摘要:
The present invention relates to synchronization circuitry that is used to synchronize an asynchronous received RF message with a transmitted RF message. In one embodiment of the present invention, the synchronization circuitry includes at least one counter, which is used to associate timing of the asynchronous received RF message with a receive count value, and associate timing of the transmitted RF message with a transmit count value. A time delay between occurrence of the receive count value and the transmit count value provides accurate timing for the start of the transmitted RF message.
摘要:
Disclosed is a coordinate rotation digital computer (CORDIC) having a maximum value circuit that selects a larger of the first component or the second component. A minimum value circuit selects a minimum operand that is a smaller one of the first component or the second component. Also included are N rotator stages, each corresponding to a unique one of N predetermined vectors, each of the N rotator stages having a first multiply circuit to multiply the maximum operand by a cosine coefficient of a predetermined vector to output a first rotation component, a second multiply circuit for multiplying the minimum operand by a sine coefficient of the predetermined vector to output a second rotation component, and an adder circuit for adding the first rotation component to the second rotation component to output one of N results, and a maximum value circuit for outputting a maximum one of the N results.
摘要:
The present invention relates to synchronization circuitry that is used to synchronize an asynchronous received RF message with a transmitted RF message. In one embodiment of the present invention, the synchronization circuitry includes at least one counter, which is used to associate timing of the asynchronous received RF message with a receive count value, and associate timing of the transmitted RF message with a transmit count value. A time delay between occurrence of the receive count value and the transmit count value provides accurate timing for the start of the transmitted RF message.
摘要:
An RF transmitter that, during a transmission session, transmits multiple data slices, which are synchronized to each other by a transmit counter. Typically, the time between transmission of consecutive data slices is constant; however, to synchronize the transmission session with a base station, the time between transmission of consecutive data slices may be occasionally adjusted. By using the transmit counter to synchronize data transmissions, effects of uncompensated latencies or variances in latencies may be reduced or eliminated.
摘要:
The present invention relates to estimating a direct current (DC) offset of a radio frequency (RF) receiver when an estimated amplitude of a continuous-transmission amplitude-modulated (AM) RF signal is below a first threshold and when the RF receiver is not receiving an RF input signal. The estimated DC offset of the RF receiver may be used to improve RF receiver performance, particularly over temperature and supply voltage variations. Estimating the DC offset of the RF receiver when the estimated instantaneous amplitude of the continuous-transmission AM RF signal is below the first threshold may minimize errors in the estimated DC offset.
摘要:
Disclosed is a coordinate rotation digital computer (CORDIC) having a maximum value circuit that selects a larger of the first component or the second component. A minimum value circuit selects a minimum operand that is a smaller one of the first component or the second component. Also included are N rotator stages, each corresponding to a unique one of N predetermined vectors, each of the N rotator stages having a first multiply circuit to multiply the maximum operand by a cosine coefficient of a predetermined vector to output a first rotation component, a second multiply circuit for multiplying the minimum operand by a sine coefficient of the predetermined vector to output a second rotation component, and an adder circuit for adding the first rotation component to the second rotation component to output one of N results, and a maximum value circuit for outputting a maximum one of the N results.
摘要:
An arrangement and method for discontinuous software FDD monitoring during TDD call allows removal of a conventional external notch filter in a dual mode WCDMA and PCS/DCS handset. The WCDMA RX frame is allowed to have a few slots corrupted by the PCS/DCS transmitter noise during DCS transmission, and a scheme is used to recover the required information by not considering the corrupted slots. Due to the fact that during WCDMA FDD RX monitoring, the processing required is performed in stages, and since the information that is measured during a WCDMA frame is repeated in every frame, the scheme of the invention is based on the idea that if a given slot is corrupted in a WCDMA frame, in the next WCDMA frame the slot will be no more corrupted due to the difference in timing between the PCS/DCS transmitter protocol and the WCDMA timing protocol.
摘要:
An arrangement and method for discontinuous software FDD monitoring during TDD call allows removal of a conventional external notch filter in a dual mode WCDMA and PCS/DCS handset. The WCDMA RX frame is allowed to have a few slots corrupted by the PCS/DCS transmitter noise during DCS transmission, and a scheme is used to recover the required information by not considering the corrupted slots. Due to the fact that during WCDMA FDD RX monitoring, the processing required is performed in stages, and since the information that is measured during a WCDMA frame is repeated in every frame, the scheme of the invention is based on the idea that if a given slot is corrupted in a WCDMA frame, in the next WCDMA frame the slot will be no more corrupted due to the difference in timing between the PCS/DCS transmitter protocol and the WCDMA timing protocol.
摘要:
The present invention relates to estimating a direct current (DC) offset of a power detection circuit when an estimated instantaneous amplitude of a continuous-transmission amplitude-modulated (AM) radio frequency (RF) signal is below a first threshold. The power detection circuit may be used to estimate an average output power associated with the continuous-transmission AM RF signal. The estimated average output power may be used as part of a feedback system to regulate the average output power. The estimated DC offset of the power detection circuit may be used to improve the estimate of the average output power, particularly over temperature and supply voltage variations. Estimating the DC offset of the power detection circuit when the estimated instantaneous amplitude of the continuous-transmission AM RF signal is below the first threshold may minimize errors in the estimated DC offset.
摘要:
A system and method are provided for quickly measuring the Root Mean Square (RMS) value of digital quadrature signals (I, Q) input to a Wideband Code Division Multiple Access (W-CDMA) transmitter. In general, in a W-CDMA transmitter such as that in a Universal Mobile Telecommunications System (UMTS), multiple channels are combined to provide the digital quadrature signal (I, Q) input to the transmitter. The RMS value of the digital quadrature signal (I, Q) may be determined using a number of consecutive samples of the digital quadrature signal (I, Q) over a period corresponding to mutually orthogonal segments of the spreading codes used for the transmitted channels. As a result of the mutual orthogonality of the segments of the spreading codes, a residual error of the RMS measurement is equal to zero, thereby providing an accurate RMS measurement in much less time than required by traditional RMS measurement schemes.