Abstract: A configurable multimode despreader for spread spectrum applications is disclosed herein. The despreader includes a plurality of data lines, at least one selective coupler coupled to the plurality of data lines, at least one multiplier coupled to the selective coupler, and a code input line coupled to the multiplier. The selective coupler selectively couples one of the plurality of data lines with the multiplier per any one of a plurality of despreading protocols. The multiplier then multiplies a desired input data type received from the selective coupler with a despreading code chip received from the code input line to produce an observation. The programmable multimode despreader supports variable code and data modulation schemes and variable spreading factors.

Abstract: A method of profiling disparate communications and signal processing standards. The method begins with selection of a set of communications and signal processing standards for analysis. Next, functions performed by the set of communications and signal processing standards are identified and ranked according to computational intensity. A set of high computational intensity functions are then selected for implementation as kernels, the set of kernels forming a programmable processor that enables implementation of any one of the set of communications and signal processing standards.

Abstract: A digital wireless communication device comprises a software-programmable processor, a heterogeneous reconfigurable multiprocessing logic circuit, and a bus connecting the software-programmable processor and the heterogeneous reconfigurable multiprocessing logic circuit. The heterogeneous reconfigurable multiprocessing logic circuit comprises a set of heterogeneous signal processing kernels and a reconfigurable data router interconnecting the heterogeneous signal processing kernels. The software-programmable processor is selected from the group comprising: a digital signal processor and a central processing unit. The architecture provides the ability to reconfigure a single product platform for multiple standards, applications, services, and quality-of service, instead of developing multiple hardware platforms to establish the same collective functionality.

Abstract: A method of generating a configuration for a configurable spread spectrum communication device is disclosed herein. The method, implemented on a computing device having a processor and a computer readable memory, starts with a first step of receiving an input identifying a desired function, and a desired operation within the desired function, to be implemented by a configurable communication device. In a subsequent step, a signal flow path for the desired operation is generated by the computing device. Next, the desired operation is mapped onto a computing element within the configurable communication device; the computing element having localized control and being function-specific. The aforementioned steps are repeated to satisfy multiple operations required to enable the desired function.

Abstract: A monolithic CMOS programmable digital intermediate frequency receiver includes a programmable memory, a clock generator, a sigma delta converter, a digital downconverter, and a decimation filter network. The programmable memory receives and stores a first value representative of a programmable parameter k and a second value representative of programmable parameter N. Coupled to the programmable memory, the clock generator generates a first clock signal, a second clock signal and a third clock signal. The first clock signal has a first frequency, fl, the second clock signal has a second frequency approximately equal to fl/k and the third clock signal has a third frequency approximately equal to fl/N. The sigma delta converter samples an analog input signal having an intermediate frequency using the first clock signal to generate a first set of digital signals. The digital downconverter mixes down the first set of digital signals using the second clock signal to generate a second set of digital signals.

Abstract: A rake receiver in accordance with an exemplary embodiment of this invention is configurable by an external agent (e.g., microcontroller, DSP, or state machine) to suit the particular requirements of different spread spectrum systems. In an exemplary embodiment, the receiver includes multiple fingers. Each finger includes a plurality of generic despreaders/descramblers, a plurality of generic dechannelizers coupled to the despreaders/descramblers, and at least one timing estimation controller coupled to the despreaders/descramblers. The finger also includes at least one phase estimation controller, at least one frequency estimation controller, and at least one energy estimation controller all coupled to the generic dechannelizers.

Abstract: An efficient software download to a configurable communication device is disclosed herein. The method of efficiently downloading software begins with a step of receiving a request to configure a communication device to run a communication application. The communication device being configured has a plurality of function blocks with a fixed portion of hardware and a flexible portion of hardware, wherein the same plurality of function blocks is capable of operating a plurality of communication applications. In a next step, the capability of the fixed portion and the flexible portion of hardware of the communication device is evaluated for a capability of implementing the communication application. Next, configuration information only for the flexible portion of hardware of the communication device is transmitted to the communication device to enable it to operate the communication application.

Abstract: A wireless spread spectrum communication platform for processing a communication signal is disclosed herein. The wireless communication platform includes a first computing element, a second computing element, and a reconfigurable interconnect. The first computing element is coupled to the second computing element via the reconfigurable interconnect. A design configuration of the first computing element is heterogeneous with respect to a design configuration of the second computing element. The reconfigurable interconnect has an uncommitted architecture, thereby allowing it to be configured by an outside source to couple portions of the first reconfigurable interconnect with portions of the second reconfigurable interconnect in a variety of combinations. The first computing element, the second computing element, and the reconfigurable interconnect operable to perform discrete functions suitable for processing of the communication signal.

Abstract: An apparatus for digitally processing signals within wireless communications basestations which includes a channel pooling signal processor and a digital signal processor. The channel pooling signal processor includes a plurality of computation units typically realized in a heterogeneous multiprocessing architecture, a test interface for testing the function of the plurality of the computation units, a general-purpose microprocessor for managing the dataflow into and out of the channel pooling signal processor as well as effecting the control and configuration of the computation units, and an interconnect mechanism for connecting the plurality of computation units to the input, output, test interface, and the general-purpose microprocessor.

Abstract: A rake receiver in accordance with an exemplary embodiment of this invention is configurable by an external agent (e.g., microcontroller, DSP, or state machine) to suit the particular requirements of different spread spectrum systems. In an exemplary embodiment, the receiver includes multiple fingers. Each finger includes a plurality of generic despreaders/descramblers, a plurality of generic dechannelizers coupled to the despreaders/descramblers, and at least one timing estimation controller coupled to the despreaders/descramblers. The finger also includes at least one phase estimation controller, at least one frequency estimation controller, and at least one energy estimation controller all coupled to the generic dechannelizers.

