摘要:
A method may include generating for transmission a repeating sequence of N constant-frequency pulses of width t seconds at interpulse intervals of T seconds, with each pulse in the sequence having a particular constant phase according to a quadratic phase sequence, which phase is applied to each pulse in a first sense of modulation. The method may further include modulating the phase of echo energy received from one or more objects reflecting the transmitted repeating sequence of N constant-frequency pulses with a second sense of modulation opposite to the first sense of modulation. The method may further include producing from the modulated received echo energy N unique and discrete frequency translations of the received echo energy as a function of range r of the reflecting objects, of magnitude equal to multiples of 1/NT Hz, which may preserve the spectrum of the received echo energy, forming in combination a composite signal frequency spectrum.
摘要:
An I/Q mixer and processing method for a radar system include an RF input and an LO input. Phase shifters apply a selectable phase shift to the LO signal to produce a first phase-shifted version of the LO signal and a second phase-shifted version of the LO signal, the first and second phase-shifted versions of the LO signal being in quadrature. A first set of switches is controllable to selectively apply the selectable phase shift to the LO signal. A first mixer unit receives the RF signal at a first input of the first mixer unit, and a second mixer unit receives the RF signal at a first input of the second mixer unit. A second set of switches is controllable to apply one of the first and second phase-shifted versions of the LO signal to one of a second input of the first mixer unit and a second input of the second mixer unit and to apply the other of the first and second phase-shifted versions of the LO signal to the other of the second input of the first mixer unit and the second input of the second mixer unit. A counter generates a count for sequencing through states of the first and second sets of switches.
摘要:
The invention relates to a radar sensor comprising an oscillator (18) for generating a transmission signal and a mixer (22) for generating an intermediate frequency signal (IF) by mixing one part of the transmission signal (LO) with a received signal, and comprising an offset-compensation unit (35) for generating an oscillating compensation signal which is fed to the mixer (22) in addition to said part of the transmission signal (LO). The invention further relates to a method for operating a radar sensor.
摘要:
The method for operating a UWB device having at least one transmitting antenna and/or at least one receiving antenna comprises the following steps: - triggering the transmitting antenna (12) or the receiving antenna (12') with a triggering pulse signal (13, 13') having a sequence of substantially sinusoidal pulses of alternating polarity and differing amplitudes and particularly having the waveform of a fifth-order Gaussian pulse signal, - wherein the transmitting antenna (12) can be alternately supplied with current pulses of differing polarity and differing magnitude by switching on and off first electronic switch units (16) that are coupled to the transmitting antenna (12) and have resistances associated with the amplitudes of the pulses to be generated, - wherein each first switch unit (16) has a specifiable, particularly equal, number of first switching transistors(18,19), each having substantially identical on-state resistance values (R), - wherein the resistance of a first switch unit is adjusted either by using only one of the first switching transistors (18,19) or by using a plurality of first switching transistors (18,19) connected in parallel, and - wherein the first switch units (16) are triggered sequentially according to a first specifiable temporal schema and each for a triggering time interval of a predetermined length.
摘要:
The present disclosure concerns a method of post-processing of the radar data that uses the information of the Doppler speed obtained by the coherent processing of the input data, in order to calculate the radial speeds of the detected objects, in particular close to waterbodies. The present disclosure further concerns a coherent radar provided with means suitable to implement the method of the present disclosure.
摘要:
The invention relates to a radar sensor for motor vehicles, comprising a transmitter (10) that has two oscillators (16, 18) and a 90° phase shifter (26) for generating a transmission signal (S), a first comparison signal (V1) and a second comparison signal (V2) that is 90° phase-shifted as compared to the first comparison signal, and further comprising a receiver (12) having an I-mixer (32) for mixing a received signal (E) with the first comparison signal (V1) and a Q-mixer (34) for mixing the received signal with the second comparison signal (V2), characterized in that the transmitter (10) comprises a first transmit mixer (20), the inputs of which are directly connected to the two oscillators (16, 18), and a second transmit mixer (28), the one input of which is directly connected to a first (16) of the two oscillators and the other input of which is connected by means of the phase shifter (26) to the other oscillator (18).
摘要:
A method and apparatus of determining a wave height directional spectrum of an ocean wave field using the intermediate-frequency (IF) signal from marine radars with a rotating antenna, using either a fully coherent or a standard non-coherent transmitter/receiver modified for coherent-on-receive use. The method may include receiving the IF radar ocean surface echo signal for a series of transmit pulses, at a sequence of azimuthal antenna positions, and a number of antenna rotations covering several minutes, then generating a matrix of complex IF signal samples from these, deriving phases for each sample, generating the difference in phase for consecutive azimuths, then Doppler shifts, and finally radial velocities. These are interpolated to a Cartesian-transformed representation cube of samples, a subset of which is Fourier transformed in three dimensions, filtered, and the resulting power spectrum generated is used to derive ocean wave height directional spectra, frequency spectra, and root-mean-squared wave height.
摘要:
Die Erfindung betrifft ein Verfahren zur Auswertung von Signalen (ULS) einer Sensoreinheit mit mindestens einem Ultraschallsensor, wobei Ultraschallsignale in einen zu überwachenden Bereich ausgesendet und in Reaktion auf die ausgesendeten Ultraschallsignale Echosignale (ULS) empfangen und zur Erfassung von Objekten und/oder Objektbewegungen in dem zu überwachenden Bereich ausgewertet werden, wobei die empfangenen Echosignale (ULS) zur Auswertung einer Quadraturphasendetektion unterworfen werden, sowie eine Vorrichtung zur Umfelderfassung in einem Fahrzeug und ein Datenverarbeitungsprogramm und ein Computerprogrammprodukt zur Durchführung des Verfahrens. Um eine weitergehende Signalauswertung durch eine Quadraturphasendetektion zu vereinfachen und eine einfache Erzeugung von erforderlichen Referenzsignalen für die Quadraturphasendetektion zu ermöglichen, werden zur Quadraturphasendetektion erforderliche Referenzsignale (S1, S2, S3, S4) unter Verwendung von digitalen Logikverknüpfungen (12, 14, 16, 18) aus einem digitalen Basissignal (S0) erzeugt, wobei vier jeweils um 90° phasenverschobene Referenzsignale (S1, S2, S3, S4) erzeugt und jeweils einzeln mit den empfangenen Echosignalen (ULS) gemischt werden.
摘要:
Beschrieben wird ein Verfahren und eine Vorrichtung zum Bereitstellen eines Reflexionssignals, wobei ein erstes Referenzsignal (221) u.a. durch Mischen der zwei Ausgangssignale von zwei Frequenzgeneratoren (PLL1, PLL2) erzeugt wird und wobei das erste Referenzsignal (221) zur Demodulation (M2) eines Empfangssignals (RX) und zur Generierung des Abtasttaktes oder zur Erzeugung eines zweiten Referenzsignals (405) zur weiteren Demodulation (M4) des Empfangssignals dient.