RU98108294A - METHOD (OPTIONS) AND DEVICE (OPTIONS) FOR REDUCING RADIO INTERFERENCE ON THE MAIN CHANNEL - Google Patents

Claims (35)

1. A method of reducing radio interference on the main channel in the presence of a useful signal in a given frequency band in the received signal of the communication system, including the following operations: sampling the received signal to obtain samples of the signal x (k), each of which can be represented by a complex number; restriction of each sample in accordance with the function x (k) / | x (k) | to get a limited sample of the received signal.  2. The method in accordance with paragraph 1, which also includes filtering the limited samples of the received signal to remove components that are not in the specified frequency band.  3. The method in accordance with claim 2, which reduces radio interference on the main channel as a result of the following operations: digital processing of the filtered limited signal samples to obtain processed samples having components outside the specified frequency band; filtering the processed samples to remove components outside the specified frequency band.  4. The method in accordance with claim 2, further comprising the following operations: forming the first product of each filtered limited sample of the signal multiplied by its conjugate function; filtering the first product to remove the DC component from the frequency band of the modulating signals; generating a second product of each filtered limited sample of the signal multiplied by the filtered first product; generating a difference between each filtered limited sample of the signal and the second product; difference filtering to remove components outside in the specified frequency band.  5. The method in accordance with any one of claims 1 to 4, further comprising the step of converting the frequency of the received signal in the frequency band of the modulating signals before performing the sampling operation.  6. A method of reducing radio interference along the main channel in the samples of a complex signal x (k) of a frequency-modulated signal in a given frequency band of modulating signals, including the following operations: limiting each sample of a complex signal to form a limited sample equal to x (k) / | x (k ) | and filtering the limited signal samples in the low-pass filter to remove components outside a predetermined frequency band.  7. The method according to claim 6, further comprising the step of non-linearly filtering the filtered limited signal samples to further attenuate the radio interference along the main channel.  8. The method in accordance with claim 6, further comprising the steps of multiplying each filtered limited signal sample by its conjugate function, removing the DC component from the product, multiplying the result by the filtered limited signal sample, and filtering the low-pass filter for the difference between the final product and the limited sample signal to remove components outside the specified frequency band.  9. The method in accordance with any one of claims 1 to 8, further comprising the steps of: filtering the signal samples to generate from each signal sample a plurality of filtered samples representing the components of the signal samples in various narrow frequency ranges within a given frequency band; identification of one of the many filtered samples having maximum instantaneous energy; selecting at least one identified sample from the set of filtered samples as a signal sample having reduced interference on the main channel.  10. The method according to claim 9, wherein the filtering operation for generating a plurality of filtered samples follows the operation of restricting each sample.  11. A method of reducing radio interference on the main channel in the presence of a useful signal in a given frequency band in the received signal of the communication system, including the following operations: sampling the received signal to obtain samples of the signal, each of which can be represented by a complex number; filtering the signal samples to form from each signal sample a plurality of filtered samples representing the components of the signal sample in various narrow ranges within a given frequency band; identification of one of the many filtered samples having a maximum of instantaneous energy; selecting at least one identified sample from the set of filtered samples as a signal having reduced interference on the main channel.  12. The method in accordance with any one of claims 9 to 11, wherein there are at least three different narrow frequency ranges with equally spaced medium carrier frequencies, the filtering operation of each signal sample to form different samples from a plurality of filtered samples, includes the operation converting the sampling frequency of the signal to the total carrier frequency for all different narrow frequency ranges, and the operation of selecting at least one identified sample from the set of filtered samples, as selected The signal with a reduced radio noise on the main channel includes the step of converting the frequency of each selected filtered sample to return to the original carrier frequency.  13. A method of reducing radio interference along the main channel in samples of a signal of a frequency band of modulating signals in a given frequency band, which includes the following operations: filtering the signal samples to form from each signal sample a plurality of filtered samples representing the components of the signal sample in at least three different narrow ranges with a uniform spacing of carrier frequencies within a given frequency band, and the filtering operation to form various samples from the set of filtered samples rock, including the step of converting the sampling frequency of the signal to the common carrier frequency for all of the different narrow frequency bands; identification of one of the many filtered samples having a maximum instant energy; the selection of at least one identified sample from the set of filtered samples, as a sample signal having reduced radio interference on the main channel, the selection stage includes the step of converting the frequency of each selected filtered sample and returning it to the original carrier frequency.  14. The method in accordance with any of paragraphs. 9-13, in which the filtering operation for forming each of the plurality of filtered samples includes a filtering operation in accordance with the angular function of the elongated spheroid. 15. The method in accordance with any one of claims 1 to 8, further comprising the following delay of the signal samples by two sampling periods to obtain three consecutive samples s (kl), s (k) and s (k + 1) and generating a demodulating signal by defining at least the real part of the expression

where s * (kl) and s * (k) are the conjugate functions s (kl) and s (k), respectively.  16. The method in accordance with clause 15, in which the operation of creating a demodulating signal follows the operation of limiting each sample. 17. The method in accordance with any one of claims 9-14, further comprising delaying the samples of the signal by two sampling periods to create three consecutive samples s (kl), s (k) and s (k + 1) and generating a demodulating signal, determining at least the real part of the expression

