Multi-channel reception systems, methods for calibrating a multi-channel reception system and methods for simulating the reception of a predetermined wave at a multi-channel reception system

Description

Technical field

[0001] The present disclosure relates to multi-channel receiving systems. In particular, exemplary embodiments relate to multi-channel receiving systems, methods for calibrating a multi-channel receiving system, and methods for simulating the reception of a predetermined wave at a multi-channel receiving system. background

[0002] A distributed multi-sensor receiving system samples a common wave field and therefore requires coherent sampling and signal processing in the individual N receiving channels. For the associated beamforming, it is important that the relative phase and amplitude response of the transfer functions of the individual receiving channels is known.

[0003] For simultaneous calibration, all receiving channels are excited with a known, unambiguous reference signal. The various coupling effects between the N receiving channels must be taken into account. Conventional calibration methods use either an external calibration antenna, which transmits a reference signal with known propagation characteristics to all receiving channels, or coupling a reference signal directly into the N receiving module inputs via a fixed distribution network. However, this approach does not allow for the distribution of a calibration signal with an arbitrary time course to the individual receiving channels, thus preventing the unambiguous assignment of the relevant input and output signals of the receiving channel to be calibrated while simultaneously identifying the received interference signals. Furthermore, these approaches cannot replicate the reception of an arbitrarily oriented plane wave with the receiving aperture.

[0004] Furthermore, document US 4,719,465 A relates to a monopulse radar system that has first and second emitters in symmetrical positions about the central axis to transmit radar pulses in a predefined cycle, thus generating first and second directional radiation patterns. A beamforming network synthesizes the first and second directional radiation patterns in phase and antiphase relationships to form a sum and difference pattern. A multichannel receiver generates from the sum and difference patterns an off-axis signal, which deviates from the central axis, as well as a sidelobe-suppressed signal, which is generated by suppressing a sidelobe reaction of the sum pattern. The first and second directional couplers are arranged on the transmission paths of the sum and difference patterns between the beamforming network and the multichannel receiver.The first and second calibration signals, with the same amplitude and phase, are fed into the transmission channels of the sum and difference patterns via the first and second directional couplers. The calibration signal is detected at the output of the multi-channel receiver, and the phase characteristics between the transmission channels of the sum and difference patterns are compensated according to the detection result.

[0005] Document US 3 229 289 A also concerns a microwave monopulse simulation device.

[0006] Document WO 2014 / 191795 A1 also relates to a receiver system and a receiver testing procedure. The receiver system includes a self-test circuit in which a local oscillator test signal is generated by an integrated frequency multiplier and mixed with an RF test signal in a down-converter. The RF test signal is generated by up-converting an externally generated low-frequency test signal with the local oscillator test signal. Baseband components can also be tested with test signals of a suitable frequency, which are separated from the local oscillator test signal by a programmable frequency divider.

[0007] Against this background, providing an improved multi-channel reception system is a task. Summary

[0008] The invention achieves this problem by means of multi-channel receiving systems and methods for calibrating a multi-channel receiving system according to the independent claims. Further aspects and embodiments of the invention are described in the dependent claims, the following description, and the figures.

[0009] A method for simulating the reception of a predetermined wave on a multi-channel receiving system is also disclosed.

[0010] A first embodiment relates to a first multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least one first receiver circuit and a second receiver circuit of the plurality of receiver circuits each comprise a signal input configured to receive a predetermined reference signal, and a modulation circuit configured to modulate the reference signal based on a respective control signal in order to generate a calibration signal for the respective receiver circuit. Furthermore, the multi-channel receiving system comprises a feed circuit configured to apply the predetermined reference signal to the respective signal input of at least the first receiver circuit and the second receiver circuit.The multi-channel receiving system further comprises a control circuit configured to generate the respective control signal for at least the first receiver circuit and the second receiver circuit such that the reference signal is individually phase-modulated by the respective modulation circuit for each receiver circuit. A second embodiment relates to a method for calibrating a multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least a first receiver circuit and a second receiver circuit of the plurality of receiver circuits each comprise a signal input configured to receive a predetermined reference signal and a modulation circuit configured to modulate the reference signal based on a control signal in order to generate a calibration signal for the respective receiver circuit.The method comprises applying the predetermined reference signal to the respective signal input of at least the first and second receiver circuits. Furthermore, the method comprises generating the respective control signal for at least the first and second receiver circuits such that the reference signal is individually phase-modulated by the respective modulation circuit for each receiver circuit.

[0011] A third embodiment relates to another multi-channel receiving system. This multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least one first receiver circuit and one second receiver circuit of the plurality of receiver circuits each comprise a signal input that can be coupled to a receiving element associated with the respective receiver circuit in order to receive a received signal for the respective receiving channel, and a signal generator configured to generate a calibration signal that is phase-modulated individually for the respective receiver circuit.Furthermore, at least the first receiver circuit and the second receiver circuit of the majority of receiver circuits each comprise a signal processing circuit configured to generate a digital output signal of the respective receiver circuit based on an input signal, and a distribution circuit configured to selectively apply the respective received signal or the calibration signal generated by the signal generator of the respective receiver circuit as an input signal to the signal processing circuit.

[0012] A fourth embodiment relates to a further method for calibrating a multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least a first receiver circuit and a second receiver circuit of the plurality of receiver circuits each comprise a signal input that can be coupled to a receiving element associated with the respective receiver circuit in order to receive a received signal for the respective receiving channel, and a signal processing circuit configured to generate a digital output signal of the respective receiver circuit based on an input signal. For at least the first receiver circuit and the second receiver circuit, the method comprises generating a calibration signal, which is phase-modulated individually for the respective receiver circuit, by a respective signal generator of the respective receiver circuit.Furthermore, the method for at least the first receiver circuit and the second receiver circuit includes selectively applying the calibration signal generated by the signal generator of the respective receiver circuit to the respective signal processing circuit by means of a respective distribution circuit of the respective receiver circuit.

[0013] The multi-channel receiving systems and methods according to the invention, as described in the first to fourth embodiments, enable individual phase evaluation for each receiving channel, thus allowing for unambiguous discrimination of the respective calibration signal from other coupled interference components. In a subsequent signal evaluation, the calibration signal can be extracted from the received total spectrum, thereby enabling an unambiguous determination of the transmission characteristics of each receiving channel. Accordingly, simultaneous calibration of the receiving channels is possible.

[0014] A fifth embodiment relates to a multi-channel receiving system for simulating the reception of a predetermined wave at the multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. Each plurality of receiver circuits comprises a signal input that can be coupled to a receiving element associated with the respective receiver circuit in order to receive a real received signal for the respective receiving channel, and a second signal input configured to receive a predetermined reference signal. Furthermore, each plurality of receiver circuits comprises a modulation circuit configured to modulate the reference signal based on a control signal in order to generate a synthetic received signal for the respective receiver circuit.The multi-channel receiving system comprises a feed circuit configured to apply the predetermined reference signal to the respective second signal input of at least a subset of the plurality of receiver circuits. Furthermore, the multi-channel receiving system comprises a control circuit configured to generate the respective control signal for at least the subset of the plurality of receiver circuits based on information indicating an expected received signal for the respective receiving channel upon actual reception of the predetermined wave by the receiving element assigned to the respective receiver circuit.

