Abstract: Methods for locating electromagnetic pulse emission sources in an environment including reflectors is disclosed. In one aspect, the method includes receiving, by a detector, for each source to be located, at least one same emitted pulse, received directly from said source and received by reflection on one of the reflectors. The method also includes identifying direct subsets and reflected subsets, regrouping by pairs of direct subsets with reflected subsets, calculating, for each pair, differences in dates of arrival between the pulses of the reflected subset and the pulses of the direct subset of the pair, and determining the distance of each source from the detector from calculated differences in dates of arrival of the pulses of each pair.

Abstract: The invention relates to a method for determining features of an electromagnetic wave received by a reception system (22), the reception system (22) comprising at least two reception channels (13), each reception channel (13) comprising an antenna (21) and a reception chain (14), each reception chain (14) being capable of delivering a value representative of the power delivered by the corresponding antenna (21) after reception of the wave by the reception system (22), the features comprising at least the direction of arrival of the received wave, the method comprising a step of providing a measurement vector, the method further comprising the following steps: comparing the measurement vector to calibration vectors, and determining features of the received wave from the result of the comparison.

Abstract: A radar includes an antennal structure, with means for transmitting an impulse signal in a band centered on F1 according to a repetition period centered on a recurrence period Tr1 and pulse width T1, with means for receiving signals by the antenna in frequency band ?F, with a unit for processing the signals received on a set of N distance bins. The signals received are transmitted by another radar in a frequency band centered on F2 where F2?F1??F, according to a repetition period centered on a period Tr2 and pulse width T2. The signals transmitted by the two radars are asynchronous. The method comprises: slaving frequency F1 to frequency F2, by measuring the power received integrated over the N distance bins and over several recurrences, determination of period Tr2 and T2 and slaving the period centered on Tr1 to a period centered on Tr2 with Tr1=k*Tr2.

Abstract: A reception system including a receiver coupled to a processing means, the receiver comprising a number N of antennas, each being able to pick up signals representative of incident waves and to deliver a pulse dependent on said signal, N being an integer. Said receiver includes: N delay lines respectively coupled to each of said N antennas, each delay line being able to delay the signal delivered by the antenna with which it is associated by its own time delay, a coupling means able to sum the N signals delivered by the N delay lines, so as to deliver an output signal comprising a series of N time-shifted pulses. The processing means includes a measurement means able to measure the signal delivered by the coupling means and to deliver as output a signal formed by measurement samples, representative of the N pulses delivered by the N antennas.

Abstract: A device for detecting and locating moving objects that are equipped with at least one radar comprises a radar function comprising an antenna disposed on a revolving structure and a radar emissions detector function comprising an antennal part, and is characterized in that the antennal part of the radar emissions detector function is placed on said revolving structure.

Abstract: A device is provided for use of an antennal base formed of two antennas which pick up the emissions present and produce two radioelectric signals S1 and S2. These two signals are used to produce at least one intermediate-frequency signal Fl by demodulation of one of the two signals by the other (autotransposition). The demodulation is carried out by firstly transposing one of the signals, S1 for example, around a given frequency F1, the signal S2 being preserved around its initial central frequency F0. Thus, whatever the central frequency F0 of the emission picked up by the antennas, the demodulation produces a signal of central frequency F1, thereafter demodulated into a given intermediate frequency Fl by a local oscillator of constant frequency F2=F1+Fl. The device is applied to the production of a device for detecting emissions and for characterizing the emissions picked up.

Abstract: A reception system including a receiver of superheterodyne type coupled to a processing means, the receiver including N antennas. Said receiver includes: N translation means, each being able to frequency translate signals delivered by the antenna considered, from a frequency sub-band of the span of interest to a restricted frequency band, and to frequency multiplex the signals belonging to said frequency sub-band; N first intermediate frequency bandpass filters, of bandwidth equal to said restricted frequency band, respectively coupled at the output of each translation means, and able to filter the translated and multiplexed signals; a coupling means able to sum the N filtered signals so as to deliver the set of summed signals via N outputs.

Abstract: A radar includes an antennal structure, with means for transmitting an impulse signal in a band centered on F1 according to a repetition period centered on a recurrence period Tr1 and pulse width T1, with means for receiving signals by the antenna in frequency band ?F, with a unit for processing the signals received on a set of N distance bins. The signals received are transmitted by another radar in a frequency band centered on F2 where F2?F1??F, according to a repetition period centered on a period Tr2 and pulse width T2. The signals transmitted by the two radars are asynchronous. The method comprises: slaving frequency F1 to frequency F2, by measuring the power received integrated over the N distance bins and over several recurrences, determination of period Tr2 and T2 and slaving the period centered on Tr1 to a period centered on Tr2 with Tr1=k*Tr2.

Abstract: Use of an antennal base formed of two antennas which pick up the emissions present and produce two radioelectric signals S1 and S2. These two signals are used to produce at least one intermediate-frequency signal Fl by demodulation of one of the two signals by the other (autotransposition). The demodulation is carried out by firstly transposing one of the signals, S1 for example, around a given frequency F1, the signal S2 being preserved around its initial central frequency F0. Thus, whatever the central frequency F0 of the emission picked up by the antennas, the demodulation produces a signal of central frequency F1, thereafter demodulated into a given intermediate frequency Fl by means of a local oscillator of constant frequency F2=F1+Fl. The device is applied to the production of a device for detecting emissions and for characterizing the emissions picked up.

Abstract: A reception system including a receiver of superheterodyne type coupled to a processing means, the receiver including N antennas. Said receiver includes: N translation means, each being able to frequency translate signals delivered by the antenna considered, from a frequency sub-band of the span of interest to a restricted frequency band, and to frequency multiplex the signals belonging to said frequency sub-band; N first intermediate frequency bandpass filters, of bandwidth equal to said restricted frequency band, respectively coupled at the output of each translation means, and able to filter the translated and multiplexed signals; a coupling means able to sum the N filtered signals so as to deliver the set of summed signals via N outputs.

Abstract: A reception system including a receiver coupled to a processing means, the receiver comprising a number N of antennas, each being able to pick up signals representative of incident waves and to deliver a pulse dependent on said signal, N being an integer. Said receiver includes: N delay lines respectively coupled to each of said N antennas, each delay line being able to delay the signal delivered by the antenna with which it is associated by its own time delay, a coupling means able to sum the N signals delivered by the N delay lines, so as to deliver an output signal comprising a series of N time-shifted pulses. The processing means includes a measurement means able to measure the signal delivered by the coupling means and to deliver as output a signal formed by measurement samples, representative of the N pulses delivered by the N antennas.