摘要:
An analog-to-digital (A/D) circuit comprising a multi-pole gain stage, a quantizer, and a feedback stage is stabilized when an analog input signal is excessive in the following manner. A stabilization detector continually samples a representation of stabilization of the A/D circuit. When the representation of stabilization is unfavorable, the stabilization detector increases, via a stabilizer, phase margin by adjusting the pole locations of the multi-pole gain stage based on the degree of unfavorability of the representation of stabilization. With the increased phase margin, the A/D circuit continues to provide digital representations of the analog input signal.
摘要:
A noise source (113 or 217) is coupled to an analog-to-digital converter (115 or 219) so as to remove at least some unwanted spectral components from the analog-to-digital converter (115 or 219) output. In one embodiment, the noise source (113 or 217) is comprised of a sigma-delta digital-to-analog modulator.
摘要:
A transmitter has an oscillator (101, 201, 303, 401, 501) that operates at frequency k multiplied by f.sub.c, thus the oscillator (101, 201, 303, 401, 501) outputs a signal at an output frequency, kf.sub.c. Coupled to the oscillator (101, 201, 303, 401, 501) is a frequency modifier (103, 205, 307, 405, 505), for modifying the oscillator output frequency by factor 1/k, thereby producing a signal at frequency f.sub.c at the frequency modifier output. Coupled to the frequency modifier output is a modulator (105, 215, 301, 407-417, 507-517) for producing a modulated output signal substantially centered at frequency f.sub.c.
摘要:
An analog signal having an input level is provided. The analog signal is converted into a digitized representation of the analog signal in an analog to digital converter (105) that uses an operating range. The digitized representation of the analog signal is processed (107) to determine the input level for the analog signal. The input level for the analog signal is compared (109) with a reference signal to provide a comparison signal. The comparison signal is manipulated (111) to adjust the operating range.
摘要:
A improved microwave dielectric oscillator module which is provided with a removable temperature compensated dielectric resonator channel element is described. The removable temperature compensated dielectric resonator channel element cooperates with an electrically shielded housing. A substrate is mounted within the housing. Microstrip or stripline conductive patterns deposited on the substrate couple energy from the removable dielectric resonator to the remainder of the oscillator circuitry. The oscillator achieves wideband operation utilizing a GaAs FET transistor as the oscillators active element in conjunction with an intergral trombone-line phase adjuster.
摘要:
Disclosed are methods for extracting and using information about an entity that has a presence in a number of information domains. The entity has separate identifiers in each of several domains. Various techniques are described that bind together the identifiers of the entity across the domains. The results of the binding are provided to an interested party that can review information extracted about the entity's behavior in the multiple domains. The interested party is not given access to information that would compromise the confidentiality of the entity. A trusted broker has access to information about the behavior of the entity in the several domains. The broker analyzes that information and provides the analysis to the interested party, again without compromising the confidentiality of the entity. An “incentivizer” works with the broker to extract from the domains information that would be useful in binding together the different identifiers of the entity.
摘要:
A method and apparatus for providing a service from an application service provider to a client in a communications system including a network proxy describes a first step of defining services provided by the service provider as Extensible Markup Language (XML) metadata. A next step includes defining services desired by the client as XML metadata. A next step includes collecting the XML metadata from the client and service provider. A next step includes comparing the client XML metadata against the service provider XML metadata. A next step includes providing the substantially matched service from the service provider to the client upon the finding of a substantial match between the client metadata and the service provider metadata.
摘要:
An RF filter (100) includes a ceramic resonator (116) sandwiched between first and second compensating discs (114 and 120) for temperature compensation, low loss mounting and heat sinking of the ceramic resonator (116). Good thermal contact between the ceramic resonator (116) and discs (114 and 120) is produced by a compressive force applied by copper plates (112 and 128) and copper can (124). The resonant frequency of the RF filter is tuned by means of a copper-plated tuning shaft (104) and ceramic tuning slug (118) which are positioned by brass bushing (134) in copper pipe (130 and 132). Input and output signals are coupled to the RF filter via respective probes (122).
摘要:
A data message (201) is transmitted (301) to a plurality of communication units (103, 105, 107, and 109). The data message (201) is received (401) by the plurality of communication units, which determine (403) whether the quality of the received data message is acceptable. When at least one of the plurality of communication units determines that the received data message is of unacceptable quality, the at least one of the plurality of communication units transmits (411) an energy burst (203) in a predetermined time window. Upon detection of the energy burst (203), the transmitting device may retransmit (309) the data message to the plurality of communication units.
摘要:
In accordance with the present invention there is provided a bandpass T filter and power splitter for electromagnetic energy. It is composed of a plurality of resonant elements serially arranged to form a plurality of forward multi-pole bandpass filters. At least one resonant element is common to both signal paths. The common resonant element transfers energy from the common path to the independent signal paths to effect a power split. The two signal output paths are isolated from one another by a multi-pole bandpass filter. The resonant elements may be composed of either resonant waveguide cavities or dielectric resonators.