摘要:
The present invention relates to a band rejection filter. The band rejection filter includes a first signal transmission channel called a direct channel and a second signal transmission channel called a secondary channel. The direct channel and the secondary channel being designed to introduce at a first rejection frequency a phase difference of 180° between the signal circulating via the direct channel and the signal circulating via the secondary channel. Additionally, the secondary channel includes a filtering element for which the cut-off frequency is different from the first rejection frequency in a way to create a second rejection frequency.
摘要:
The invention provides a dielectric resonator oscillator DR, especially for transmission devices whose oscillating frequency may take several values. The oscillator uses two interfering conductors 30 and 31 switched so that they may or may not form a metal plane close to the dielectric resonator DR in order to vary the frequency of the oscillator while using a single resonator. The interfering conductors 30 and 31 are located in the cavity CAV close to the resonator DR and the switching means may or may not establish an electrical contact between the said interfering conductors 30 and 31.
摘要:
The present invention relates to a terminal for the broadband transmission of video, audio or data signals in a domestic environment. It applies more specifically in the scope of terminals operating according to the standard IEEE 802.11n and employing simultaneously several frequency channels in a predetermined band of frequencies, for example the 5 GHz WiFi band. The terminal comprises M antennas, a MIMO device able to generate MIMO signals in said predetermined frequency band from baseband signals or conversely, said MEMO device being able to process N MIMO signals simultaneously, and a switching device to connect the MIMO device to the M antennas. According to the invention, the NINO device comprises two MIMO circuits, one operating in a first sub-band of the predetermined band and the other in a second sub-band of the predetermined band, the two sub bands being non-overlapping and the switching device is adapted to connect said two MIMO circuits to the antennas so that each of said M antennas is able to receive or transmit one of the MIMO signals of the first MIMO circuit and to receive or transmit one of the MIMO signals of the second MIMO circuit simultaneously. The switching device also comprises a filtering device associated with each antenna in order to isolate, in reception, the MIMO signal of the first sub-band of the MIMO signal from the second sub-band received or transmitted by said antenna.
摘要:
The invention concerns a system of antennas on the same support. Each antenna is connected to a first port for the emission/reception in a first frequency band, and to a second port for the emission/reception in a second frequency band. The invention consists in a specific dimensioning of the support, such that the difference of the perimetric lengths separating the median points is a function of the half wavelength λ/2 modulo k λ, k positive integer, where λ is the wavelength corresponding to a working frequency fr.
摘要:
The present invention relates to a high rejection stop band filter and a diplexer using such filters.The stop band filter comprises on a substrate with a ground plane, a transmission line extending between an input and an output and comprises several resonators formed of “stubs” in printed open circuit embedded into the transmission line, the resonators being positioned in parallel together and interconnected in series in the same direction or head to tail.The filters are particularly useful in mobile devices operating in two concurrent frequency bands.
摘要:
The method of improving the carrier-to-noise ratio for a receiver with diversity, and the associated device, consists, after extracting, by phase shifting, the noise component of the signals to be demodulated, in optimizing the cancellation of the useful component via a feedback loop acting on the phase shifter and in summing the noise component in phase and in phase opposition with these signals to improve the carrier-to-noise ratio.
摘要:
The invention relates to a method of compensating the Doppler effect for a mobile receiver. This method consists in producing a phase-locked loop based on the signal to be demodulated to correct the frequency control of the tuner element and thus the drift due to the Doppler effect. The invention also relates to a receiver implementing this method.
摘要:
The invention relates to a wideband phase shift device. A phase shift φ is introduced on the fixed frequency local oscillator. The principle of the invention is to realise a double translation of the input signals. The phase variation introduced at the level of the local oscillator has a positive value on one of the translated signals and a negative value on the other. The signals are recombined at the reception frequency with a phase difference of 2 φ so as to maximise the amplitude of the signal at the output of the summator.
摘要:
This invention relates to an antenna comprising at least one radiating device, furnished with a rejector filter associated with a frequency band of an interfering signal. In accordance with the invention, such an antenna is characterized in that this rejector filter is adaptive, so as to be active when the interfering signal is detected and its power is above a threshold, this adaptive filter being deactivated when the detected power of this interfering signal is below the threshold.
摘要:
The invention is a device and a method for cancelling interferences between signals with frequency proximity, inherent to the co-location of multi-standard terminals, in a communication system. The interfering signal is sampled either on the interfering signal or on the disturbed signal then phase shifted and attenuated according to the level of the disturbance and summed with the disturbed signal, so forming a neutralizing loop that can cancel the disturbance