Abstract: A method for increasing the interrogation range of an RF Tag in a radio communication system using RF Tags with two reflecting antenna elements. The second reflecting antenna element is predeterminately positioned, and preferably aligned, with respect to the first reflecting antenna element in the direction of expected incident RF radiation and is spaced from the first reflecting antenna element at a predetermined fixed distance. The first and second reflecting antenna elements are alternately pulsed on and off such that while the first reflecting antenna element is in a signal reflecting operating state, the second reflecting antenna element is in a substantially non-reflecting state and vice versa. The alternate pulsing and predetermined fixed spacing between the first and second elements generates a known phase difference between the reflected signals of the first and second reflecting antenna elements.

Abstract: This invention reduces near-end crosstalk between identical discrete multi-tone (DMT-type) modems by introducing the following modifications to modems at a central office or a subscriber premises. The modifications include: a mechanism for aligning the frames of all modems at the central office (CO), a mechanism for aligning the frames transmitted by the subscribers' modems with the frames received by those modems, and lengthening the DMT frame to include a cyclic prefix. The cyclic prefix to a frame has been made longer than twice the maximum round-trip delay, that is, the delay between the central office and the most distant subscriber to be served. By making adjacent DMT carrier frequencies be orthogonal to each other, the aforementioned modifications will reduce both Near End Cross-Talk (NEXT) and Leakage-Excited Cross-Talk (LEXT). These benefits apply to modems at both the central office (CO) and subscriber ends of the communication path (for example, a high capacity twisted-pair wire).

Abstract: The watercut of fluid in a mulitphase flow is measured. Microwave energy in the 10 Ghz range is transmitted through a test call having flow passing therein through a known geometry. Attenuation and phase shift of the microwave energy is measured and used to derive the wave number of the microwaves in the unknown fluid. The water fraction of the unknown fluid is then determined from the wave number and the known geometry of the test all using Hannai's equation.

Abstract: The present invention encompasses a method of facilitating an audio source change in a digital radio communication system (100). A typical system includes a plurality of audio source units ( 101-103), a plurality of audio destination units (105, 106), and a switching unit (108) for rendering one of the plurality of audio source units (101-103) operable. Upon receipt (302) of an information-bearing frame from an audio source unit, a frame sequence value is identified (304). The expected frame sequence value is then determined (306), and this value is compared to the identified frame sequence value to determine whether or not the received frame sequence value matches the expected frame sequence value. When the frame sequence values match, it is assumed that the frames were sourced from the same audio source unit (i.e., no source change has occurred).

Abstract: A method at comparator (103) of determining the depth of remote buffer (107-109), by computing the difference between the current time and a next launch time, where the next launch time is the time at which a next information packet will be transmitted by the base station (104-106) on the radio channel. The next launch time is determined by the summation of, the time to transmit a previous information packet with error correcting information on the radio channel, and the launch time of a previous information packet. The method further includes maintaining the buffer depth between thresholds such that information packets will not be provided beyond a maximum threshold and filler packets will be provided when buffer depth is less than a minimum threshold.

Abstract: A great many small volume samples are taken, at a high rate of frequency, from a multi-phase fluid stream to determine the respective oil, water and gas fractions. Rapid fluctuations from an all liquid curve will indicate the presence of gas in the fluid.

Abstract: A waveguide and pressure barrier for use with devices for measuring fluid parameters of fluids passing in a pipe under high temperature and pressure conditions and utilizing microwave energy for making the measurements, the device including a pair of substantially identical members adapted to be mounted in spaced opposition on the pipe. Each member has an axial bore with a transverse bore for receiving a microwave antenna. The axial bore is substantially filled with a ceramic glass material providing the pressure and temperature barrier.

Abstract: The means and method of the present invention includes a source of microwave energy and associated elements which provide microwave energy to a petroleum stream. Other circuitry include elements which receive microwave energy from the petroleum stream. Electronic apparatus provides at least one outputs utilizing the provided microwave energy, the received microwave energy and known values for 100 percent oil, 100 percent gas and 100 percent water, corresponding to a ratio of gas to liquid. From the readings of attenuation and phase shift, an estimate of the proportions in the mix is extracted by interpolation.