[0015] A sixth embodiment relates to a method for simulating the reception of a predetermined wave at a multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. Each of the plurality of receiver circuits comprises a signal input that can be coupled to a receiving element associated with the respective receiver circuit in order to receive a real received signal for the respective receiving channel, a second signal input configured to receive a predetermined reference signal, and a modulation circuit configured to modulate the reference signal based on a control signal in order to generate a synthetic received signal for the respective receiver circuit.The method comprises applying the predetermined reference signal to the respective second signal input of at least a subset of the plurality of receiver circuits and generating the respective control signal for at least the subset of the plurality of receiver circuits based on information that indicates an expected received signal for the respective receiving channel when the predetermined wave is actually received by the receiving element assigned to the respective receiver circuit.

[0016] A seventh embodiment relates to a further multi-channel receiving system for simulating the reception of a predetermined wave at the multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least a subset of the plurality of receiver circuits each comprises a first signal input that can be coupled to a receiving element assigned to the respective receiver circuit in order to receive a real received signal for the respective receiving channel, and a signal generator configured to generate a synthetic received signal for the respective receiver circuit based on information indicating an expected received signal for the respective receiving channel upon actual reception of the predetermined wave by the receiving element assigned to the respective receiver circuit.Furthermore, at least the subset of the majority of receiver circuits each comprises a signal processing circuit configured to generate a digital output signal of the respective receiver circuit based on an input signal, and a distribution circuit configured to selectively apply the synthetic received signal generated by the signal generator of the respective receiver circuit as an input signal to the signal processing circuit of the respective receiver circuit.

[0017] An eighth embodiment relates to a further method for simulating the reception of a predetermined wave at a multi-channel receiving system. The multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. Each of the plurality of receiver circuits comprises a first signal input, which can be coupled to a receiving element assigned to the respective receiver circuit in order to receive a real received signal for the respective receiving channel, and a signal processing circuit configured to generate a digital output signal of the respective receiver circuit based on an input signal.For at least a subset of the plurality of receiver circuits, the method comprises generating a synthetic receive signal for the respective receiver circuit by a respective signal generator of the respective receiver circuit, based on information indicating an expected receive signal for the respective receive channel upon actual reception of the predetermined wave by the receiving element assigned to the respective receiver circuit. Furthermore, for at least the subset of the plurality of receiver circuits, the method comprises selectively applying the synthetic receive signal generated by the signal generator of the respective receiver circuit to the signal processing circuit of the respective receiver circuit.

[0018] The multi-channel reception systems and methods according to the fifth to eighth embodiments enable the reproduction or simulation of the reception of any wave (e.g., an arbitrarily oriented plane wave) on the multi-channel reception system and are not part of the invention. Character description

[0019] Some examples of devices and / or methods are explained in more detail below with reference to the accompanying figures. These show: Fig. 1 shows a first embodiment of a multi-channel reception system; Fig. 2 shows a first embodiment of a receiver circuit; Fig. 3 shows a second embodiment of a receiver circuit; Fig. 4 shows a flowchart of an exemplary embodiment of a method for calibrating a multi-channel receiving system; Fig. 5shows a flowchart of an embodiment of a method for simulating the reception of a predetermined wave on a multi-channel receiving system; Fig. 6 shows a second embodiment of a multi-channel reception system; Fig. 7 shows a third embodiment of a receiver circuit; Fig. 8 shows a flowchart of a further embodiment of a method for calibrating a multi-channel receiving system; and Fig. 9 Figure 1 shows a flowchart of another embodiment of a method for simulating the reception of a predetermined wave on a multi-channel receiving system. Description

[0020] Some examples are now described in more detail with reference to the accompanying figures. However, other possible examples are not limited to the features of these detailed embodiments. These may include modifications of the features, as well as equivalents and alternatives to the features. Furthermore, the terminology used herein to describe certain examples should not be considered restrictive for other possible examples.

[0021] Identical or similar reference symbols throughout the description of the figures refer to identical or similar elements or features, which may be implemented in an identical or modified form, while providing the same or a similar function. Furthermore, the thickness of lines, layers, and / or areas in the figures may be exaggerated for clarity.

[0022] When two elements A and B are combined using "or," this is to be understood as revealing all possible combinations, i.e., only A, only B, and A and B, unless explicitly defined otherwise in a specific case. As an alternative formulation for the same combinations, "at least one of A and B" or "A and / or B" can be used. This applies equivalently to combinations of more than two elements.

[0023] When a singular form, e.g., "ein, eine" and "der, die, das," is used, and the use of only a single element is neither explicitly nor implicitly defined as mandatory, further examples may also use multiple elements to implement the same function. If a function is subsequently described as being implemented using multiple elements, further examples may implement the same function using a single element or a single processing entity.It is further understood that the terms "include", "comprehensive", "exhibit" and / or "exhibit" when used describe the presence of the specified features, integers, steps, operations, processes, elements, components and / or a group thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, processes, elements, components and / or a group thereof.

[0024] Fig. 1Figure 1 shows a (e.g., radar) multi-channel receiving system 100 with N receiving channels, where N is a natural number and N ≥ 2. The multi-channel receiving system 100 comprises a plurality of N receiver circuits 110-1, 110-2, ..., 110-N for the plurality of receiving channels. Furthermore, the multi-channel receiving system 100 comprises a plurality of M distributed receiving elements 140-1, 140-2, ..., 140-M for the electromagnetic radiation to be received or measured. The number M of receiving elements can be equal to the number N of receiver circuits, such that each of the receiver circuits 110-1, 110-2, ..., 110-N is assigned to one of the plurality of receiving elements 140-1, 140-2, ..., 140-M. Alternatively, the number M of receiving elements can also differ from the number N of receiver circuits. For example, the number M of receiving elements can be twice the number N of receiver circuits, such that each of the receiver circuits is 110-1, 110-2, ..., 110-N two of the majority of receiving elements 140-1, 140-2, ..., 140-M are assigned. The majority of receiving elements 140-1, 140-2, ..., 140-M can be, for example, antennas.

[0025] During the (receiving or normal) operation of the multi-channel receiving system 100, the majority of receiving elements 140-1, 140-2, ..., 140-M receive at least partially one or more electromagnetic waves 180 (e.g. radar waves) and each output a received signal 141-1, 141-2, ..., 141-N for the respective receiving channel to the associated receiver circuit of the majority of receiver circuits 110-1, 110-2, ..., 110-N.

[0026] For the calibration of the N receiving channels or the plurality of N receiver circuits 110-1, 110-2, ..., 110-N, the multi-channel receiving system further comprises a power supply circuit 120 and a control circuit 130.

[0027] The calibration process is further described below with reference to Fig. 2 explained in more detail. Fig. 2Figure 2 shows a receiver circuit 200. At least the first receiver circuit 110-1 and the second receiver circuit 110-2 of the majority of receiver circuits 110-1, 110-2, ..., 110-N of the multi-channel receiver system 100 are configured like receiver circuit 200. Optionally, the other receiver circuits of the majority of receiver circuits 110-1, 110-2, ..., 110-N can also be configured like receiver circuit 200.

