Class / Patent application number | Description | Number of patent applications / Date published |
455114100 | Having harmonic radiation suppression | 11 |
20090036068 | WIRELESS SYSTEM HAVING HIGH SPECTRAL PURITY - A wireless system having high spectral purity output signals. The wireless system has a transmitter circuit for transmitting an output signal and a power amplifier for amplifying the output signal for wireless transmission via an antenna. Positioned in-line with the output signal between the transmitter circuit and the power amplifier is a harmonic trap configured for inhibiting harmonics within a predetermined frequency range generated by the power amplifier from leaking into the transmitter circuit. The harmonic trap can be implemented as a discrete device, or integrated within the transmitter circuit or integrated within the power amplifier. By inhibiting the harmonics from leaking into the transmitter circuit, degraded performance of the transmitter circuit is prevented. | 02-05-2009 |
20090143031 | Harmonic suppression mixer and tuner - A harmonic suppression mixer for down converting an RF signal to a complex I and Q baseband signal that uses a plurality of switching mixers each with a gain stage to produce a sinusoidal weighted sum of the mixer outputs. Odd harmonics output by each switching mixer is suppressed in the composite signal. A low skew local oscillator (LO) clock generator creates multiple LO phases and drives the mixers. The mixer can be used in low noise direct conversion RF tuners. The mixer is configurable by programming gain stage coefficient values to achieve a variable number of effective mixers used in combination. At low tuning frequencies, all available mixers are programmed with unique coefficients and driven by different LO clock phases to achieve maximum harmonic suppression. At high tuning frequencies, some mixers are paralleled and duplicate coefficients are programmed or mixers are disabled to reduce the number of effective mixers. | 06-04-2009 |
20090280757 | MOBILE WIRELESS COMMUNICATIONS DEVICE WITH REDUCED HARMONICS RESULTING FROM METAL SHIELD COUPLING - A mobile wireless communications device includes a housing and antenna supported by the housing. At least one circuit board is carried by the housing and has radio frequency (RF) circuitry operative with the antenna for receiving and transmitting RF signals through the antenna. A power amplifier is connected within a transmission line for amplifying RF signals to be transmitted over the transmission line to the antenna. An antenna switch is carried by the circuit board and connected to the antenna and RF circuitry. An RF shield surrounds the power amplifier and antenna switch isolates the power amplifier and antenna switch from the antenna and RF circuitry. A low pass filter has an input connected to the power amplifier and an output connected to the antenna switch for reducing any RF coupling of voltage standing waves of upper harmonic frequencies from the power amplifier into the antenna switch between the input and output of the low pass filter through the RF shield while maintaining transmission of signals through the transmission line at a desired fundamental frequency. | 11-12-2009 |
20100112965 | Method and Apparatus to Transmit, Receive and Process Signals with Narrow Bandwith Devices - In a representative embodiment, an electronic transmitter comprises a signal source configured to provide an input signal comprising a plurality of frequency components; and a plurality of transducers each configured to receive the input signal and each configured to resonate substantially at one frequency of a subset of the plurality of frequency components. An electronic receiver, an acoustic transmitter and an acoustic receiver are also described. | 05-06-2010 |
20120171973 | SYSTEMS AND METHODS FOR IMPLEMENTING A HARMONIC REJECTION MIXER - Various embodiments of systems and methods for generating local oscillator (LO) signals for a harmonic rejection mixer are provided. One embodiment is a system for generating local oscillator (LO) signals for a harmonic rejection mixer. One such system comprises a local oscillator, a divide-by-N frequency divider, a divide-by-three frequency divider, and a harmonic rejection mixer. The local oscillator is configured to provide a reference frequency signal. The divide-by-N frequency divider is configured to divide the reference frequency signal by a value N and provide an output signal. The divide-by-three frequency divider is configured to receive the output signal of the divide-by-N frequency divider and divide the output signal into three phase-offset signals. The harmonic rejection mixer is configured to receive the three phase-offset signals and eliminate third frequency harmonics. | 07-05-2012 |
