摘要:
Methods and apparatuses for quiet spot detection for radio frequency transmission thereon. According to various embodiments, a device may include a local receiver configured to evaluate one or more frequencies of a frequency band to determine a quiet spot frequency, the device further including a local transmitter configured to transmit signals at the quiet spot frequency.
摘要:
Embodiments of the present disclosure provide a device comprising a receiver port configured to be operatively coupled to a local receiver antenna; a transmitter port configured to be operatively coupled to a local transmitter antenna and to receive signals received by the local transmitter antenna at least for a portion of time while the local receiver antenna is not operatively coupled to the receiver port; and a quiet spot determination unit configured to receive signals received by the local receiver antenna at least for a portion of time while the local receiver antenna is operatively coupled to the receiver port, receive signals received by the local transmitter antenna at least for the portion of time while the local receiver antenna is not operatively coupled to the receiver port, and determine a quiet spot frequency. Other embodiments are also described and claimed.
摘要:
Methods and apparatuses for quiet spot detection for radio frequency transmission thereon. According to various embodiments, a device may include a local receiver configured to evaluate one or more frequencies of a frequency band to determine a quiet spot frequency, the device further including a local transmitter configured to transmit signals at the quiet spot frequency.
摘要:
The present invention relates to a flat-running device intended for being fitted on an assembly mounted on a tubeless one-piece rim for an automobile, said mounted assembly including said device, and to a method for mounting and/or removing said mounted assembly. The device according to the invention (1) includes a ring (2) with a radially internal mounting surface for the device, intended to closely match the hollow section of the rim (11), the ring having an open structure with two ends held closely facing one another by a means (5) for clamping the ring. According to the invention, at least one transverse notch (6), the two edges and the bottom of which are located under one of the ends of the ring, is formed in at least one of said side portions (3a), forming a circumferential lip which projects axially from the corresponding side wall of the ring, which includes said recess and is suitable for wedging the ring in the hollow section of the rim, such as to enable, via said notch, transverse insertion of a tool (7) such as a lever between the rim and said mounting surface in order to facilitate the operations of mounting and/or removing the device on the rim.
摘要:
An arrangement (100) and method for sigma-delta analog-to-digital conversion by providing parallel translating sigma-delta analog-to-digital converters (21, 22) and summing their outputs to produce a digital output signal having a bandwidth greater than that of the first or second translating sigma-delta analog-to-digital converters (21, 22). The parallel translating sigma-delta analog-to-digital converters (21, 22) use switching sequences arranged to cancel third and fifth harmonics in the digital output signal. Orthogonality error in the switching sequences applied to the sigma-delta modulators is compensated by adjusting the phase of the signals applied to mixers (51, 52).
摘要:
A Multi-Rate Analog-to-Digital Converter (19) is coupled to a single crystal oscillator (17) as a reference clock and has at least two separate channels arranged to sample and convert input data at two differing clock rates. Each channel derives a clock signal from the reference clock. Associated with each of the channels is a Sigma-Delta converter (10a, 10b) comprising a modulator (12), a filter (14) and a resampler (18). The modulator (12) receives input data and provides a data signal to the filter (14), which itself provides a filtered data signal to the associated data resampler. The data resampler resamples the data and provides a digital output signal. As there is sampling in the digital domain the advantages associated with signal processing, speed and low noise injection are obtained. Similarly as the output of the modulator (12) is in digital form, it can be manipulated and processed readily and with the existing software.
摘要:
A controller in a receiver monitors RSSI and AGC gain levels to determine signal conditions and adjust filter performance accordingly to optimize power consumption while providing acceptable signal quality. When RSSI level is high and AGC gain is low, a strong signal-of-interest is present. In this case, adaptive filter bias currents may be reduced raise the noise floor and degrade intermodulation to reduce power consumption because the strong signal-of-interest can tolerate the higher noise and distortion. When the RSSI level is low and AGC gain is high, a weak signal is present a low noise mode may be effected by increasing bias current to filters used to lower the noise floor, but intermodulation effects may still be tolerated so those filters may be cut back. Other cases are supported. RSSI and AGC gain level thresholds may be dynamically altered based on relative RSSI and AGC levels.
摘要:
To calibrate a bandpass filter, a received signal strength corresponding to a received communication channel is determined. A variable element of the bandpass filter is adjusted based on the received signal strength of the received communication channel to calibrate the bandpass filter.
摘要:
A receiver is set forth that includes a tuner circuit and a converter circuit. The tuner circuit provides an analog signal corresponding to a modulated signal that is received on a selected channel. The converter circuit includes a sample clock that is used to convert the analog signal to a digital signal at a conversion rate corresponding to the frequency of the sample clock. The sample clock is selectable between at least two different clock frequencies.
摘要:
Apparatus 20,30,40,50 for receiving and processing a wanted Radio Frequency signal comprises a radio frequency to intermediate frequency down-conversion stage 20 for receiving the wanted radio frequency signal and out-putting a complex intermediate frequency signal; an analogue to digital converter 30 for converting the complex intermediate frequency signal to a digital complex intermediate signal; an intermediate frequency to base-band down-conversion stage 40 for receiving the digital complex intermediate frequency signal and out-putting a digital complex base-band signal; and a complex notch filter 50 for receiving the digital complex base-band signal and out-putting a notch filtered digital complex base-band signal wherein the complex notch filter 50 substantially filters out a small portion of the base-band signal centred about a first, non-zero, frequency while substantially passing a corresponding portion of the base-band signal centred about a second frequency having the same magnitude but opposite sign to the first frequency.