Abstract: The technique of amplifier sharing is implemented in a system designed to accommodate transmit diversity. In one embodiment of the invention, the amplifiers are shared 1) to amplify a first and a second diversity-encoded signal, each of which represents the information a first signal that is to be transmitted using transmit diversity, and 2) to amplify a second signal to be transmitted without using transmit diversity. The first and second diversity-encoded signals are used to form a first and a second composite signal. Each composite signal is amplified in a different one of two power amplifiers. Each amplified composite signal is then used to form an amplified first diversity-encoded signal and an amplified second diversity-encoded signal. The first and second composite signals can also be formed using the second signal. Each composite signal is then amplified in a different one of the two power amplifiers and the two amplified composite signals are used to form an amplified second signal.

Abstract: Improved techniques for characterizing, adjusting and optimizing the overall performance of a wireless network. In an illustrative embodiment, the overall network performance for a particular network configuration is characterized by a vector with two components, one representing network coverage and another representing network capacity. Network coverage is defined by the likelihood of service under load, including interference, and may be further weighted by traffic density. Network capacity is defined by an amount of traffic with a given spatial distribution that can be served at a given overall target-blocking rate. The overall network performance may be characterized using a two-dimensional capacity/coverage diagram which plots overall network performance vectors, each including a network capacity component and a network coverage component, for various network configurations.

Abstract: A signal notching system reduces signal peaks by notching the peak of a signal above a threshold to produce a notched signal. The notched signal is then filtered to produce a resulting signal with a reduced peak amplitude. For example, in an implementation where the signal is represented by signal samples, the peak notching system first locates a peak sample that is beyond a threshold, such as a sample representing a positive peak sample of a peak above the threshold. Once a peak sample is located, the peak notching system adjusts the peak sample by an amount which is a function of the amount that the peak sample is beyond the threshold, effectively creating a notched signal with a one sample notch at the peak. The peak notching system filters the notched signal to fill in the notch to produce a signal with a reduced peak.

Abstract: Techniques for determination of network parameters in, e.g., a processor-implemented system for characterizing, adjusting or optimizing the performance of a wireless network. In an illustrative embodiment, values of one or more link parameters of the wireless network are interpolated along edges in a mesh of data points derived at least in part from road location data characterizing an area serviced by the wireless network. A measure of network performance, e.g., a coverage measure based on pilot signal-to-interference ratio, may be generated using the interpolated values. The edges of the mesh have associated therewith a set of edge weights representative of traffic in the wireless network. The edge weights may be adjusted so as to be in agreement with available network traffic data.

Abstract: A method of producing an amplified signal decomposes a signal into at least a first part and second part using at least one amplitude threshold. The first part includes a portion of the signal with a lower peak-to-average power ratio than the signal based on the amplitude threshold. The second part includes a portion of the signal beyond the amplitude threshold. At least the first part and the second part are amplified to produce an amplified first part and amplified second part, which are combined to produce an amplified signal.

Abstract: Improved techniques for optimizing performance of a wireless network. In an illustrative embodiment, a derivative-based optimization process is applied to optimize an objective function of a network performance metric with respect to a number of network tuning parameter variables. The optimization may be based on first or higher order derivatives of the objective function with respect to the selected network parameter variables. The objective function may include, e.g., one or more of a maximization of network coverage, a maximization of network capacity, and a minimization of network resources. Additional network parameters which are not variables in optimization process serve as constraints to the optimization process. Advantageously, the invention substantially improves the process of designing, adjusting and optimizing the performance of wireless networks.

Abstract: Improved techniques for characterizing, adjusting and optimizing the overall performance of a wireless network. In an illustrative embodiment, the overall network performance for a particular network configuration is characterized by a vector with two components, one representing network coverage and another representing network capacity. Network coverage is defined by the likelihood of service under load, including interference, and may be further weighted by traffic density. Network capacity is defined by an amount of traffic with a given spatial distribution that can be served at a given overall target-blocking rate. The overall network performance may be characterized using a two-dimensional capacity/coverage diagram which plots overall network performance vectors, each including a network capacity component and a network coverage component, for various network configurations.

