (112) an ATM switch (11) and an ATM controller (114). Each local base station (11) is interconnected to a regional end office switch (12), where a connection to a worldwide wire/fiber line communications backbone (4), upon a multi-hop mesh network (100) via short highly-focused free-space broadband directional optical links (10). By this free-space wireless broadband access, subscriber service requirements on the order of 20 Mbps peak rate and 10 Mbps average are provided. |
