SIGNAL PROCESSING DEVICE FOR A COMMUNICATION SYSTEM USABLE IN PARTICULAR IN A BATTERY SYSTEM

Abstract

A signal processing device is usable in a communication system and includes a signal path, a signal detector, a signal synthesizer, a transmission unit, and a receive path including an analog-to-digital converter. The signal path transmits a transmission signal that was transmitted by the communication system and that contains a communication signal. The signal detector detects, and generates an activation signal in response to, an interference signal contained in the transmission signal and occurring due to narrowband interferences. The signal synthesizer generates an approximation signal for the interference signal upon the presence of the activation signal. The transmission unit receives the transmission signal transmitted by the signal path and the approximation signal, and outputs a difference signal between the transmission signal and the approximation signal. The analog-to-digital converter converts a signal generated based on the difference signal into a digital signal.

Claims

1-12. (canceled).

13. A signal processing device comprising: a signal path; a signal detector; a signal synthesizer; a transmitter; and an analog-to-digital converter; wherein: the signal path is configured to (a) receive a transmission signal transmitted by a communication system and containing a communication signal and (b) transmit the received transmission signal; the signal detector is configured to detect a presence of an interference signal contained in the transmission signal and occurring due to narrowband interferences; in response to the detection of the presence of the interference signal: the signal detector is configured to generate an activation signal; and the signal synthesizer is configured to generate an approximation signal that reproduces the interference signal within predefined tolerance limits; the transmitter is configured to (a) receive the transmission signal transmitted by the signal path and the approximation signal and (b) output a difference signal between the transmission signal and the approximation signal; and the analog-to-digital converter is configured to convert a signal that is generated based on the difference signal output by the transmitter into a digital signal.

14. The signal processing device of claim 13, wherein the signal detector is configured to generate the activation signal in response to an amplitude of the interference signal exceeding a predefined amplitude threshold value.

15. The signal processing device of claim 13, wherein the interference signal is a sinusoidal signal.

16. The signal processing device of claim 13, wherein the approximation signal is a periodic signal that corresponds to a triangle signal, a square-wave signal, or a sinusoidal signal.

17. The signal processing device of claim 13, wherein the signal synthesizer is an analog circuit including a comparator and an integrator.

18. The signal processing device of claim 13, wherein: the signal detector includes a determination unit; and the determination unit is configured to: determine a crest factor of the transmission signal; and detect the presence of the interference signal based on the determined crest factor.

19. The signal processing device of claim 18, wherein the signal synthesizer is an analog circuit including a comparator and an integrator.

20. The signal processing device of claim 19, wherein an input side of the comparator is connected to the determination unit and an output side of the comparator is connected to the integrator.

21. The signal processing device of claim 13, wherein the communication signal is a modulated signal.

22. The signal processing device of claim 21, wherein a crest factor of a carrier signal of the communication signal is different from a crest factor of the interference signal.

23. The signal processing device of claim 21, further comprising a demodulator, wherein the demodulator is configured to receive and demodulate the digital signal.

24. The signal processing device of claim 13, further comprising a bandpass filter, wherein: an input side of the bandpass filter is connected to the transmitter; an output side of the bandpass filter is connected to the analog-to-digital converter; and the bandpass filter is configured to let pass parts of its input signals which include frequencies which are in a frequency spectrum of the communication signal and to suppress parts of its input signals which include frequencies which are outside the frequency spectrum of the communication signal.

25. The signal processing device of claim 24, further comprising an automatic gain control, wherein: an input side of the automatic gain control is connected to the transmitter; an output side of the automatic gain control is connected to the analog-to-digital converter; and the automatic gain control is configured to amplify or attenuate its input signals and then output them in such a way that its output signals include amplitudes that are in a value range which is permissible for signal strengths of input signals of the analog-to-digital converter.

26. The signal processing device of claim 25, wherein the automatic gain control is connected between the bandpass filter and the analog-to-digital converter.

27. The signal processing device of claim 13, further comprising an automatic gain control, wherein: an input side of the automatic gain control is connected to the transmitter; an output side of the automatic gain control is connected to the analog-to-digital converter; and the automatic gain control is configured to amplify or attenuate its input signals and then output them in such a way that its output signals include amplitudes that are in a value range which is permissible for signal strengths of input signals of the analog-to-digital converter.

