Abstract: In a light waveguide, the one end of which comprises a flat entering area for the light to be coupled into the core of the light waveguide, the entering area is narrower than the core diameter of the light waveguide and, around the entering area, the end of the light waveguide is laterally sloped up to the entering surface. Only the light which impinges on this entering area passes into the core and is guided therein.

Abstract: The invention refers to a method and an arrangement for netwide call trace with various interfaces and protocol stacks of at least one call within a telecommunication network by using a central call trace server (CS) and local intelligent call trace intelligent agents (IA) between the switching points (SP) of the telecommunication network, said central call trace server being connected with all of said local intelligent call trace intelligent agents IA. The central server manages the intelligent agents and distributes information between the intelligent agents. Only a reduced set of necessary data are sent to the central server by the intelligent agents, in case that the central server requires more data this data are sent by the intelligent agents upon request of the central server. The method and the arrangement allows an exact call trace inclusive of wild cards and calls between different telephone networks (mobile/land).

Abstract: An optical spectrum analyzer of novel design, in which several different spectra can be measured and analyzed simultaneously. A measuring signal is used as a reference signal for calibrating the optical spectrum analyzer. The light rays are admitted via a coupling device with several coupling apertures arranged in a line; and via a separate decoupling device comprising respective decoupling apertures arranged in a line, the light rays are decoupled. Height offset is realized by a 90° deviation prism. The arrangement makes possible simultaneous analysis of several optical lines with little retroreflection as well as uninterrupted calibration of the measuring process.

Abstract: The process to measure the signal quality of a digital information transmission system using a scanning device with adjustable direct current threshold can determine a signal parameter for the signal quality (Q-factor), which can determine the bit-rate from an unknown input signal and with its help a clock signal can be generated to scan the input signal with the scanning device. The device includes a detection device as well as a clock generator, which is connected to the detection device and receives a pre-adjustment signal, and which synchronizes with the input signal over a phase locked loop with the scanning device through phase comparison. Process and device allow the monitoring of systems in a shortest time and facilitate statements concerning the bit-rate of the respective line section as well as concerning the size of the Q-factor and all relating variables.

Abstract: Method and apparatus for non-invasive testing of digital communications systems. Amplitude measurements are made for multiple frequencies of a multi-frequency communication system, converted to the time domain. An adaptive filter output is matched to the time domain representation to characterize the channel. Impedance mismatches may be precisely located using this technique. An error signal representing a difference between a signal transmitted through the channel and a received signal is estimated and analyzed. The error signal is separated into components corresponding to contributions by wide band noise, residual phase modulation, and residual amplitude modulation. Identification and removal of narrow-band interferers may occur prior to this separation. Bit error rate and system margin computations employ a Monte Carlo simulation of the various error sources. This provides a well refined estimate of bit error rate and system margin.

Abstract: A method, system and apparatus for frequency sweeping and frequency sweep testing a CATV system wherein the CATV system has a plurality of channels and is transmitting television signals over at least some of the channels. The system includes a head end test unit coupled to the CATV system at its head end and a remote test unit coupled to the CATV system at a location remote from the head end. The head end test unit sweeps the CATV system by either generating and transmitting test signals at the channel frequencies over the CATV system or, if a television signal is being transmitted on a channel, using the television signal as the test signal. The head end test also measures the signal levels of the test signal and at the end of the sweep, transmits telemetry signals, which include the frequencies to be swept and the measured signal levels, over the CATV system to the remote test unit using the same transmitter that it use to generate and transmit the test signals.

Abstract: An exemplary leakage tagging signal generator according to the present invention is intended for use in connection with a leakage tagging signal detector that detects signal leakage in a communication system. In particular, the leakage tagging signal generator is intended for use with a leakage tagging signal detector that identifies leakage tagging signals based on the detection of a characteristic leakage tagging frequency component. The leakage tagging signal generator includes an RF signal source, an output, a switch, and a pulse signal source. The RF signal source is operable to generate an RF carrier signal having a first frequency. The output connects to the communication system. The pulse signal source is a device operable to generate a pulse signal having a first state and a second state, said pulse signal having a pulse period.

Abstract: Method and apparatus for non-invasive testing of digital communications systems. Amplitude measurements are made for multiple frequencies of a multi-frequency communication system, converted to the time domain. An adaptive filter output is matched to the time domain representation to characterize the channel. Impedance mismatches may be precisely located using this technique. An error signal representing a difference between a signal transmitted through the channel and a received signal is estimated and analyzed. The error signal is separated into components corresponding to contributions by wide band noise, residual phase modulation, and residual amplitude modulation. Identification and removal of narrow-band interferers may occur prior to this separation. Bit error rate and system margin computations employ a Monte Carlo simulation of the various error sources. This provides a well refined estimate of bit error rate and system margin.