[0028] The receiver circuit 200 comprises a first signal input 211 configured to receive a predetermined reference signal 121. The reference signal 121 is provided by the power supply circuit 120 or applied to the signal input 211. With respect to the plurality of receiver circuits 110-1, 110-2, ..., 110-N of the multi-channel receiving system 100, the power supply circuit 120 is thus configured to apply the predetermined reference signal 121 (e.g., in parallel or simultaneously) to the respective first signal input 211 of at least the first receiver circuit 110-1 and the second receiver circuit 110-2. Optionally, the power supply circuit 120 can be configured to apply the predetermined reference signal 121 (e.g., in parallel or simultaneously) to the respective signal input 211 of each of the plurality of receiver circuits 110-1, 110-2, ..., 110-N. The power supply circuit 120 can be understood as a distribution network for the reference signal 121.The power supply circuit 120 can include multiple signal lines to apply the reference signal 121 to the respective first signal input of the receiver circuit. The reference signal 121 can, for example, be an oscillation signal such as a sine wave or a square wave. It is important to note that the same reference signal is distributed to each of the receiver circuits.

[0029] For example, the multi-channel receiving system 100 can include a signal generator 150, which is coupled to the power supply circuit 120 and configured to generate the reference signal 121. The signal generator 150 can, for example, include one or more oscillators and / or one or more phase-locked loops for generating the reference signal 121. Alternatively, the multi-channel receiving system 100 can include a reference signal input 160, which is coupled to the power supply circuit 120 and configured to receive the reference signal 121 from a signal generator (not shown) external to the multi-channel receiving system 100.

[0030] The receiver circuit 200 further comprises a second signal input 212, which can be coupled to, or is coupled to, the receiving element assigned to the respective receiver circuit from the majority of receiving elements 140-1, 140-2, ..., 140-M in order to receive the received signal 141-i for the respective receiving channel i (i = 1 ... N). The respective received signal 141-i is not used for calibration.

[0031] For the calibration of the receiver circuit 200, this includes a modulation circuit 213, which is coupled to the first signal input 211 and configured to modulate the reference signal 120 based on a respective control signal 131-i in order to generate a calibration signal 220-i for the receiver circuit 200. The respective control signal 131-i can, for example, be supplied at another input 211. Fig. 2The signal input of receiver circuit 200, not shown, is received by control circuit 130. Referring to the majority of receiver circuits 110-1, 110-2, ..., 110-N of the multi-channel receiver system 100, this means that the modulation circuit 213 of receiver circuit 110-1 modulates the reference signal 120 based on the control signal 131-1 to generate a first calibration signal for receiver circuit 110-1, while the modulation circuit 213 of receiver circuit 110-2 modulates the reference signal 120 based on the control signal 131-2 to generate a second calibration signal for receiver circuit 110-2, etc. In other words, the respective modulation circuit 213 of at least the first receiver circuit 110-1 and the second receiver circuit 110-2 is configured to generate the reference signal 120 based on the respective control signal 131-1, respectively.131-2 is modulated to generate a calibration signal for the respective receiver circuit 110-1 or 110-2. Optionally, the modulation circuits of the other receiver circuits of the majority of receiver circuits 110-1, 110-2, ..., 110-N can also be configured in this way.

[0032] The control circuit 130 is configured to generate the respective control signal 131-1 or 131-2 for at least the first receiver circuit 110-1 and the second receiver circuit 110-2 such that the reference signal 121 is individually phase-modulated by the respective modulation circuit 213 for the respective receiver circuit 110-1 or 110-2. In other words, the first calibration signal generated by the modulation circuit 213 of the first receiver circuit 110-1 and the second calibration signal generated by the modulation circuit 213 of the second receiver circuit for the second receiver circuit 110-2 are phase-modulated differently.For example, the first calibration signal for the first receiver circuit 110-1 generated by the modulation circuit 213 of the first receiver circuit 110-1 and the second calibration signal for the second receiver circuit 110-2 generated by the modulation circuit 213 of the second receiver circuit 110-2 can be phase-shifted replicates of the reference signal 121.For example, the modulation circuit 213 of the first receiver circuit 110-1 can be controlled via the control signal 131-1 to rotate the phase of the reference signal 121 in a first direction to obtain the first calibration signal for the first receiver circuit 110-1, and the modulation circuit 213 of the second receiver circuit 110-2 can be controlled via the control signal 131-2 to rotate the phase of the reference signal 121 in a second direction different from the first direction to obtain the second calibration signal for the second receiver circuit 110-2.

[0033] Optionally, the control circuit 130 can be configured to generate a control signal 131-i for each of the multiple receiver circuits 110-1, 110-2, ..., 110-N. In other words, the control circuit 130 can optionally be configured to generate the respective control signal 131-1, ..., 131-N for each of the multiple receiver circuits 110-1, 110-2, ..., 110-N such that the reference signal 121 is individually phase-modulated by the respective modulation circuit of each receiver circuit 110-1, 110-2, ..., 110-N. Thus, a calibration signal with individual phase modulation can be obtained for each receiving channel or for each of the multiple receiver circuits 110-1, 110-2, ..., 110-N.

[0034] The modulation circuit 213 can, for example, be configured as a controllable phase shifter or one or more controllable delay elements. However, it should be noted that the aforementioned configurations of the modulation circuit 213 are purely exemplary and the modulation circuit 213 can also be configured differently.

[0035] Optionally, the receiver circuit 200 can also include one or more components for further processing the respective calibration signal 220-i. For example, the receiver circuit 200 can include an attenuator 214 configured to adjust the signal level of the calibration signal 220-i generated by the modulation circuit 213 to a predetermined value or level. It should be noted, however, that the attenuator 214 is chosen purely as an example and the receiver circuit 200 can additionally or instead of the attenuator 214 also include one or more other components to modify or adjust a signal characteristic of the respective calibration signal 220-i.

[0036] The receiver circuit 200 further comprises a signal processing circuit 216, which is configured to generate a respective digital output signal 111-i of the receiver circuit 200 based on an input signal (e.g., analog). With regard to the majority of receiver circuits 110-1, 110-2, ..., 110-N of the multi-channel receiving system 100, this means that the respective signal processing circuit 216 of at least the first receiver circuit 110-1 and the second receiver circuit 110-2 is configured to generate the digital output signal 111-1 or 111-2 of the respective receiver circuit 110-1 or 110-2 based on a respective input signal. Optionally, the signal processing circuits 216 of the further receiver circuits of the majority of receiver circuits 110-1, 110-2, ..., 110-N can also be designed in such a way as to provide a respective digital output signal 111-1, 111-2, ..., 111-N.

[0037] The signal processing circuit 216 can comprise a variety of components for processing the input signal. For example, the signal processing circuit 216 can include one or more filters, one or more amplifiers, one or more limiters, one or more phase shifters, one or more attenuators, and / or one or more analog-to-digital converters. It should be noted, however, that the aforementioned components are purely examples and the signal processing circuit 216 can also contain fewer, more, or different components.

