Abstract: The receiver captures an electromagnetic transmission carrying a bauded signal, such as a transmission from an orbiting satellite, and processes it for Doppler shift analysis. The electromagnetic transmission is captured and a non-linear operation is performed to expose a cyclostationary feature of the captured transmission that will define a rate-line. This rate-line will exist at a frequency that is related to the bauded signal and Doppler shift relative to the motion of the transmitter to the receiver. The rate-line frequency is tracked in time to generate data indicative of a Doppler shift associated with the satellite and processed by an estimator fed by satellite propagator to supply positioning, navigation and timing services at the receiver output.

Abstract: An electromagnetic transmission carrying a bauded signal, such as a transmission from an orbiting satellite, is processed for Doppler shift analysis. The electromagnetic transmission is captured and a non-linear operation is performed to expose a cyclostationary feature of the captured transmission that defines a rate-line having a rate-line frequency that is related to the bauded signal and to the motion of the transmitter relative to the receiver. The rate-line frequency is tracked in time to generate data indicative of Doppler shift associated with the satellite. The data are then supplied to a tracking receiver.

Abstract: An electromagnetic transmission carrying a bauded signal, such as a transmission from an orbiting satellite, is processed for Doppler shift analysis. The electromagnetic transmission is captured and a non-linear operation is performed to expose a cyclostationary feature of the captured transmission that defines a rate-line having a rate-line frequency that is related to the bauded signal and to the motion of the transmitter relative to the receiver. The rate-line frequency is tracked in time to generate data indicative of Doppler shift associated with the satellite. The data are then supplied to a tracking receiver.

Abstract: The receiver captures an electromagnetic transmission carrying a bauded signal, such as a transmission from an orbiting satellite, and processes it for Doppler shift analysis. The electromagnetic transmission is captured and a non-linear operation is performed to expose a cyclostationary feature of the captured transmission that will define a rate-line. This rate-line will exist at a frequency that is related to the bauded signal and Doppler shift relative to the motion of the transmitter to the receiver. The rate-line frequency is tracked in time to generate data indicative of a Doppler shift associated with the satellite and processed by an estimator fed by satellite propagator to supply positioning, navigation and timing services at the receiver output.

Abstract: Disclosed herein are various embodiments of methods, systems, and apparatuses for sending and receiving signals in a digital communication system. In one embodiment performs steps of transmitting a signal from a device with a first antenna array and calibrating the signal with a phase shift of the signal. In one exemplary method embodiment, a signal is transmitted from a beam-forming transmitter to an assisting receiver in an IEEE 802.11 wireless transmission. A return calibration signal from the assisting receiver with information regarding the phase error of signal is received by the beam-forming transceiver. The beam-forming transmitter introduces a calibration phase error to cancel the phase error as reported by the assisting receiver.

Abstract: An ophthalmic surgical system 10 includes an aspiration device 12 for aspirating fluids and tissue from a surgical site 14, and a surgical handpiece 16 for performing a surgical function. A control unit 46 is connected to each of the aspiration device and the surgical handpiece for controlling the operation of each device and handpiece. A user interface 48 forming a portion of the control unit 46, guides a user by prompting the user to answer a series of questions and the control unit, controls the devices and handpieces based on the user's answers.

Abstract: An on-signal calibration system I and Q signals of a transmitter to remove distortions in the RF output signal. The transmitter generates I and Q values and converts, modulates and combines the I and Q values into the RF output signal for transmission. The calibration system includes a detector, a sampler, a selector, an imbalance estimator, and an IQ corrector. The detector senses the RF output signal and provides a detection signal indicative thereof. The sampler samples the detection signal and provides digital samples. The selector selects from among the digital samples that correspond to predetermined ranges of the I and Q values, or otherwise predetermined selection boxes at predetermined phases. The imbalance estimator determines at least one imbalance estimate based on selected digital samples. The IQ corrector corrects the I and Q values using at least one imbalance estimate.