Abstract: A wireless TDMA communication platform for processing a communication signal is disclosed herein. The platform includes a sampler for sampling a TDMA signal, received from a transmission channel; a derotator for correcting for frequency offset in the sampled TDMA signal; a matched filter for correcting for the response of the transmission channel in the received TDMA signal; an equalizer to which is applied an output signal from the matched filter; a deinterleaver to deinterleave the received TDMA signal; and a channel decoder for decoding the received TDMA signal after it is deinterleaved.

Abstract: A configurable all-digital coherent demodulator system for spread spectrum digital communications is disclosed herein. The demodulator system includes an extended and long code demodulator (ELCD) coupled to a traffic channel demodulator (TCD) and a parameter estimator (PE). The demodulator also includes a pilot assisted correction device (PACD) that is coupled to the PE and the TCD. The ELCD provides a code-demodulated signal to the TCD and the PE. In turn, the TCD provides a demodulated output data signal to the PE. The PACD corrects the phase error of the demodulated output data based on an error estimate that is fed forward from the PE. Accumulation operations in the ELCD, TCD, and PE are all programmable. Similarly, a phase delay in the PACD is also programmable to provide synchronization with the error estimate from the PE.

Abstract: A configurable multimode despreader for spread spectrum applications is disclosed herein. The despreader includes a plurality of data lines, at least one selective coupler coupled to the plurality of data lines, at least one multiplier coupled to the selective coupler, and a code input line coupled to the multiplier. The selective coupler selectively couples one of the plurality of data lines with the multiplier per any one of a plurality of despreading protocols. The multiplier then multiplies a desired input data type received from the selective coupler with a despreading code chip received from the code input line to produce an observation. The programmable multimode despreader supports variable code and data modulation schemes and variable spreading factors.

Abstract: A method of generating a configuration for a configurable spread spectrum communication device is disclosed herein. The method, implemented on a computing device having a processor and a computer readable memory, starts with a first step of receiving an input identifying a desired function, and a desired operation within the desired function, to be implemented by a configurable communication device. In a subsequent step, a signal flow path for the desired operation is generated by the computing device. Next, the desired operation is mapped onto a computing element within the configurable communication device; the computing element having localized control and being function-specific. The aforementioned steps are repeated to satisfy multiple operations required to enable the desired function.

Abstract: A method of optimally positioning an imaging device comprising the steps of storing a reference image; continuously obtaining an acquired view with the imaging device; determining whether the imaging device is in an optimal position by periodically comparing the acquired image with the reference image; and adjusting the position of the imaging device if the imaging device is not in an optimal position.

Abstract: DC offset cancellation and timing recovery is provided in a homodyne receiver. The homodyne receiver demodulates an RF signal to produce a baseband signal. An initial offset correction module determines an initial DC offset of the baseband signal. An initial offset correction is applied to the baseband signal to provide an initial corrected baseband signal. Wherein, a dynamic DC offset correction module determines a dynamic DC offset. A dynamic DC offset correction is applied to the initial corrected baseband signal providing a dynamic corrected baseband signal. A timing signal is acquired from the baseband signal for synchronizing the receiver to a transmitter. A method for correcting DC offset of a baseband signal in a homodyne receiver is also described.

Abstract: In a digital wireless communication system operating between a first unit and a second unit, the first unit transmits a digitally encoded RF signal at a first frequency in a plurality of a non-contiguous time slots to the second unit. The second unit receives the digitally encoded RF signals. The received RF digitally encoded signal is converted to an intermediate frequency (IF). An A to D converter samples the received IF digitally encoded signals and generates a plurality of discrete binary symbols during one of the plurality of non-contiguous time slots. A phase error signal is generated for each one of the plurality of discrete binary symbols. A frequency error signal is generated for the subsequent symbol in accordance with .DELTA.f(n+1)=.DELTA.f(n)+g.sub.1 (.crclbar.(n)-.crclbar.(n)). The conversion of the RF signal to intermediate frequency is controlled in response to the frequency error signal.

Abstract: An intermediate frequency (IF) to baseband frequency signal converter for decoding an analog IF signal using phase information contained in the IF signal includes a first signal generator for generating an analog square wave signal from the IF signal. The signal converter also includes a second signal generator for generating a local phase reference signal, and a phase difference determinator for determining at a particular sampling interval a phase difference between a phase of the analog square wave signal and a phase of the local phase reference signal, wherein the phase difference represents a symbol which the signal converter has decoded from the IF signal.

Abstract: In a digital wireless communication system communicating between a mobile unit and a stationary unit, a received digitally encoded signal is sampled to produce a first sampled digital signal having a plurality of symbols. The short term energy over a plurality of a contiguous symbols is measured. The short term energy symbol over a first plurality of a contiguous short term energy points is measured. The short term energy average over a second plurality of contiguous short term energy points is measured. The second plurality of contiguous short term energy points is spaced apart from the first plurality of contiguous short term energy points. The difference between the first short term energy average and the second short term energy average is calculated to derive an estimate of the speed of the mobile unit relative to the base unit.

Abstract: A spread spectrum receiver for use in spread spectrum communication systems is disclosed. The spread spectrum receiver of the present invention includes an analog-to-digital converter for receiving an analog spread spectrum signal, and for converting the received analog signal to a digital signal. The spread spectrum receiver also includes a digital frequency offset correction device, for modifying the digital signal in accordance with a frequency correction term signal to thereby correct for frequency offset in the received analog signal. The spread spectrum receiver also contains a Rake receiver. The spread spectrum receiver searches through the modified digital signal to identify M of the main and multipath return signals having the strongest signal strengths.