[0038] Furthermore, the receiver circuit 200 comprises a distribution circuit 215, which is configured to selectively apply the respective received signal 141-i or the calibration signal 220-i generated by the modulation circuit 213 of the receiver circuit 200 as an input signal to the signal processing circuit 216. For this purpose, the distribution circuit 215 can, for example, have one or more interconnected switches. Accordingly, for example, during the (receiving or normal) operation of the multi-channel receiver system 100, the respective received signal 141-i can be applied to the signal processing circuit 216, so that the respective digital output signal 111-i is based on the respective received signal 141-i.During calibration, the calibration signal 220-i generated by the modulation circuit 213 of the receiver circuit 200 can be applied to the signal processing circuit 216, so that the respective digital output signal 111-i is based on the respective calibration signal 220-i.

[0039] Referring again to Fig. 1The multi-channel receiver system 100 further comprises an evaluation circuit 150, which is configured to receive the respective calibration signal and the respective digital output signal 111-1 and 111-2, respectively, from at least the first receiver circuit 110-1 and the second receiver circuit 110-2. For example, the first receiver circuit 110-1 and the second receiver circuit 110-2 can each have one or more respective signal outputs that can be coupled to, or are coupled to, the evaluation circuit 150 and output the respective calibration signal and the respective digital output signal 111-1 and 111-2, respectively. The further receiver circuits of the plurality of receiver circuits 110-1, 110-2, ..., 110-N can be configured accordingly.

[0040] As previously described, the respective digital output signals 111-1 and 111-2 of the first receiver circuit 110-1 and the second receiver circuit 110-2 are based during calibration on the calibration signal generated by the modulation circuit 213 of the respective receiver circuit 110-1 and 110-2. Since the evaluation circuit 150 is provided with both the input signal of the respective signal processing circuit 216 of the first receiver circuit 110-1 and the second receiver circuit 110-2 in the form of the calibration signals, as well as the digital output signals 111-1 and 111-2 of the respective signal processing circuit 216 of the first receiver circuit 110-1 and the second receiver circuit 110-2, it can now determine the respective transmission behavior of the first receiver circuit 110-1 and the second receiver circuit 110-2.The transmission characteristics of the signal processing circuits 216 of the first receiver circuit 110-1 and the second receiver circuit 110-2 are determined by appropriate signal matching. This can be done according to known methods. The transmission characteristics describe the relationship between the input and output signals of the respective receiver circuit or the signal processing circuit of the respective receiver circuit.

[0041] With respect to the plurality of receiver circuits 110-1, 110-2, ..., 110-N of the multi-channel receiving system 100, the evaluation circuit 150 can be configured to obtain the respective calibration signal and the respective digital output signal 111-1, 111-2, ..., 110-N based on the respective calibration signal from each of the plurality of receiver circuits 110-1, 110-2, ..., 110-N. The evaluation circuit 150 can also be configured to determine the respective transmission characteristics of each of the plurality of receiver circuits 110-1, 110-2, ..., 110-N based on the respective calibration signal and the respective digital output signal 111-1, 111-2, ..., 111-N.

[0042] Due to the respective modulation circuit 213 of the receiver circuits and the individual control signal, a phase-modulated calibration signal can be provided for each receiving channel or receiver circuit. Accordingly, the evaluation circuit 150 can clearly distinguish the respective calibration signal from other coupled interference components. In particular, during signal evaluation by the evaluation circuit 150, the respective calibration signal can be extracted from the received total spectrum, thus enabling a clear determination of the transmission characteristics of the respective receiving channel. Simultaneous calibration of the receiving channels is therefore possible. For example, at least the first receiver circuit 110-1 and the second receiver circuit 110-2 can be calibrated in parallel (simultaneously).

[0043] The proposed architecture allows a reference signal with an arbitrary time course to be distributed across the individual receive channels by employing individual phase modulation in each channel. This enables the unambiguous assignment of the relevant input and output signals of each channel to be calibrated, while simultaneously identifying the received interference signals. As described above, a controllable phase shifter or delay element can be used at each receive channel input, which individually phase-modulates the reference signal provided for calibration. The respective calibration signal therefore contains an individual phase weighting at each receive channel, allowing for the unambiguous discrimination of the calibration signal from other coupled interference components.The proposed architecture therefore enables the unambiguous identification of the interference signals received by the individual radiators, as well as the interference signals directly coupled into the respective signal processing circuit (e.g., into an analog-to-digital converter of the signal processing circuit). Subsequent signal analysis allows the extraction of the reference signal from the received total spectrum and thus an unambiguous determination of the transmission characteristics of the receiving channels. This enables simultaneous calibration of all N receiving channels.

[0044] Fig. 3Figure 1 shows another receiver circuit 300, which is extended compared to the previously described receiver circuit 200. At least the first receiver circuit 110-1 and the second receiver circuit 110-2 of the majority of receiver circuits 110-1, 110-2, ..., 110-N of the multi-channel receiving system 100 can be configured like receiver circuit 300. Optionally, the other receiver circuits of the majority of receiver circuits 110-1, 110-2, ..., 110-N can also be configured like receiver circuit 300.

[0045] Like receiver circuit 200, receiver circuit 300 also includes a first signal input 311 for the reference signal 121 and a second signal input for the received signal 141-i of the respective receiving channel. Additionally, receiver circuit 200 includes a third signal input 313, which can be coupled to, or is coupled to, another receiving element assigned to receiver circuit 300 in order to receive a further received signal 142-i for the respective receiving channel. Receiver circuit 300 can be used, for example, if the received signal 141-i and the further received signal 142-i have different polarizations (e.g., horizontal and vertical).

[0046] The signal processing circuit 319 of the receiver circuit 300 is adapted accordingly and has a first signal processing path 319-1 for the received signal 141-i and a second signal processing path 319-2 for the further received signal 142-i. The respective digital output signal 111-i of the receiver circuit 300 is output at a signal output 316 of the receiver circuit 300. In (receiving or normal) operation of the multi-channel receiving system 100, the respective digital output signal 111-i is based on the respective received signal 141-i and the respective further received signal 142-i of the respective receiving channel.

[0047] In Fig. 3Furthermore, an exemplary configuration of the signal processing paths 319-1 and 319-2 with filters, amplifiers, attenuators, phase shifters, limiters, etc., is shown. It should be noted, however, that the configuration of the signal processing paths 319-1 and 319-2 is purely exemplary and the signal processing circuit 319 may also have fewer, more, or different components.

[0048] Analogous to the receiver circuit 200, the receiver circuit 300 also has a modulation circuit 317 in order to generate the respective individual calibration signal for the respective receiving channel by appropriate modulation of the reference signal 121.

[0049] In Fig. 3 Furthermore, the distribution circuit 314 for distributing the calibration signal is also shown. In the Fig. 3In the example shown, the distribution circuit 314 is implemented using three switches. Due to the high isolation of the switches, a high attenuation between the signal processing paths 319-1 and 319-2 can be achieved. However, this configuration is purely exemplary. The functionality of the distribution circuit 314 can also be achieved by any other suitable configuration.

