摘要:
A position determination system and apparatus for utilizing a network of cellular base stations to determine position of a mobile station includes taking a plurality of statistically independent data measurements of the pilot signals from the base stations. Each of the data measurements includes an earliest time of arrival, providing multiple independent measurements for each of the pilot signals. For each cellular base station, a representative measurement is calculated responsive to the independent measurements, which is used to determine position of the mobile station using an AFLT algorithm and/or in conjunction with a GPS algorithm. In some embodiments, the data measurements for each pilot signal further include an RMSE estimate and time of measurement for each time of arrival, and an energy measurement for all resolvable paths. If the mobile station comprises a cell phone, a cell search list and a GPS search list may be provided by a cell base station.
摘要:
A parameter estimator for estimating one or more parameter(s) from a correlation function derived from a signal using a dynamically variable integration time is described. The parameter estimator may be employed in a subscriber station to estimate the time of arrival of one or more base station or sector pilot signals in a wireless communication system. This information may be utilized in an overall advanced forward link trilateration (AFLT) process for estimating the location of the subscriber station.
摘要:
A position determination system and apparatus for utilizing a network of cellular base stations to determine position of a mobile station includes taking a plurality of statistically independent data measurements of the pilot signals from the base stations. Each of the data measurements includes an earliest time of arrival, providing multiple independent measurements for each of the pilot signals. For each cellular base station, a representative measurement is calculated responsive to the independent measurements, which is used to determine position of the mobile station using an AFLT algorithm and/or in conjunction with a GPS algorithm. In some embodiments, the data measurements for each pilot signal further include an RMSE estimate and time of measurement for each time of arrival, and an energy measurement for all resolvable paths. If the mobile station comprises a cell phone, a cell search list and a GPS search list may be provided by a cell base station.
摘要:
A parameter estimator for estimating one or more parameter(s) from a correlation function derived from a signal using a dynamically variable search window is described. The parameter estimator may be employed in a subscriber station to estimate the time of arrival of one or more base station pilot signals in a wireless communication system. This information may be utilized in an overall advanced forward link trilateration (AFLT) process for estimating the location of the subscriber station.
摘要:
A parameter estimator for estimating one or more parameter(s) from a correlation function derived from a signal using a dynamically variable integration time is described. The parameter estimator may be employed in a subscriber station to estimate the time of arrival of one or more base station or sector pilot signals in a wireless communication system. This information may be utilized in an overall advanced forward link trilateration (AFLT) process for estimating the location of the subscriber station.
摘要:
A parameter estimator for estimating one or more parameter(s) from a signal is described. A correlation function is derived from the signal, and the correlation function analyzed to determine if one or more first peak(s) are present, and, if so, distinguishable from the sidelobe(s) of a second peak. If the one or more first peak(s) are present and distinguishable from the sidelobe(s) of the second peak, the one or more parameter(s) are estimated from the one or more first peak(s). If the one or more first peak(s) are not present, or, if present, are not distinguishable from the sidelobe(s) of the second peak, the one or more parameter(s) are estimated from the second peak. The parameter estimator may be employed in a subscriber station to estimate a parameter such as the time of arrival of one or more base station or sector pilot signals in a wireless communication system. This information may be utilized in an overall advanced forward link trilateration (AFLT) process for estimating the location of the subscriber station.
摘要:
Wireless receiver circuits and methods include algorithms for switching between a least-squares/minimum mean-square error method of channel estimation known as the CE algorithm, and a continuous plot method of channel estimation known as the CPCE algorithm based upon channel characteristics to improve reception of wireless communications in different reception conditions. In an embodiment, the CPCE algorithm may be selected by a processor for use in channel estimation when a calculated number of candidate paths is less than or equal to a first threshold value, a calculated power ratio of the L strongest paths to the total of all paths is greater than or equal to a second threshold value, and the maximum Automatic Gain Control variation is greater than or equal to a third threshold value. Threshold values may be based on field testing, and set to values at which the CE or CPCE algorithm exhibits better performance.
摘要:
Apparatus and methods for QAM modulation are disclosed using dual polar modulation. QAM modulation of a signal is accomplished by translating a QAM signal into two phasors having the same or constant amplitude and then phase shifting one of the phasor by 180 degrees for a differential load. The phasors are then polar modulated such that, when differentially combined in the load through summation or superposition, a QAM modulated symbol results. The use of constant amplitude phasors when power amplified for transmission of QAM modulated signals allows amplifiers to be operated in a saturation mode with greater efficiency than conventional amplifiers used in QAM modulation, which operate in a less efficient linear mode to effect amplitude modulation. Additionally, differential combining of the phasors affords relaxation of the turns of a transformer used in amplifying the phasors.
摘要:
Methods, systems, devices, and apparatuses for signal condition of polar transmitters are discussed this patent application. According to one embodiment, a frequency limiting mechanism for a polar transmitter can perform minimal distortion frequency limiting to comply with the polar transmitter requirements while meeting emissions specifications. Embodiments of the present invention may be utilized as features or components of wireless communication devices to enable minimal distortion to information carrying signals and to meet emissions specifications. Other aspects, embodiments, and features are claimed and discussed above.
摘要:
For position determination with peer-to-peer communication, a target terminal broadcasts a request for assistance in determining its position. At least one ranging terminal receives the request. Each ranging terminal sends a response with a time of arrival (TOA) measurement for the request and the position of the ranging terminal. For two-way peer-to-peer, the target terminal receives at least one response from the at least one ranging terminal, obtains a TOA measurement for each response, estimates the distance to each ranging terminal based on the TOA measurement for the request and/or the TOA measurement for the response, and computes a position estimate for itself based on the estimated distance and the position for each ranging terminal. For one-way peer-to-peer, a network entity receives at least one response from the at least one ranging terminal, computes a position estimate for the target terminal, and sends the position estimate to the target terminal.