Abstract: An allocation method and system for allocating a least-interfered communications link between a cellular mobile station and a private radio base station within a cellular system is disclosed. A set of candidate carrier frequencies are first selected and ordered by the amount of interference present within the cellular system, and a subset thereof selected. A second set of candidate frequencies and associated timeslots are then selected from the subset and ordered by the amount of interference present in the private radio system environment, and a second subset thereof selected. A plurality of discrete hop lists for each timeslot are then formed, and one of the hop lists exhibiting the least amount of interference is then selected to be applied in the communications link.

Abstract: The invention provides a two-output low-noise down converter circuit which is improved in the isolation between two outputs. In the two-output low-noise down converter circuit, an input signal is divided into two divisional signals of different polarization systems and then the divisional two signals are processed by two-system signal processing circuits which comprise low-noise amplifiers, band-pass filters, frequency converter circuits and a local oscillator, respectively.

Abstract: AMPS (Advanced Mobile Phone System) ST (signalling tone) is detected by a tone detector in which samples of a demodulated signal are amplitude limited to remove click energy, and the limited signal is bandpass filtered, using a notch filter and summer, to limit it to the range of possible ST frequency. Power of the bandpass filtered signal is detected, and compared with detected power of a version of the bandpass filtered signal from which any sinusoidal signal has been eliminated, independent of frequency, to provide for ST detection. A function [x(k)+x(k-2)]x(k-2)-[x(k-1)+x(k-3)]x(k-3) for successive samples x(k) of the bandpass filtered signal is used for the sinusoidal signal elimination. The invention can also be used to detect other tones.

Abstract: A frequency converter includes: a signal synthesizer element for inputting first and second input signals to synthesize these signals and for outputting a synthesized signal, from which noises even times as large as the frequency of the second input signal are removed; an amplitude limitation amplifier element, composed of a differential amplifier circuit, for amplifying the synthesized signal outputted from the signal synthesizer element to output an amplified signal having a constant amplitude; and a filter for inputting the amplified signal outputted from the amplitude limitation amplifier element, to remove an unnecessary signal component to produce an output a baseband signal including only a desired signal component.

Abstract: A communications system allocates communication bandwidth to calls in such a manner for optimizing network system performance. The system uses knowledge about the state of the past and present network demand, and network resources. Predictions of future demand and future network resources are used to calculate future network performance. Allocation decisions are chosen based on network performance calculations and probabilities of achieving future network states.

Abstract: A technique for the automatic alignment and tuning of the front end of a vehicle radio. A tuning voltage is applied to a multiplying digital-to-analog converter before being applied to a front end tuning circuitry of the radio. A tuning voltage antenna number is applied to the tuning voltage at the converter to scale the tuning voltage, and adjust the center frequency tuning of the front end. During alignment, the tuning voltage antenna number is used to modulate the tuning voltage around a mean by reprogramming the tuning voltage antenna number a few values higher and lower in sequence. This modulation of the antenna tuning voltage creates an AC modulation component on the signal strength indicator signal passing through the front end. The signal strength indicator signal is measured and compared to its value before the tuning voltage antenna number was changed.

Abstract: A method of communicating data between points along a fluid flow includes providing a plurality of remotely writable and readable data storage units capable of flowing in the fluid flow; remotely writing data to the data storage units as they pass a first point in the fluid flow; and remotely reading data from the data storage units as they pass a second point in the fluid flow downstream of the first point. The system of the present invention includes a plurality of remotely writable and readable data storage units capable of flowing in the fluid flow; a data writer at the first point for remotely writing data to the data carriers as they pass the first point in the fluid flow; and a data reader at the second point for remotely reading data from the data carriers as they pass the second point in the fluid flow.

Abstract: At least the power portion of the transmitter and the front end of the receiver of a base station of a wireless communication system are advantageously co-located with the antenna (or antennae), typically atop a tower or other elevated feature. Such co-location however exposes the electronics to lightning damage. This is avoided by placement of the electronics and antenna into lightning protection apparatus that is transparent to rf radiation during lightning-quiescent conditions but is a Faraday cage during a lightning strike, reverting to the transparent condition at the conclusion of the strike. This is achieved by placement of the electronics and antenna inside a housing that comprises a dielectric chamber filled with ionizable gas in contact with electrodes selected such that, during a lightning strike, current can flow between the electrodes.

Abstract: A radiotelephone comprising first and second housing portions connected by a hinge, the hinge comprising a mounting structure on the first housing portion; a shaft projecting into the mounting structure and rotatably connecting the mounting structure and the second housing portion and thereby defining an axis of rotation of the hinge, the shaft including a cam portion; spring means located in the mounting structure and including a pair of limbs elongate parallel to the axis of the shaft, the limbs converging to engage partway along their lengths the cam portion so as to apply a rotational bias to it, whereby the first and second housing portions can adopt an open bias position and a closed position; and a transducer located between the limbs in a region beyond the projecting end of the shaft.

Abstract: In a mobile radio communication system of a multi-layer cell structure for covering service areas in layers with cells of different sizes, an enquiry originating mobile terminal transmits enquiry information in an enquiry frame to the N-th layer exchange through the N-th layer base station. The exchange discriminates a kind of the enquiry frame at processing, selects at processing, a minimum cell for covering a distribution area or a minimum number of cells which can cover the distribution area from the state of geographical distribution of the enquiry destinations, fills the numbers of the base stations for forming these cells and the numbers of the exchanges for covering these base stations in the enquiry frame, and transmits this enquiry frame to the corresponding exchange. The exchange checks the numbers of the base stations of the enquiry frame and transmits the enquiry frame to the corresponding base stations.

