| 摘要 |
The invention concerns a decentralized subscriber access system (1) for broad band networks, with a subscriber access device (3) and an output device (2) wherein the subscriber access device (3) has a power unit for producing a supply of d.c. voltage for an authorisation recognition device to recognise a user authorisation to receive a random bit sequence and to relay a system-dependent or operator specific identifying code or identifying function, read from an access card or a value chip, to an identifying generator to produce a specific identification signal. The transmitted and the generated identification signal can be switched via a supply switch and the d.c. voltage via a d.c. voltage connector and a d.c. voltage supply switch to a signalling line on the output device (2). The output device (2) has an injection switch and an output switch for injecting a random bit sequence and for taking both the identification signal found in the signalling line and the generated d.c. voltage and has a specifically programmed signal recognition device for recognising the specific identification signal as a valid reference echo of the random bit sequence and for delivering a switching voltage to a selection device via which several different transmission bandwidths on the user specific signalling line can be switched on. |