[0050] The distribution circuit 314 is configured to selectively apply the respective received signal 141-1 or the calibration signal generated by the modulation circuit 317 of the receiver circuit 300 as an input signal to the first signal processing path 319-1. Furthermore, the distribution circuit 314 is configured to selectively apply the respective additional received signal 142-1 or the calibration signal generated by the modulation circuit 317 of the receiver circuit 317 as an input signal to the second signal processing path 319-2. For example, the respective received signals 141-1 and 141-2 can be applied to the signal processing paths 319-1 and 319-2 during operation of the multi-channel receiving system 100.Accordingly, the respective calibration signal can be applied to the signal processing paths 319-1 and 319-2 during the calibration of the multi-channel receiving system 100, so that the respective digital output signal 111-i is based on the respective, individual calibration signal for the respective receiving path.

[0051] Similarly, the distribution circuit 314 can output the respective calibration signal to a further signal output 315 of the receiver circuit 300. For example, the further signal output 315 can be coupled to, or already coupled to, the evaluation circuit 150, so that the evaluation circuit 150 can receive the respective calibration signal for determining the transmission characteristics of the receiver circuit.

[0052] The distribution circuit 314 can also apply the respective calibration signal to a terminating resistor of, for example, 50 Ω. This can be done, for example, during the operation of the multi-channel receiving system 100, in order to further attenuate the calibration signal and thus increase the isolation between the signal processing paths 319-1 and 319-2.

[0053] The phase shifters present in signal processing paths 319-1 and 319-2 allow the phase of the calibration signal to be further changed or adjusted in the respective signal processing path 319-1 or 319-2, in order to make the calibration signal, for example, more easily distinguishable from calibration signals of neighboring receiver circuits.

[0054] To summarize the aforementioned aspects regarding the calibration of the multi-channel reception system 100, it is necessary to... Fig. 4Furthermore, a flowchart of procedure 400 for calibrating a multi-channel receiving system is shown. Analogous to the above description, the multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least one first receiver circuit and one second receiver circuit of the plurality of receiver circuits each comprise a signal input and a modulation circuit. As described above, the signal input is configured to receive a predetermined reference signal. The modulation circuit is configured to modulate the reference signal based on a control signal, as described above, in order to generate a calibration signal for the respective receiver circuit.

[0055] Method 400 comprises applying (e.g., in parallel or simultaneously) the predetermined reference signal 402 to the respective signal input of at least the first receiver circuit and the second receiver circuit. Furthermore, method 400 comprises generating the respective control signal 404 for at least the first receiver circuit and the second receiver circuit such that the reference signal is phase-modulated individually by the respective modulation circuit for the respective receiver circuit.

[0056] According to method 400, a calibration signal, individually modulated with respect to its phase, can be provided for each receiving channel or receiver circuit. Subsequent signal analysis allows the respective calibration signal to be extracted from the received total spectrum, thus enabling a clear determination of the transmission characteristics of the respective receiving channel. Accordingly, simultaneous calibration of the receiving channels is possible.

[0057] Further details and aspects of Procedure 400 are discussed above in connection with the Figures 1 to 3 described in more detail. Procedure 400 may therefore additionally include one or more of the aspects described above.

[0058] The multi-channel receiver system 100 described above can also be used, according to another aspect, to simulate the reception of a predetermined wave. This will be explained below with reference to Fig. 5 described in more detail. Fig. 5 shows a flowchart of a procedure 500 for simulating the reception of a predetermined wave on a multi-channel receiving system as described above in connection with the Figures 1 to 3 was described.

[0059] As mentioned above in connection with Fig. 1 and Fig. 2 As described in more detail, the signal input 212 of each of the majority of receiver circuits 110-1, 110-2, ..., 110-N can be coupled or connected to a receiving element 140-1, 140-2 ..., 140-M assigned to the respective receiver circuit in order to receive a real received signal 114-1, 141-2, ..., 141-N for the respective receiving channel from the respective assigned receiving element 140-1, 140-2 ..., 140-M.

[0060] Furthermore, the control circuit 130 and the respective modulation circuit 213 or 317 of the majority of receiver circuits 110-1, 110-2, ..., 110-N can be used to simulate the reception of the predetermined wave. For this purpose, the respective modulation circuit 213 or 317 can be controlled via the control circuit 130 to modulate the reference signal 121 accordingly.

[0061] Method 500 therefore comprises applying (e.g., in parallel or simultaneously) the predetermined reference signal 121 to the respective signal input 211 of at least a subset of the plurality of receiver circuits 110-1, 110-2, ..., 110-N. Optionally, the predetermined reference signal 121 can be applied to the respective signal input of each of the plurality of receiver circuits 110-1, 110-2, ..., 110-N.

[0062] Furthermore, the method 500 comprises generating 504 the respective control signal 131-1, 131-2, ..., 131-N for at least the subset of the plurality of receiver circuits 110-1, 110-2, ..., 110-N based on information indicating, for the respective receiving channel, an expected received signal upon actual reception of the predetermined wave by the receiving element assigned to the respective receiver circuit. For example, the control circuit 130 generates the control signal 131-1 for the first receiver circuit 110-1 based on information indicating, for this receiving channel, the expected received signal upon actual reception of the predetermined wave by the receiving element 140-1 assigned to the receiver circuit 110-1.Accordingly, the control circuit 130 generates the control signal 131-2 for the second receiver circuit 110-2 based on information indicating the expected received signal for this receiving channel when the predetermined wave is actually received by the receiving element 140-2 assigned to the receiver circuit 110-2. Similarly, for each desired receiving channel, a synthetic received signal can be generated by the respective modulation circuit instead of the calibration signal, in order to simulate the reception of the predetermined wave at the multi-channel receiving system 100. The respective synthetic received signal indicates the respective expected received signal when the predetermined wave is actually received by the receiving element assigned to the respective receiver circuit.

[0063] Another advantage of the proposed internal reference signal distribution with, for example, a phase shifter or delay element in each receiving channel is the possibility of simulating the reception of, for example, an arbitrarily oriented plane wave with the receiving aperture.

[0064] The following refers to the Figures 6 to 8 Another alternative design of the proposed architecture is described, in which the phase-modulated calibration signal is generated directly in each receiving channel individually.

[0065] A corresponding (e.g. radar) multi-channel receiving system 600 is in Fig. 6The multi-channel receiving system 600 comprises a plurality of N receiver circuits 610-1, 610-2, ..., 610-N for a plurality of N receiving channels. Furthermore, the multi-channel receiving system 600 comprises a plurality of M receiving elements 620-1, 620-2, ..., 620-M. The number M of receiving elements can be equal to the number N of receiver circuits, such that each of the receiver circuits 610-1, 610-2, ..., 610-N is assigned to one of the plurality of receiving elements 620-1, 620-2, ..., 620-M. Alternatively, the number M of receiving elements can also differ from the number N of receiver circuits. For example, the number M of receiving elements can be twice the number N of receiver circuits, so that each of the receiver circuits 610-1, 610-2, ..., 610-N is assigned two of the plurality of receiving elements 620-1, 620-2, ..., 620-M. The plurality of receiving elements 620-1, 620-2, ..., 620-M can, for example, be antennas.