28. A communication system for a battery system comprising: a signal processing device; a battery that includes a plurality of battery modules, wherein each of the battery modules includes one or more battery cells; a plurality of communication lines; and a plurality of communication modules; wherein: the plurality of communication modules are configured to: monitor a functional state of the battery or of one of the battery modules; and communicate with one another via a communication signal contained in a transmission signal transmitted via the communication lines; the signal processing device includes a signal path, a signal detector, a signal synthesizer, a transmitter, and an analog-to-digital converter; the signal path is configured to (a) receive the transmission signal and (b) transmit the received transmission signal; the signal detector is configured to detect a presence of an interference signal contained in the transmission signal and occurring due to narrowband interferences; in response to the detection of the presence of the interference signal: the signal detector is configured to generate an activation signal; and the signal synthesizer is configured to generate an approximation signal that reproduces the interference signal within predefined tolerance limits; the transmitter is configured to (a) receive the transmission signal transmitted by the signal path and the approximation signal and (b) output a difference signal between the transmission signal and the approximation signal; and the analog-to-digital converter is configured to convert a signal that is generated based on the difference signal output by the transmitter into a digital signal.

29. The communication system of claim 29, wherein the communication lines at least partially correspond to power lines present in the battery system and are configured to transmit electric energy of the battery cells.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] FIG. 1 shows a signal processing device designed according to an example embodiment of the present invention for processing a transmission signal, which contains a communication signal and an interference signal.

[0045] FIG. 2 shows a curve of the transmission signal plotted in the time range according to an example embodiment of the present invention.

[0046] FIG. 3 shows a curve of the transmission signal plotted in the frequency range according to an example embodiment of the present invention.

[0047] FIG. 4 shows a curve of an approximation signal, which reproduces the interference signal within predefined tolerance limits, plotted in the time range, according to an example embodiment of the present invention.

[0048] FIG. 5 shows a curve of the approximation signal plotted in the frequency range according to an example embodiment of the present invention.

[0049] FIG. 6 shows a curve of a difference signal, which is equal to a difference between the transmission signal and the approximation signal, plotted in the time range, according to an example embodiment of the present invention.

[0050] FIG. 7 shows a curve of the difference signal plotted in the frequency range according to an example embodiment of the present invention.

DETAILED DESCRIPTION

[0051] FIG. 1 shows a signal processing device 1 for a communication system (not shown) usable in a battery system and designed as a battery management system. The signal processing device includes a signal path 10, which is designed to receive a transmission signal U transmitted by the communication system and transmit it further. Transmission signal U contains a communication signal and an interference signal occurring due to narrowband interferences and can be represented as a sum of the communication signal and the interference signal. The communication signal is a signal modulated using one or multiple carrier signal(s). The interference signal occurs in the form of a sinusoidal signal and has a crest factor of approximately 1.41. A crest factor of the interference signal is different from a crest factor of the communication signal.

[0052] Furthermore, signal processing device 1 includes a signal detector 30, which is designed to detect a presence of the interference signal and to generate an activation signal upon the presence of the interference signal. In particular, signal detector 30 is designed to generate the activation signal upon the presence of an amplitude of the interference signal that exceeds a predefined amplitude limiting value. Signal detector 30 includes a determination unit 31, which is designed to determine a crest factor of transmission signal U and to detect the presence of the interference signal based on the determined crest factor.

[0053] Furthermore, signal processing device 1 includes a signal synthesizer 40, which is designed to generate an approximation signal A, which reproduces the interference signal within predefined tolerance limits, upon the presence of the activation signal. Signal synthesizer 40 is designed in the form of an analog circuit including a comparator 41 and an integrator 42, comparator 41 being connected on the input side to determination unit 31 and on the output side to integrator 42. Comparator 41 is activated using the activation signal upon the presence of the interference signal. The analog circuit then generates approximation signal A in the form of a periodic signal, which corresponds to a triangle signal, a square-wave signal, or a sinusoidal signal.

[0054] Signal processing device 1 furthermore includes a transmission unit 50, which is designed to receive transmission signal U transmitted by signal path 10 and approximation signal A and to output a difference signal D, which is equal to a difference between transmission signal U and approximation signal A.

[0055] Signal processing device 1 furthermore includes a receive path for receiving difference signal D. The receive path includes a bandpass filter 60 connected downstream from transmission unit 50, an automatic gain control 70 connected downstream from bandpass filter 60, an analog-to-digital converter 80 connected downstream from automatic gain control 70, and a demodulator 90 connected downstream from analog-to-digital converter 80.

