318 results about "Envelope detector" patented technology

Methods and systems for power control with optimum power efficiency with a multi-port distributed antenna are disclosed and may include selectively enabling one or more power amplifiers (PAs) coupled to the antenna. The selective enabling may be based on a desired output power radiated from the antenna, and the PAs may be coupled to ports on the antenna based on an output impedance of the PAs and a characteristic impedance of the ports. Each of the PAs may be configured for maximum efficiency in different power ranges. The power ranges may be inversely proportional to the output impedance of the PAs. The output power may be monitored utilizing a power detector, such as an envelope detector, coupled to the antenna. The antenna may be integrated on a chip with the one or more PAs or may be located external to the chip. The antenna may include a microstrip antenna.

An M code envelope detector receives an incoming binary offset carrier (BOC) signal, such as the M code signal, and generates inphase BOC and quadraphase BOC signals, separated by an offset, that have respective ambiguous correlation envelopes, that when combined, provide a near unimodal correlation function with respect to code phase error of the BOC signal having an inherent multimodal autocorrelation function, with the near unimodal correlation envelope being tracked by early and late code replicas at broad one chip phases for providing unambiguous but nonlinear code phase error tracking, which detector is then further improved with the use of code replicas having narrow partial chip phases, such as ⅛ chip phases, for providing near linear code phase error tracking for unambiguous and accurate code tracking of the BOC signal.

An embodiment of the invention is a predistortion approach to linearize a power amplifier without frequency conversion of the RF signals by using envelope and phase detectors to detect the error to be corrected, and then one or more analog multiplier(s) and a DSP-based processor. For the analog embodiment, the inherent nature of the analog circuitries allows digital predistortion processing structured directly at the RF band, and enables a single power amplifier to support multi-modulation schemes, multi-carriers and multi-channels. As a result, the predistortion architecture is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems. The wireless system performance can be improved and upgraded just by using the new PA module rather than change or rebuild new subsystem in existing base station. The analog embodiment can also mix and match its analog multipliers with other analog components such as phase splitters, phase shifters, attenuators, filters, couplers, mixers, low-noise amplifiers, buffers, envelope detectors, and etc., to provide additional features.