[0066] During the (receiving or normal) operation of the multi-channel receiving system 100, the majority of receiving elements 620-1, 620-2, ..., 620-M receive one or more electromagnetic waves 640 (e.g. radar waves) and each output a received signal 621-1, 621-2, ..., 621-N for the respective receiving channel to the associated receiver circuit of the majority of receiver circuits 610-1, 610-2, ..., 610-N.

[0067] Fig. 7 Figure 700 shows a receiver circuit. At least the first receiver circuit 610-1 and the second receiver circuit 610-2 of the majority of receiver circuits 610-1, 610-2, ..., 610-N of the multi-channel receiver system 600 are configured like receiver circuit 700. Optionally, the other receiver circuits of the majority of receiver circuits 610-1, 610-2, ..., 610-N can also be configured like receiver circuit 700.

[0068] The receiver circuit 700 includes a signal input 711, which can be coupled to the receiving element of the majority of receiving elements 140-1, 140-2, ..., 140-M assigned to the respective receiver circuit in order to receive the received signal 621-i for the respective receiving channel i (i =1 ... N).

[0069] The receiver circuit 700 further comprises a signal processing circuit 714, which is configured to generate a respective digital output signal 611-i of the receiver circuit 700 based on an input signal (e.g., analog). With regard to the majority of receiver circuits 610-1, 610-2, ..., 610-N of the multi-channel receiving system 600, this means that the respective signal processing circuit 714 of at least the first receiver circuit 610-1 and the second receiver circuit 610-2 is configured to generate the respective digital output signal 611-1 or 611-2 of the respective receiver circuit 610-1 or 610-2 based on a respective input signal. Optionally, the signal processing circuits of the other receiver circuits of the majority of receiver circuits 610-1, 610-2, ..., 610-N can also be designed in such a way as to provide a respective digital output signal 611-1, 611-2, ..., 611-N.

[0070] The 714 signal processing circuit can include a variety of components for processing the input signal. For example, the 714 signal processing circuit can include one or more filters, one or more amplifiers, one or more limiters, one or more phase shifters, one or more attenuators, and / or one or more analog-to-digital converters. It should be noted, however, that the aforementioned components are purely examples, and the 714 signal processing circuit can also include fewer, more, or different components.

[0071] Furthermore, the receiver circuit 700 includes a distribution circuit 713, which is configured to selectively apply the respective received signal 621-i as an input signal to the signal processing circuit 714. For this purpose, the distribution circuit 713 can, for example, have one or more interconnected switches. Accordingly, during the (receiving or normal) operation of the multi-channel receiver system 600, the respective received signal 621-i can be applied to the signal processing circuit 714, so that the respective digital output signal 611-i is based on the respective received signal 621-i.

[0072] For the calibration of the receiver circuit 700, this includes a signal generator 712. The signal generator 712 is configured to generate a phase-modulated calibration signal 720-i individually for the respective receiver circuit. The signal generator 712 can, for example, include one or more oscillators and / or one or more phase-locked loops for generating the individually phase-modulated calibration signal 720-i. With respect to the majority of receiver circuits 610-1, 610-2, ..., 610-N of the multi-channel receiving system 600, this means that the signal generator 712 of the first receiver circuit 610-1 generates a first calibration signal that is phase-modulated individually for receiver circuit 610-1, while the signal generator 712 of the second receiver circuit 610-2 generates a second calibration signal that is phase-modulated individually for receiver circuit 610-2.In other words, the respective signal generator of at least the first receiver circuit 610-1 and the second receiver circuit 610-2 is each configured to generate a calibration signal that is individually phase-modulated for the respective receiver circuit 610-1 or 610-2. Optionally, the signal generators of the other receiver circuits of the majority of receiver circuits 610-1, 610-2, ..., 610-N can also be configured in this way.

[0073] The calibration signal for the first receiver circuit 610-1, generated by signal generator 712 of the first receiver circuit 610-1, and the calibration signal for the second receiver circuit, generated by signal generator 610-2, are phase-modulated differently. For example, the calibration signal for the first receiver circuit 610-1 generated by signal generator 712 of the first receiver circuit 610-1 and the calibration signal for the second receiver circuit 610-2 generated by signal generator 610-2 can be phase-shifted relative to each other (and otherwise identical).

[0074] Similar to the receiver circuit 200 described above, the receiver circuit 700 can also have one or more components for further processing of the respective calibration signal 220-i (e.g. an attenuator).

[0075] The distribution circuit 713 is further configured to selectively apply the respective individually phase-modulated calibration signal 720-i as an input signal to the signal processing circuit 714. During calibration, the calibration signal 720-i generated by the signal generator 712 of the receiver circuit 700 can be applied to the signal processing circuit 714, so that the respective digital output signal 111-i is based on the respective calibration signal 720-i.

[0076] Referring again to Fig. 6The multi-channel receiver system 600 further comprises an evaluation circuit 630, which is configured to receive the respective calibration signal and the respective digital output signal 611-1 and 611-2, respectively, from at least the first receiver circuit 610-1 and the second receiver circuit 610-2. For example, the first receiver circuit 610-1 and the second receiver circuit 610-2 can each have one or more respective signal outputs that can be coupled to, or are coupled to, the evaluation circuit 630 and output the respective calibration signal and the respective digital output signal 611-1 and 611-2, respectively. The further receiver circuits of the plurality of receiver circuits 610-1, 610-2, ..., 610-N can be configured accordingly.

[0077] As previously described, the respective digital output signals 611-1 and 611-2 of the first receiver circuit 610-1 and the second receiver circuit 610-2 are based during calibration on the individual calibration signal generated by the signal generator 712 of the respective receiver circuit 610-1 and 610-2. Since the evaluation circuit 630 receives both the input signal of the respective signal processing circuit 714 of the first receiver circuit 610-1 and the second receiver circuit 610-2 in the form of the calibration signals, as well as the respective digital output signals 611-1 and 611-2 of the respective signal processing circuit 714 of the first receiver circuit 610-1 and the second receiver circuit 610-2, it can in turn determine the respective transmission behavior of the first receiver circuit 610-1 and the second receiver circuit 610-2.The transmission characteristics of the signal processing circuits of the first receiver circuit 610-1 and the second receiver circuit 610-2 are determined by appropriate signal matching. This can be done according to known methods.

[0078] With respect to the plurality of receiver circuits 610-1, 610-2, ..., 610-N of the multi-channel receiving system 600, the evaluation circuit 630 can be configured to obtain the respective calibration signal and the respective digital output signal 611-1, 611-2, ..., 611-N based on the respective calibration signal from each of the plurality of receiver circuits 610-1, 610-2, ..., 610-N. The evaluation circuit 630 can also be configured to determine the respective transmission characteristics of each of the plurality of receiver circuits 610-1, 610-2, ..., 610-N based on the respective calibration signal and the respective digital output signal 611-1, 611-2, ..., 611-N.

[0079] Due to the individual phase modulation of the calibration signal for each receiving channel or receiver circuit, the evaluation circuit 630 can clearly distinguish the respective calibration signal from other coupled interference components. In particular, during signal evaluation by the evaluation circuit 630, the respective calibration signal can be extracted from the received total spectrum, thus enabling a clear determination of the transmission characteristics of the respective receiving channel. Accordingly, simultaneous calibration of the receiving channels is possible. For example, at least the first receiver circuit 610-1 and the second receiver circuit 610-2 can be calibrated in parallel.