[0056] Bandpass filter 60 is designed to receive difference signal D and output it as filtered difference signal D1. Bandpass filter 60 is designed to let pass parts of difference signal D that include frequencies in a frequency spectrum of the communication signal and to suppress parts of difference signal D that include frequencies outside the frequency spectrum of the communication signal.

[0057] Automatic gain control 70 is designed to receive filtered difference signal D1, amplify or attenuate filtered difference signal D1, and output it as an amplified or attenuated difference signal D2. Filtered difference signal D1 is amplified or attenuated using automatic gain control 70 in such a way that an amplitude of amplified or attenuated difference signal D2 is in a value range that is permissible for signal strengths of input signals of analog-to-digital converter 80.

[0058] Analog-to-digital converter 80 is designed to receive amplified or attenuated difference signal D2 and convert it into a digital signal D3.

[0059] Demodulator 90 is designed to receive and demodulate digital signal D3.

[0060] FIG. 2 shows a curve UV1 of a signal strength of transmission signal U as a function of time measured in microseconds (s) (a microsecond being equal to 10.sup.6 seconds). Unitless values are indicated on an axis identified with UA in FIG. 2, which can be assumed from the signal strength of transmission signal U standardized to a predefined signal strength value. In the example shown in FIG. 2, the communication signal contained in transmission signal U is a signal modulated using an orthogonal frequency multiplexing method. This means that in the example shown in FIG. 2, the communication signal is modulated using multiple carrier frequencies 50. A curve of a symbol associated with this communication signal is made up of a sum of all four modulated carrier frequencies.

[0061] FIG. 3 shows a curve UV2 of a power level of transmission signal U shown in FIG. 2 as a function of frequency f measured in megahertz (MHz). In FIG. 3, values in decibel milliwatts (dBm), which can be assumed from the power level of transmission signal U, are indicated on an axis identified with UP. A decibel-milliwatt is a unit of a power level which describes the ratio of a power in comparison to a reference performance of one milliwatt, and one milliwatt is equal to 10.sup.3 W.

[0062] In the example shown in FIG. 3, the power level of transmission signal U at a frequency of approximately 10 MHz has a strongly inflated value due to a high amplitude of the interference signal. This value is approximately 9.2 dBm and is therefore more than 40 dB greater than a value which is assumed from a power level of the communication signal at the same frequency.

[0063] FIG. 4 shows a curve AV1 of a signal strength of approximation signal A as a function of time t measured in microseconds. In FIG. 4, unitless values, which can be assumed from the signal strength of approximation signal A, standardized to a predefined signal strength value, are indicated on an axis identified by AA. In the example shown in FIG. 4, approximation signal A is a periodic signal, which corresponds to a triangle signal. In the example shown in FIG. 4, approximation signal A reproduces the interference signal, which is contained in transmission signal U illustrated in FIG. 2, within predefined tolerance limits.

[0064] FIG. 5 shows a curve AV2 of a power level of approximation signal A shown in FIG. 4 as a function of frequency f measured in megahertz (MHz). In FIG. 5, values in decibel-milliwatts, which can be assumed from the power level of approximation signal A, are indicated on an axis identified by AP. It is apparent from FIG. 5 that the power level of approximation signal A assumes a maximum value of 9 dBm at a frequency of 10 MHz.

[0065] FIG. 6 shows a curve DV1 of a signal strength of difference signal D as a function of time t measured in microseconds. In FIG. 4, unitless values, which can be assumed from the signal strength of difference signal D standardized to a predefined signal strength value, are indicated on an axis identified with DA. In the example shown in FIG. 6, difference signal D is obtained by subtraction of approximation signal A shown in FIG. 4 from transmission signal U shown in FIG. 2.

[0066] FIG. 7 shows a curve DV2 of a power level of difference signal D shown in FIG. 6 as a function of frequency f measured in megahertz (MHz). In FIG. 7, values in decibel milliwatts, which can be assumed from the power level of difference signal D, are indicated on an axis identified by DP. It is apparent from FIG. 7 that at a frequency of 10 MHz, the power level of difference signal D has a value which is approximately 21.43 dBm and is therefore almost 30 dB less than the value which is assumed from the power level of transmission signal U shown in FIG. 3 at the same frequency. It is furthermore apparent from FIG. 7 that harmonics of approximation signal A are outside a frequency spectrum of the communication signal, in particular outside that of the symbol associated with the communication signal, and therefore can be filtered out easily using bandpass filter 60.

[0067] In addition to the written disclosure above, reference is additionally made to the illustration in FIGS. 1-7 for the further disclosure of the present invention.