| 摘要 |
<p>A fiber optic hub (10) for local area networks (15, 35) and other data communication systems including an internal self-diagnostic and cable test capability for permitting off-line testing of the hub (10) and of fiber optic cables connected to the hub (10). The hub (10) includes a plurality of optical interfaces (30a-30p) each having an optical receiver section (36) and an optical transmitter section (37) and hub-processing circuitry (32) connected to the optical interfaces (30a-30p) for processing data signals received by the optical receiver sections (36) and for providing the processed data signals to the transmitter sections (37) to be transmitted back through the network (15, 35) thereby. Hub (10) further includes a test signal source (61) for generating a test signal to be transmitted from the transmitter sections (36) of one or all of the optical interfaces (30a-30p), and a test signal detector (80) connected to the receiver sections (37) of the interfaces (30a-30p) for detecting a test signal received by any of the receiver sections (37) and for generating an error indicator signal when the received test signal differs from the transmitted test signal. The transmitter and receiver sections (36, 37) of any hub optical interface (30a-30p) can be conveniently tested by looping a fiber optic cable from a transmitter section (37) of any optical interface (30a-30p) to the receiver section (37) of any other optical interface (30a-30p) and monitoring an error indicator (light emitting diode) (80) illuminated by the error indicator signal. The hub (10) also provides a convenient means for testing fiber optic cable connected to the hub (10).</p> |