[0080] The receiver circuits 610-1, 610-2, ..., 610-N can be used in a similar way to how they are used in connection with Fig. 3As described, it includes additional signal inputs for further received signals from a receiving channel. Accordingly, the signal processing circuit can be adapted and, for example, have signal processing paths for the individual received signals of the respective receiving channel.

[0081] To summarize the aforementioned aspects regarding the calibration of the 600 multi-channel receiver system, it is necessary to... Fig. 8Furthermore, a flowchart of a procedure 800 for calibrating a multi-channel receiving system is shown. Analogous to the above, the multi-channel receiving system comprises a plurality of receiver circuits for a plurality of receiving channels. At least one first receiver circuit and one second receiver circuit of the plurality of receiver circuits each comprise a signal input that can be coupled to a receiving element assigned to the respective receiver circuit in order to receive a received signal for the respective receiving channel. Furthermore, at least the first receiver circuit and the second receiver circuit each comprise a signal processing circuit configured to generate a digital output signal of the respective receiver circuit based on an input signal.

[0082] For at least the first receiver circuit and the second receiver circuit, the method 800 comprises generating (e.g., in parallel or simultaneously) a calibration signal 802, which is phase-modulated individually for the respective receiver circuit, by a respective signal generator of the respective receiver circuit. Furthermore, the method 800 comprises selectively applying the calibration signal 804 generated by the signal generator of the respective receiver circuit to the respective signal processing circuit by a respective distribution circuit of the respective receiver circuit.

[0083] According to method 800, a calibration signal, individually modulated with respect to its phase, can be provided for each receiving channel or receiver circuit. Subsequent signal analysis allows the respective calibration signal to be extracted from the received total spectrum, thus enabling a clear determination of the transmission characteristics of each receiving channel. Simultaneous calibration of the receiving channels is therefore possible.

[0084] Further details and aspects of Procedure 800 are discussed above in connection with the Figs. 6 and 7 described in more detail. Procedure 800 can therefore additionally include one or more of the aspects described above.

[0085] The previously described multi-channel receiver system 600 can also be used, according to another aspect, to simulate the reception of a predetermined wave. This will be explained below with reference to Fig. 9 described in more detail. Fig. 9 shows a flowchart of a procedure 900 for simulating the reception of a predetermined wave on a multi-channel receiving system as described above in connection with the Figs. 6 and 7 was described.

[0086] As mentioned above in connection with Fig. 6 and Fig. 7 As described in more detail, the signal input 711 of each of the majority of receiver circuits 610-1, 610-2, ..., 610-N can be coupled or connected to a receiving element 620-1, 620-2 ..., 620-M assigned to the respective receiver circuit in order to receive a real received signal 621-1, 621-2, ..., 621-N for the respective receiving channel from the respective assigned receiving element 620-1, 620-2 ..., 620-M.

[0087] Furthermore, the respective signal generator 712 can be used with the majority of receiver circuits 610-1, 610-2, ..., 610-N to simulate the reception of the predetermined wave.

[0088] Method 900 comprises, for at least a subset of the plurality of receiver circuits 610-1, 610-2, ..., 610-N, the (e.g., parallel or simultaneous) generation 902 of a synthetic receive signal for the respective receiver circuit by the respective signal generator 712 of the respective receiver circuit, based on information indicating an expected receive signal for the respective receive channel upon actual reception of the predetermined wave by the receiving element assigned to the respective receiver circuit. Optionally, for each receiver circuit of the plurality of receiver circuits 610-1, 610-2, ..., 610-N, a synthetic receive signal for the respective receiver circuit can be generated by the respective signal generator of the respective receiver circuit.

[0089] For example, the signal generator 712 of the first receiver circuit 610-1 generates a first synthetic receive signal for the receiver circuit 610-1 based on information indicating the expected received signal for this receive channel when the predetermined wave is actually received by the receiving element 620-1 associated with the receiver circuit 610-1. Similarly, the signal generator 712 of the second receiver circuit 610-2 generates a second synthetic receive signal for the receiver circuit 610-2 based on information indicating the expected received signal for this receive channel when the predetermined wave is actually received by the receiving element 620-2 associated with the receiver circuit 610-2. Each synthetic receive signal represents the respective expected received signal when the predetermined wave is actually received by the receiving element associated with the respective receiver circuit.

[0090] Furthermore, the method 900 comprises selectively applying 904 the synthetic receive signal generated by the signal generator of the respective receiver circuit to the signal processing circuit of the respective receiver circuit. For example, the distribution circuit 713 of the first receiver circuit 610-1 applies the synthetic receive signal generated by the signal generator 712 of the receiver circuit 610-1 to the signal processing circuit 714 of the receiver circuit 610-1. Similarly, the distribution circuit 713 of the second receiver circuit 610-2 applies the synthetic receive signal generated by the signal generator 712 of the receiver circuit 610-2 to the signal processing circuit 714 of the receiver circuit 610-2.

[0091] Accordingly, for each desired receiving channel, a synthetic receiving signal can be generated by the respective signal generator instead of the calibration signal and applied to the respective signal processing circuit in order to simulate the reception of the predetermined wave at the multi-channel receiving system 600. This makes it possible to replicate the reception of, for example, an arbitrarily oriented plane wave with the receiving aperture.

[0092] The above examples thus enable both phase modulation-based internal receiver calibration and receiver system verification for multi-sensor receiver systems.

[0093] The proposed architecture can be used, for example, in phased-array radars and other coherent multi-sensor receiving systems. Accordingly, the multi-channel receiving system 100 and the multi-channel receiving system 600 can be a phased-array radar or another coherent multi-sensor receiving system.

[0094] The aspects and features described in connection with one of the previous examples can also be combined with one or more of the further examples to replace an identical or similar feature of that further example or to additionally introduce the feature into the further example.

[0095] It is further understood that the disclosure of several steps, processes, operations, or functions disclosed in the description or claims should not be interpreted as necessarily occurring in the described sequence, unless explicitly stated in a specific case or required for technical reasons. Therefore, the preceding description does not restrict the execution of multiple steps or functions to a specific sequence. Furthermore, in other examples, a single step, function, process, or operation may include and / or be broken down into multiple sub-steps, functions, processes, or operations.

[0096] If certain aspects described in the preceding sections relate to a device or system, these aspects should also be understood as a description of the corresponding procedure. For example, a block, device, or functional aspect of the device or system may correspond to a feature, such as a process step, of the corresponding procedure. Similarly, aspects described in relation to a procedure should also be understood as a description of a corresponding block, element, property, or functional feature of that device or system.

[0097] The following claims are hereby included in the detailed description, each claim being a separate example. It should also be noted that—although a dependent claim may refer to a specific combination with one or more other claims—other examples may include a combination of the dependent claim with the subject matter of any other dependent or independent claim. Such combinations are hereby explicitly proposed unless it is stated in a specific case that a particular combination is not intended. Furthermore, features of a claim are also to be included for each other independent claim, even if that claim is not directly defined as dependent on that other independent claim.