20130309984 | HIGH-FREQUENCY SWITCH MODULE - A low pass filter connected between an individual port of a switch device and a high-frequency switch module attenuates the second harmonic and the third harmonic of a transmission signal input to a first transmission signal input terminal. Further, the inductances/capacitances of inductors and capacitors defining the low pass filter are set such that the phase of a harmonic signal generated by a power amplifier is different by 180° from the phase of a harmonic signal produced as a result of the low pass filter shifting the phase of a harmonic signal generated due to distortion in a switch device, in an end portion on the first transmission signal input terminal side. | 11-21-2013 |
20140030990 | Methods and Circuits for Detuning a Filter and Matching Network at the Output of a Power Amplifier - In transmitter modules or power amplifier (PA) modules there is at least a possible path for a second and even a third harmonic of a low band to crossover unfiltered into the high band path and reach the antenna and hence cross band isolation is necessary. Forward isolation is necessary in order to limit the input crossing over the PAs into the antenna port. According to the methods and the circuits such cross band isolation and forward isolation is improved by detuning the filter and matching network at the output of the PA. The circuit comprises a trap at the harmonic frequencies of the low band thereby at least reducing the impacts of the cross band and forward isolation. | 01-30-2014 |
20140065988 | FREQUENCY-MULTIPLIED HARMONIC SUPRESSION METHOD FOR RF CIRCUIT - A frequency-multiplied harmonic suppression RF circuit design method includes the steps of defining respective operating frequencies of predetermined major electronic components of the RF circuit to be designed, using these operating frequencies to calculate the values of respective frequency-multiplied harmonics and intermodulation distorsions, designing respective filters subject to the values of the frequency-multiplied harmonics and intermodulation distorsions obtained, calculating the locations of the frequency-multiplied harmonics in the RF circuit under design, installing the designed filters in the calculated locations, and testing and adjusting the installed filters. | 03-06-2014 |
20140155005 | MOBILE WIRELESS COMMUNICATIONS DEVICE WITH REDUCED HARMONICS RESULTING FROM METAL SHIELD COUPLING - A mobile wireless communications device includes a housing, antenna, and circuit board carried by the housing and having radio frequency (RF) circuitry operative with the antenna for receiving and transmitting RF signals through the antenna. A power amplifier is connected within a transmission line for amplifying RF signals to be transmitted over the transmission line to the antenna. An antenna switch is connected to the antenna and RF circuitry. An RF shield surrounds the power amplifier and antenna switch and isolates the power amplifier and antenna switch from the antenna and RF circuitry. A low pass filter is connected to the power amplifier and antenna switch for reducing any RF coupling of voltage standing waves of upper harmonic frequencies from the power amplifier into the antenna switch through the RF shield while maintaining transmission of signals through the transmission line at a desired fundamental frequency. | 06-05-2014 |
20150094004 | HARMONIC REJECTIVE PASSIVE UP CONVERTER - Methods and apparatuses are presented for harmonic reject upconverting a baseband signal using at least one quadrature passive upconversion mixer. In some embodiments, an apparatus may include a first quadrature passive mixer configured to receive a first baseband input and a first LO input, and a second quadrature passive mixer configured to receive a second baseband input and a second LO input. A first output of said first passive mixer may be directly connected to a first output of said second passive mixer and together coupled to a first amplifier input. A second output of said first passive mixer may be directly connected to a second output of said second passive mixer and together coupled to a second amplifier input. The transmitter may be configured to output an upconverted signal with at least one rejected harmonic spurious mixing product based on the first and second amplifier inputs. | 04-02-2015 |
20150126140 | WIRELESS TRANSMITTER - A wireless transmitter for resolving gain mismatch of TV band is disclosed. In one embodiment, a wireless transmitter comprises a two-stage 14-path harmonic-rejection mixer to manage harmonic rejection ratio in lower sub-bands, and a two-stage 6-path harmonic-rejection mixer to manage harmonic rejection ratio in upper sub-bands. The gain mismatch is resolved by selecting gain ratios of the first and the second stage of the two-stage 14-path harmonic-rejection mixer and the two-stage 6-path harmonic-rejection mixer. | 05-07-2015 |