Abstract: With a CDMA mobile communication system of the present invention, the phase difference sensing circuit of the base station senses the phase difference with respect to a reference phase from the cross-correlation value of the up-link channel signals coming from mobile stations and sends timing control information for compensating the phase difference closer to zero to the mobile stations. Then, in each of the mobile stations, the transmission timing control circuit variably sets the amount of delay in the delay circuit of the modulation circuit according to the timing control information sent from the base station. This enables the transmission timing of the transmission signal of each of the mobile stations to undergo delay control, maintaining the orthogonality between the individual up-link channel signals at the base station.

Abstract: A method and system for increasing capacity and improving performance of a cellular network. The method includes maintaining and analyzing matrices of a cell in the network. One matrix stores performance values and statistics concerning the cell and optimizing conditions for handoff from the cell in response to the performance values. Another matrix stores status values and statistics concerning the cell and optimizing conditions for handoff in response to the status values. A third matrix stores information about cells that should be considered as potential handoff cells.

Abstract: Various methods for terrestrial transmission of digital broadcast signals as DVB, HDTV-T and DAB signals are known. One of these methods is the OFDM method, where the transmitted signal includes a multiplicity of modulated carriers. These carriers are separated in the receiver by means of a Fast Fourier Transformation (FFT). Before being transposed in the frequency domain by the FFT, the analog signal must be sampled. For this purpose a local oscillator controls the timing in front of the FFT. Oscillator imperfections like jitter and frequency offsets can degrade the accuracy of the sampling operation and therefore introduce intercarrier interferences after the FFT. A feedback loop combining the AFC and CPEE process has been designed in order to correct frequency deviations and to reduce jitter of the signal without introducing significant phase noise.

Abstract: A radio card is disclosed that is rigid on one end and relatively flexible on the second end. The radio card's 68-pin connector and radio are mounted on the rigid end of the card, and the antenna, which is advantageously fabricated from a flexible material, is mounted on the relatively flexible end of the card. When the radio card is inserted into a PC Card slot in the wireless terminal, the rigid end (with the 68-pin connector) is inserted first. When the radio card is seated inside the wireless terminal's card slot, the flexible end of the radio card (which comprises the antenna) is flexed so that the plane of the antenna is advantageously parallel to the plane of the slot doors or housing or both of the wireless terminal. When the doors and housing of the wireless terminal adjacent to the antenna is unshielded, the antenna can radiate through the doors and housing and can exhibit favorable radio propagation characteristics.

Abstract: According to exemplary embodiments of the present invention, retractable antennas are described for use in two or more frequency hyperbands. The retractable antennas can include a whip antenna, operable when the retractable antenna is extended and a non-uniform helical antenna, operable when the retractable antenna is retracted. For example, retractable antennas can be designed according to the present invention for usage in portable terminals capable of operating both at 800 MHz and at 1900 MHz. Tuning for the whip antenna is accomplished using a matching circuit. Tuning to both resonance frequencies for the non-uniform helical antenna can be accomplished by varying parameters of the helical structure including, for example, the pitch angle, coil diameter, length and number and spacing of the coil turns.

Abstract: The wireless receiver band is divided into a plurality of smaller bands using a tunable duplexer to produce a first IF signal of a much lower frequency enabling better unwanted signal filtering using a filter of a certain Q.

Abstract: A wireless apparatus is described having a transmitter and a receiver controlled by a frequency synthesizer arrangement to operate on a transmit frequency channel and a receive frequency channel respectively. The transmit frequency channels are not spaced by the same amount in the transmit frequency band as the receive channels are spaced in the receive band, but by a sub-multiple of the receive channel spacing, for example.

Abstract: A system and method for combining the results of different analysis portions to produce a single YES/NO decision regarding the validity of a present cellular telephone call. A soft data analysis portion of the system analyzes soft data, such as the results of a signature analyzer and a customer call profile and determines the likelihood that the particular call is a valid call from an authorized cellular telephone or an invalid call from a fraudulent cellular telephone. In addition, the system performs a deterministic analysis of the particular phone call to independently designate the particular phone call as valid or invalid. The outputs from the deterministic analyzer and the soft data analyzer portion are combined in a combinatorial logic circuit to produce a single binary output having one logic level for valid calls from the authorized cellular telephone and the opposite logic level for invalid calls from the fraudulent cellular telephone.

Abstract: A method and system of adaptive channel allocation in a multi-carrier, multi-slot system is provided. In the method and system a subset of M channels is chosen from a larger set of N channels available for communications on a link. As communications take place on the link, signal quality (C/I) measurements on the channels of the subset of M channels and interference (I) measurements on the channels of the group of N channels are periodically performed. The C/I and I measurements are then used to reconfigure the subset of M channels to reduce co-channel interference on the link.

Abstract: A method and apparatus in a communications system for tracking mobile stations. The length and identify of the path of the mobile station is tracked at the mobile station. The path is monitored for a presence of a loop. In response in identifying the presence of a loop, the loop is removed from the path, wherein the length of the path is reduced. Additionally, the length of the path is compared to a threshold and a location update is performed in response to the length of the path being greater than the threshold. The threshold may also be updated at a MSC and then sent to the mobile station.