摘要:
Provided are a wireless communications node (WCN) and a method therefor achieving mitigation of multipath interference via optimized estimation of coordinate location of the WCN relative to wireless communications with a plurality of reference points (RPs). To do so, the WCN effects a constrained gradient descent with respect to phase ranging measurements to one or more of the plurality to minimize a cost of error associated with the obtaining of such measurements.
摘要:
A method for determining a distance between a first and a second radio signal transceiver comprises receiving (2) a first and second sets of measurement results, wherein the first set is acquired by the first transceiver and transmitted by the second transceiver, the second set is acquired by the second transceiver and transmitted by first transceiver, the first set comprises, for each of a plurality of frequencies, a measurement pair of a phase value and a signal strength value and the second set of measurement results comprises, for each of said plurality of frequencies, a phase value or optionally a measurement pair of a phase value and a signal strength value; calculating (4), for each frequency a preliminary estimate of a value proportional to a one-way frequency domain channel response; calculating (5), for a frequency, a predicted estimate of a representation of said value proportional to said one-way frequency domain channel response, calculating a first (6a) and second (6b) metric distance between said predicted estimate for said frequency and a representation of said preliminary estimate for said frequency or a phase reversal of said representation of said preliminary estimate for said frequency (respectively); determining (8), a final estimate of said value based on a comparison of first metric distance and second metric distance, and determining (10) the distance between the first and the second transceiver based on a plurality of such final estimates.
摘要:
Die Erfindung betrifft ein Radar-Verfahren zum Signalaustausch zwischen mindestens zwei nicht-kohärenten Sende-Empfangseinheiten, die jeweils zunächst nicht- synchrone, insbesondere ansteuerbare, Taktquellen aufweisen, das folgende Schritte aufweist: eine Synchronisation, bei der Taktoffsets und/oder Taktraten der Taktquellen der mindestens zwei Sende-Empfangseinheiten angeglichen werden; ein Vollduplex-Messverfahren, bei dem ein erstes Sendesignal der ersten Sende- Empfangseinheit an die zweite Sende-Empfangseinheit und ein zweites Sendesignal der zweiten Sende-Empfangseinheit an die erste Sende-Empfangseinheit über einen Funkkanal, übertragen werden, wobei die Synchronisation vor dem Vollduplex- Messverfahren derart durchgeführt wird, dass ein Zeitversatz und/oder ein Frequenzversatz zwischen den Sendesignalen während einer Übertragungszeit des Vollduplex-Messverfahrens zumindest im Wesentlichen konstant bleibt/en.
摘要:
Markers and related systems and methods are provided for localizing lesions within a patient's body, e.g., within a breast. The marker includes one or more photosensitive diodes for transforming light pulses striking the marker into electrical energy, one or more antennas, and a switch coupled to the photodiodes and antennas such that the light pulses cause the switch to open and close and modulate radar signals reflected by the marker back to a source of the signals. The antenna(s) may include one or more wire elements extending from a housing, one or more antenna elements printed on a substrate, or one or more chip antennas. Optionally, the marker may include a processor coupled to the photodiodes for identifying signals in the light pulses or one or more coatings or filters to allow selective activation of the marker.
摘要:
System and method for signal modulation. In one embodiment, a circuit includes a channel for carrying an analog RF signal, a phase offset circuit on the channel, and configured to receive a phase code for modifying the analog RF signal to produce a modified RF signal, and a feedforward cancellation path coupled in parallel to the phase offset circuit for canceling a portion of the modified analog signal.
摘要:
La présente invention concerne un système de contrôle à distance ainsi qu'un procédé, notamment pour verrouiller et/ou pour déverrouiller automatiquement au moins un ouvrant d'un véhicule automobile et/ou pour démarrer un moteur d'un véhicule automobile, le système de contrôle à distance comprenant un module véhicule destiné à être installé à l'intérieur du véhicule, le système de contrôle à distance comprenant par ailleurs un module portatif destiné à être porté par un utilisateur du système de contrôle à distance, le système de contrôle à distance étant apte à déterminer la distance entre le module véhicule, d'une part, et le module portatif, d'autre part, par l'intermédiaire, d'une part, d'un premier signal radiofréquence émis par une antenne associée au module véhicule, et, d'autre part, d'un deuxième signal radiofréquence émis par une antenne associée au module portatif, le premier signal radiofréquence étant un signal obtenu par une modulation de phase ou par une modulation de fréquence, et le deuxième signal radiofréquence étant un signal obtenu en employant une boucle à verrouillage de phase dans le module portatif, la boucle à verrouillage de phase prenant le premier signal radiofréquence en tant que référence pour générer le deuxième signal radiofréquence.
摘要:
We describe a methods of locating an RFID tag. One method comprises: transmitting tag location signals from a plurality of different transmit antennas, wherein said antennas are spaced apart by more than a near field limit distance at a frequency of a said signal; receiving a corresponding plurality of receiving return signals from said tag; and processing said tag return signals to determine a range to said tag; wherein said transmitting comprises transmitting at a plurality of different frequencies; wherein said processing comprises determining a phase difference at said plurality of different frequencies to determine said range, and wherein said determining of said phase difference determines a phase difference between either i) two or more of said transmit signals resulting in a maxima in the returned signal RSSI or ii) a first transmit signal and its corresponding return signal; and wherein said determining of said range to said tag uses said return signals weighted responsive to a respective received signal strength of the return signal. Further data which may be used for averaging may be generated by using the above techniques along with changes in the polarisation state of the transmit and receive antennas and/or physical reconfiguration of the antennas (e.g. switch the transmit and receive elements).
摘要:
It is an object of the invention to provide a contactless reader/writer comprising a transmission section for transmitting a plurality of transmission signals using carrier waves of different frequencies, a reception section for receiving a plurality of reply signals which are a response to a plurality of transmission signals transmitted by the transmission section, a phase calculation section for calculating phase data of the reply signals on the basis of the reply signals, a distance calculation section for calculating a distance to an object having returned the reply signal, on the basis of the phase data from the phase calculation section and/or a speed calculation section for calculating a frequency component of baseband signals on the basis of the baseband signals acquired from the received signal, and thereby calculating a traveling speed of an object having returned the reply signal on the basis of the frequency component, and a control section for controlling a transmission direction of the transmission signals transmitted from the transmission section.