Claims

1. A multi-channel reception system (100) comprising: a plurality of receiver circuits (110-1, ..., 110-N) for a plurality of reception channels, wherein at least a first receiver circuit and a second receiver circuit of the plurality of receiver circuits (110-1, ..., 110-N) each comprise: a signal input (211, 311) configured to receive a predetermined reference signal (121); and a modulation circuit (213, 317) configured to modulate the reference signal (121) based on a respective control signal (131-i) to generate a calibration signal (220-i) for the respective receiver circuit; a feed circuit (120) configured to apply the predetermined reference signal (121) to the respective signal input (211, 311) of at least the first receiver circuit and the second receiver circuit; and a control circuit (130) configured to generate the respective control signal (131-i) for at least the first receiver circuit and the second receiver circuit such that the reference signal (121) is individually phase modulated by the respective modulation circuit (213, 317) for the respective receiver circuit.

2. The multi-channel reception system (100) according to claim 1, wherein the calibration signal for the first receiver circuit generated by the modulation circuit (213, 317) of the first receiver circuit and the calibration signal for the second receiver circuit generated by the modulation circuit (213, 317) of the second receiver circuit are differently phase modulated.

3. The multi-channel reception system (100) according to claim 1 or claim 2, wherein the calibration signal for the first receiver circuit generated by the modulation circuit (213, 317) of the first receiver circuit and the calibration signal for the second receiver circuit generated by the modulation circuit (213, 317) of the second receiver circuit are mutually phase-shifted replicas of the reference signal (121).

4. The multi-channel reception system (100) according to any one of claims 1 to 3, further comprising an evaluation circuit (150) configured to: obtain from at least the first receiver circuit and the second receiver circuit the respective calibration signal (220-i) and a respective digital output signal (111-i) based on the calibration signal (220-i); and determine a respective transmission behavior of at least the first receiver circuit and the second receiver circuit based on the respective calibration signal (220-i) and the respective digital output signal (111-i).

5. The multi-channel reception system (100) according to any one of claims 1 to 4, wherein at least the first receiver circuit and the second receiver circuit of the plurality of receiver circuits (110-1, ..., 110-N) each comprise: a second signal input (212) couplable to a reception element (140-1, ..., 140-M) associated with the respective receiver circuit to receive a reception signal (141-i) for the respective reception channel; a signal processing circuit (216, 319) configured to generate a digital output signal of the respective receiver circuit based on an input signal; and a distribution circuit configured to selectively apply the respective reception signal (141-i) or the calibration signal (220-i) generated by the modulation circuit (213, 317) of the respective receiver circuit as an input signal to the signal processing circuit (216, 319).

6. The multi-channel reception system (100) according to claim 5, wherein at least the first receiver circuit and the second receiver circuit of the plurality of receiver circuits (110-1, ..., 110-N) each further comprise a third signal input (313) couplable to a further reception element associated with the respective receiver circuit to receive a further reception signal (142-i) for the respective reception channel, wherein the reception signal (141-i) and the further reception signal (142-i) have different polarizations, wherein the signal processing circuit (319) comprises a first signal processing path (319-1) for the reception signal and a second signal processing path (319-2) for the further reception signal (142-i), and wherein the distribution circuit is configured to: selectively apply the respective reception signal (141-i) or the calibration signal (220-i) generated by the modulation circuit (213, 317) of the respective receiver circuit as an input signal to the first signal processing path (319-1); and / or selectively apply the respective further reception signal (142-i) or the calibration signal (220-i) generated by the modulation circuit (213, 317) of the respective receiver circuit as an input signal to the second signal processing path (319-2).

7. The multi-channel reception system (100) according to claim 5 or claim 6, further comprising an attenuator (214) configured to set a signal level of the calibration signal (220-i) generated by the modulation circuit (213, 317) of the respective receiver circuit to a predetermined value.

8. The multi-channel reception system (100) according to any one of claims 1 to 7, wherein the modulation circuit (213, 317) is a controllable phase shifter or a controllable delay element.

9. The multi-channel reception system (100) according to any one of claims 1 to 8, further comprising a signal generator coupled to the feed circuit (120) and configured to generate the reference signal (121).

10. The multi-channel reception system (100) according to any one of claims 1 to 8, further comprising a reference signal input coupled to the feed circuit (120) and configured to receive the reference signal (121) from an external signal generator.

11. The multi-channel reception system (100) according to any one of claims 1 to 10, wherein also the further receiver circuits of the plurality of receiver circuits (110-1, ..., 110-N) each comprise a signal input (211, 311) and a modulation circuit (213, 317) configured like the signal input (211, 311) and the modulation circuit (213, 317) of the first and the second receiver circuit, wherein the feed circuit (120) is configured to apply the predetermined reference signal (121) to the respective signal input (211, 311) of each of the plurality of receiver circuits (110-1, ..., 110-N), and wherein the control circuit (130) is configured to generate the respective control signal (131-i) for each of the plurality of receiver circuits (110-1, ..., 110-N) such that the reference signal (121) is individually phase modulated by the respective modulation circuit (213, 317) of the respective receiver circuit.

12. A method (400) for calibrating a multi-channel reception system comprising a plurality of receiver circuits for a plurality of reception channels, wherein at least a first receiver circuit and a second receiver circuit of the plurality of receiver circuits each comprise a signal input configured to receive a predetermined reference signal and a modulation circuit configured to modulate the reference signal based on a control signal to generate a calibration signal for the respective receiver circuit, the method comprising: applying (402) the predetermined reference signal to the respective signal input of at least the first receiver circuit and the second receiver circuit; and generating (404) the respective control signal for at least the first receiver circuit and the second receiver circuit such that the reference signal is individually phase modulated by the respective modulation circuit for the respective receiver circuit.

13. A multi-channel reception system (600) comprising a plurality of receiver circuits (610-1, ..., 610-N) for a plurality of reception channels, wherein at least a first receiver circuit and a second receiver circuit of the plurality of receiver circuits (610-1, ..., 610-N) each comprise: a signal input (711) couplable to a reception element associated with the respective receiver circuit to receive a reception signal (621-i) for the respective reception channel; a signal generator (712) configured to generate a calibration signal (720-i) individually phase modulated for the respective receiver circuit; a signal processing circuit (714) configured to generate a digital output signal (611-i) of the respective receiver circuit based on an input signal; and a distribution circuit (713) configured to selectively apply the respective reception signal (621-i) or the calibration signal (720-i) generated by the signal generator of the respective receiver circuit as an input signal to the signal processing circuit (714).

14. The multi-channel reception system (600) according to claim 13, wherein the calibration signal for the first receiver circuit generated by the signal generator (712) of the first receiver circuit and the calibration signal for the second receiver circuit generated by the signal generator (712) of the second receiver circuit are differently phase modulated.

15. The multi-channel reception system (600) according to claim 13 or claim 14, wherein the calibration signal for the first receiver circuit generated by the signal generator (712) of the first receiver circuit and the calibration signal for the second receiver circuit generated by the signal generator (712) of the second receiver circuit are mutually phase-shifted.