Abstract: A system and method for accessing digital content purchased by a rights owner for a first computing device. The method receives a proxy from the rights owner that includes rights to the digital content granted to the rights owner, stores the proxy on a second computing device, and determines whether the rights owner is present at the second computing device. When the rights owner is present at the second computing device, the method enables the proxy, and accesses the digital content on the second computing device through the proxy.

Abstract: A digital recorder detrunks calls for logging prior to recording same. This allows retrieving what a radio monitoring a particular talkgroup hears and combines that with the best features of a detrunk-on-playback system, namely the ability to isolate those portions of all the system communications which are desired or specifically excluded. The fluid associations between talkgroup IDs, multigroup IDs, and supergroup IDs are used by the recorder to search for the audio which the user wishes to hear. The retrieval of audio heard by a particular, individual radio is made possible through the incorporation of radio affiliation information into a searchable database. A specified individual radio ID may be tracked with respect to its talkgroup affiliations, during a specified time interval, by an appropriate search algorithm. Those affiliations can, in turn, be further used with the talkgroup/supergroup/multigroup search algorithm to retrieve the audio heard by an individual radio user.

Abstract: An operator MUX interface (OMI) (102) includes a data base manager (203) that manages at least two data bases. The first comprises a substantially non-temporary data base, and the second comprises a substantially temporary data base. The latter includes information from both the first data base, and other information as well. The data base manager (203) automatically alters the data storage structure of the second data base whenever either the data storage structure for the first data base is changed, or whenever new information must be added to the second data base, and the data storage structure of the second data base will not readily accommodate that addition.

Abstract: System configuration data required for use by various interfaces (102) can be obtained either directly via a data link (104) that couples the interfaces to other systems (109 or 111), or by a down link from a system data manager (106) configured as part of the interfaces' system (100).

Abstract: Optimal sum-frequency and second harmonic generators are fabricated in ferroelectric waveguides by taking into account the interference between generated beams of Cerenkov radiation.

Abstract: An M.times.N coupler uses a planar waveguide to couple each of M input channel waveguides to each of N output channel waveguides, the input guides and the output guides being disposed on opposite sides of the planar waveguide. Uniformity of coupling is improved by joining the input channel waveguides to the planar waveguide in a manner to focus the beams emitted by each input guide into the planar waveguide at a common focal point located near the center of the edge where the output guides join the planar waveguide.

Abstract: A TE-TM mode converter utilizes a Y-cut lithium niobate crystal which includes a straight titanium-diffused channel extending along the Z-axis of the crystal. A parallel pair of electrodes lie symmetrically on opposite sides of the channel. a.c. and d.c. voltage supplies are connected to the electrodes to supply voltages so as to effect complete conversion from one direction of polarization to the other direction of polarization of a wave applied as an input to one end of the channel for abstraction at the opposite end.