where s * (k-1) and s * (k) are the conjugate functions s (kl) and s (k), respectively.  18. The method according to claim 17, wherein the step of creating a demodulating signal follows filtering the samples to obtain a plurality of filtered samples. 19. A method for processing samples of a frequency-modulated signal, including the following operations: delaying the samples of the signal by two sampling periods to obtain three consecutive samples s (k-1), s (k) and s (k + l) and generating a demodulating signal, determining at least the real part of the expression

where s * (k-1) and s * (k) are the conjugate functions s (kl) and s (k), respectively.  20. The method in accordance with any of paragraphs.15-19, further comprising the operation of determining the structure of the demodulating signal to create the specified signal.  21. The method in accordance with any of paragraphs.15-20, further comprising the following operations: filtering the samples of the signal in a non-stationary null filter for a useful signal to obtain samples of the error signal; determination of non-stationary coefficients for a null filter depending on the demodulating signal; subtracting the mismatch error from the signal sample to obtain output signal samples.  22. A programmable digital signal processor that implements the method according to any one of claims 1 to 21.  23. A device for reducing radio noise on the main channel in the samples of a complex signal in a frequency-modulated signal in a given frequency band of modulating signals, comprising: a complex signal limiter and a non-linear filter for obtaining non-linear filtered and limited signal samples; a selective filter into which nonlinear filtered limited samples are fed to obtain maximum instantaneous energy of signal samples from different parts of the frequency band at different times; a nonlinear conversion unit for obtaining a demodulating signal from samples of a signal with maximum instantaneous energy obtained from a selective filter; a null filter that responds to a demodulating signal to obtain non-stationary coefficients of the null filter and to separate the useful signal from the radio noise along the main channel in non-linear filtered and limited signal samples.  24. A device for reducing radio interference on the main channel in the samples of a complex signal x (k) in a given frequency band of modulating signals, comprising: a complex signal limiter (20) to obtain limited samples of the signal x (k) / | x (k) | from samples of the complex signal x (k); low pass filter (21) for filtering limited samples.  25. The device in accordance with paragraph 24, further comprising a non-linear filter for non-linear filtering of samples coming from the output of the low-pass filter, to obtain non-linear filtered samples having reduced radio noise on the main channel.  26. The device according to claim 25, wherein the non-linear filter comprises a first multiplier (23) for obtaining a first product of each filtered limited sample of the signal from the output of the low-pass filter and its associated function; a high-pass filter (24) to remove the DC component from the first product; a second multiplier (25) to obtain a second product of each filtered limited sample of the signal and the first product of the high-pass filter; chain (26) for obtaining the difference between each filtered limited sample of the signal and the second product; low-pass filter (27) to filter the specified difference.  27. The device in accordance with any one of paragraphs.24-26, comprising a selective filter, comprising: a filter (40) for filtering signal samples and generating from each signal sample a plurality of filtered samples representing components of the signal sample in various narrow ranges of a given frequency band ; a selector, maximum energy (47) to identify one of the many filtered samples having maximum instantaneous energy; a selector (44) for selecting at least one identified sample from a plurality of filtered signal samples having attenuated radio interference along the main channel.  28. The device in accordance with clause 27, in which limited samples are received on the selective filter.  29. A device for reducing radio interference on the main channel with complex samples of useful in a given frequency band in a received signal in a communication system, comprising: a filter (40) for filtering signal samples to form from each signal sample a plurality of filtered samples representing components of the signal sample in various narrow ranges within a given frequency band; a maximum energy selector (47) for identifying one of a plurality of filtered samples having a maximum instantaneous energy; a selector (44) for selecting at least one identified sample from a plurality of filtered samples having attenuated radio interference along the main channel.  30. A device in accordance with any one of claims 27-29, wherein the selective filter comprises a converter (42) for converting the sample frequency of the signal to a common carrier frequency for all different narrow frequency ranges and a converter (45) for converting the frequency of each filtered sample, selected by the selector, back to its original carrier frequency.  31. The device in accordance with any one of paragraphs.27-30, in which each filter (40) contains the angular function of an elongated spheroid. 32. The device in accordance with any of paragraphs.24-31, further comprising: a demodulator containing delay elements for delaying the signal samples for two sampling periods and obtaining three consecutive samples s (kl), s (k) and s (k + l ) and creating a demodulating signal by determining at least the real part of the expression

where - s * (kl) and s * (k) are the conjugate functions s (kl) and s (k), respectively. 33. A device for processing samples of a frequency-modulated signal, comprising a demodulator including delay elements for delaying the samples of the signal by two sampling periods to obtain three consecutive samples s (kl), s (k) and s (k + 1) and create a demodulating signal by defining at least the real part of the expression

where - s * (k-1) and s * (k) are the conjugate functions s (kl) and s (k), respectively.  34. The device in accordance with clause 32 or 33, further comprising a node for determining the arctangent of the demodulating signal to obtain the specified signal.  35. The device in accordance with any of paragraphs.32-34, further comprising the following nodes: non-stationary filter for filtering samples of the signal depending on non-stationary coefficients to obtain samples of the error signal; a node for determining non-stationary coefficients for a null filter depending on the demodulating signal; a node for subtracting samples of the error signal from the samples of the complex signal to obtain samples of the output signal.