Abstract: A system determines the relative amounts of phases in multiphase flow, typically the liquid (or gas) fraction of a stream in two-phase flow. More particularly, the system quickly and reliably determines the liquid (or gas) fraction of a flowing two-phase stream, such as a process stream commonly found in chemical processing or in petroleum production operations. The system yields accurate results regardless of the exact flow regime under which the two-phase stream is flowing.

Abstract: A dual frequency microwave water cut monitor includes a microwave source which provides microwave energies at two different frequencies to a circulator which in turn provides the microwave energies to an antenna. The antenna provides the microwave energies to a petroleum stream and also receives reflected microwave energy back from the stream. The reflected microwave energy is provided by the antenna to the circulator which in turn provides the reflected microwave energies as test microwave energies. A detector assembly connected to the circulator detects the intensities of the test microwave energies and provides a corresponding intensity signal. Indicator apparatus connected to the circulator to the microwave source and to the detector assembly provides an indication of the water cut of the petroleum stream in accordance with the intensity signal and the phase difference between one of the source provided microwave energies and its corresponding test microwave energy.

Abstract: A petroleum stream microwave water cut monitor includes test cell means which contains a reference petroleum multiphase fluid sample and which has a sample stream of a petroleum stream passing through it. The test cell is maintained at a predetermined temperature. A source provides microwave energy to one of a first pair of antennae which provides the petroleum stream flowing in the test cell or the reference sample in the test cell with microwave energy. One of a second pair of antennae receives the microwave energy that has passed through either the petroleum stream or the reference sample. A detector detects the received microwave energy and provides a signal corresponding thereto. An indicator provides an indication of the water cut of the petroleum stream in accordance with the received signal power and a phase difference between the source provided microwave energy and the received microwave energy.

Abstract: A co-variance microwave water cut monitor includes a test cell having a petroleum stress flowing through it while permitting the microwave energy to enter the test cell. A microwave source provides microwave energy to a circulator which in turn provides the microwave energy to an antenna. The antenna provides the petroleum stream in the test cell with the microwave energy and receives reflected microwave energy back from the stream. The reflected microwave energy is provided by the antenna to the circulator which in turn provides the reflected microwave energy as test microwave energy. A detector assembly connected to the circulator detects the intensity of the test microwave energy and provides a corresponding intensity signal.

Abstract: A petroleum stream microwave water cut monitor includes test cell means which contains a reference petroleum multiphase fluid sample and which has a sample stream of a petroleum stream passing through it. A source transmits microwave energy to one of a first pair of antennae which irradiates the petroleum stream flowing in the test cell or the reference sample in the test cell with microwave energy. One of a second pair of antennae receives the microwave energy that has passed through either the petroleum stream or the reference sample. A detector detects the received microwave energy and provides a signal corresponding thereto. An indicator provides an indication of the water cut of the petroleum stream in accordance with the received signal power and a phase difference between the transmitted microwave energy and the received microwave energy.

Abstract: The petroleum stream watercut monitor includes a test cell having a petroleum stream flowing through it. A microwave transmitter provides microwave energy through an antenna through an isolator. The antenna irradiates the test cell with the microwave energy so that the microwave energy enters the test cell and is reflected from the petroleum stream back to the antenna. A circulator connected to the isolator connects the transmitter to the isolator means and provides microwave energy to the antenna through the isolator and receives from the antenna again through the isolator the reflected microwave energy. An indicator provides an indication of the watercut of the petroleum stream in accordance with the phase difference between the transmitted microwave energy and the test microwave energy.

Abstract: Apparatus and method for monitoring a petroleum stream includes stratifying the petroleum stream into substantially liquid and gas streams. Predetermined parameters of the stratified petroleum stream are sensed and signals are provided accordingly. A sample of the liquid stream of the stratified petroleum stream is taken and parameters of the sample stream are also sensed with representative signals provided by sensors. Circuitry provides signals representative of the water faction, the gas faction, and the oil faction of the petroleum stream in accordance with the signals from all of the sensors.

Abstract: A water cut monitor includes a microwave transmitter which transmits microwave energy through a fluid mixture containing water. An indicator connected to the microwave transmitter and receiving the microwave energy transmitted through the emulsion provides an indication of the water fraction of the fluid mixture in accordance with the phase difference between the microwave energy from the transmitter means and the microwave energy transmitted through the fluid mixture.