Abstract: Disclosed is a method and apparatus of transmit diversity that is backward compatible and does not degrade performance using a transmission architecture that incorporates a form of phase sweep transmit diversity (PSTD) referred to herein as split shift PSTD. Split shift PSTD involves transmitting at least two phase swept versions of a signal over diversity antennas, wherein the two phase swept versions of the signal have a different phase. The phase sweep frequency signals may have a fixed or varying phase shifting rate, may have an identical or different phase shifting rate, may be offset from each other and/or may be phase shifting in the same or opposite direction.

Abstract: Described herein is a method and apparatus for transmission that provides the performance of space time spreading (STS) or orthogonal transmit diversity (OTD) and the backwards compatibility of phase sweep transmit diversity (PSTD) without degrading performance of either STS or PSTD using a symmetric sweep PSTD transmission architecture. In one embodiment, a pair of signals s1, and s2 are split into signals s1(a) and s1(b) and signals s2(a) and s2(b), respectively. Signal s1 comprises a first STS/OTD signal belonging to an STS/OTD pair, and signal s2 comprises a second STS/OTD signal belonging to the STS/OTD pair. Signals s1(b) and s2(b) are phase swept using a pair of phase sweep frequency signals that would cancel out any self induced interference. For example, the pair of phase sweep frequency signals utilize a same phase sweep frequency with one of the phase sweep frequency signals rotating in the opposite direction plus an offset of &pgr; relative to the other phase sweep frequency signal.

Abstract: Described herein is a method and apparatus for transmission that provides the performance of space time spreading (STS) or orthogonal transmit diversity (OTD) and the backwards compatibility of phase sweep transmit diversity (PSTD) without significantly degrading performance in additive white guassan noise (AWGN) conditions using a transmission architecture that incorporates STS/OTD and a form of phase sweep transmit diversity (PSTD) referred to herein as biased PSTD, which involves transmitting a signal and a frequency swept version of the same signal over diversity antennas at different power levels to reduce the depths of nulls normally seen in AWGN conditions when regular PSTD is utilized.

Abstract: A method of producing an amplified signal decomposes a signal into at least a first part and second part using at least one amplitude threshold. The first part includes a portion of the signal with a lower peak-to-average power ratio than the signal based on the amplitude threshold. The second part includes a portion of the signal beyond the amplitude threshold. At least the first part and the second part are amplified to produce an amplified first part and amplified second part, which are combined to produce an amplified signal.

Abstract: A signal amplification system involves decomposing a signal into two or more parts, amplifying the parts and then combining the amplified parts to produce the amplified signal. The decomposition can be done such that the resulting parts have characteristics that are amenable to efficient amplification. For example, decomposition of the signal to be amplified can be done using at least one threshold. The first part of the signal to be amplified can be formed by the portion of the signal within the threshold. As such, because the first part forms a signal with a lower PAR, the first part of the signal can be amplified more efficiently than the original signal. The second part of the signal can be formed by the portion of the original signal beyond the threshold. Because the second part is mostly zero, the second part can also be amplified efficiently, for example with a class C type amplifier which does not dissipate any energy when the input signal is zero.

Abstract: The disclosed superconducting multipole RF filter comprises a multiplicity of coupled circular disk resonators designed for operation in the TM 010 mode. The disk resonators are arranged in a co-axial stack, with a circular metal spacer sandwiched between any two neighboring disk resonators. Each metal spacer has a central through-aperture, with a conductive member disposed in the through-aperture and electrically connecting the two neighboring disk resonators that are sandwiching a given metal spacer. A disk resonator comprises two circular members, each circular member comprising a circular dielectric substrate, exemplarily a LaAlO.sub.3 wafer. Superconducting layers (typically YBCO) are disposed on each major surface of the substrate. The two members are joined together such that conductive layers (typically gold) electrically connect the two outside superconducting layers. The disclosed RF filter has good power handling capability, is compact, has good heat removal and relatively simple tuning.

Abstract: The device has a single strip having a first end, a second end, a length and a width. The first end of the strip is curved toward the second end of the strip to form a loop having a height. The length is approximately 10 mm, the width is approximately 5-8 mm, and the height is approximately 0.8-1.2 mm. The loop is preferably fabricated from copper. The loop is mounted directly to a test instrument such as a computer controlled impedance analyzer or network analyzer. The test instrument measures the inductance and resistance of the loop with no thin film sample placed therein, and then measures the inductance and resistance of the loop containing the sample under test. From these measurements, the device ultimately derives the permeability of the sample under test.