| 摘要 |
Communication links are quickly and reliably established between units of a cordless telephone configured for operating in a frequency hopping system. This is achieved through specific processes which detects frequency hopping patterns that are embedded in radio frequency noise. A first process is executed by the base unit and/or each of multiple handset units in the cordless telephone for performing a link acquisition with another unit, also in the cordless telephone. In the execution of this process, multiple profile scans of the frequency hopping channels are executed to build up over time tables with information about energy in all of the channels in the frequency spectrum that are used by the units in the cordless telephone for frequency hopping. In the tables will be spectrum energy from a frequency hopping base unit or handset unit that appears as a recognizable pattern. By applying correlation techniques to the pattern in each table, information is obtained which reflects the probability that a hopping pattern for an associated unit in the cordless telephone has been detected. The unit obtaining this information is then able to quickly join the frequency hopping cycle of the detected base unit or handset unit. An abbreviated second process also is executed by each of multiple handset units in the cordless telephone for performing a link acquisition with another unit, also in the cordless telephone. In the execution of this process, multiple profile scans of the frequency hopping channels are executed to build up over time tables with information about the energy in some minimum number of channels that are used by the units in the frequency spectrum. This process is executed when the searching unit has previous information as to the possible location for the hopping unit in the frequency hopping cycle. In this process, the frequency hopping cycle is easily detected and synchronization with this cycle quickly obtained.
|
