Jammer detection
An apparatus is disclosed for jammer detection. In example aspects, the apparatus includes a wireless transceiver configured to be connected to one or more antennas. The wireless transceiver is configured to translate a received signal from a first frequency to a second frequency using a reference signal to produce a translated received signal, with the reference signal including at least one frequency having an association with one or more targeted frequencies of a potential jamming signal. The wireless transceiver is also configured to convert at least a version of the translated received signal in the analog domain into a converted received signal in the digital domain. The wireless transceiver is further configured to detect that the converted received signal comprises a jamming signal based on the association and using at least one threshold and determine a jamming frequency of the jamming signal based on the frequency of the reference signal.
1 . An apparatus comprising:
a wireless transceiver configured to be connected to one or more antennas, the wireless transceiver comprising:
at least one mixer configured to translate a received signal from a first frequency to a second frequency using a reference signal to produce a translated received signal, the reference signal including at least one frequency having a frequency association with one or more targeted frequencies of a potential jamming signal, wherein a range of frequencies of the reference signal does not overlap a range of the one or more targeted frequencies of a potential jamming signal;
a converter configured to convert at least a version of the translated received signal in an analog domain into a converted received signal in a digital domain; and
a jammer detection module configured to detect that the converted received signal comprises a jamming signal based on the frequency association and using at least one threshold,
wherein the jammer detection module includes a jammer frequency determiner configured to determine a jamming frequency of the jamming signal based on the at least one frequency of the reference signal and the frequency association.
2 . The apparatus of claim 1 , wherein the frequency association comprises a selected difference between the at least one frequency of the reference signal and the one or more targeted frequencies of the potential jamming signal.
3 . The apparatus of claim 1 , wherein the frequency association comprises a relationship among the at least one frequency of the reference signal, the one or more targeted frequencies of the potential jamming signal, and a frequency of a local oscillator of an intermediate frequency portion of the wireless transceiver.
4 . The apparatus of claim 3 , wherein the frequency association relates (i) a difference between the at least one frequency of the reference signal and the one or more targeted frequencies of the potential jamming signal to (ii) the frequency of the local oscillator of the intermediate frequency portion of the wireless transceiver.
5 . The apparatus of claim 3 , wherein the wireless transceiver comprises:
a first mixer configured to translate the received signal from the first frequency to the second frequency using the reference signal to produce the translated received signal; and
a second mixer configured to translate the translated received signal from the second frequency to a third frequency to produce another translated received signal using a signal from the local oscillator having the frequency of the intermediate frequency portion of the wireless transceiver.
6 . The apparatus of claim 3 , wherein:
the first frequency corresponds to a radio frequency;
the second frequency corresponds to the frequency of the intermediate frequency portion of the wireless transceiver; and
the third frequency corresponds to a baseband frequency of the wireless transceiver.
7 . The apparatus of claim 5 , wherein the version of the translated received signal that is converted into the converted received signal comprises the other translated received signal produced by the second mixer.
8 . The apparatus of claim 1 , wherein the wireless transceiver is configured to:
detect that a sample of multiple samples of the converted received signal is part of the jamming signal, the sample corresponding to a time stamp; and
map the time stamp of the sample to a time index of the reference signal, the time index linked to the at least one frequency of the reference signal.
9 . The apparatus of claim 8 , wherein the wireless transceiver is configured to:
determine the jamming frequency of the jamming signal based on a frequency of a local oscillator signal of the wireless transceiver and the at least one frequency of the reference signal corresponding to the time index.
10 . The apparatus of claim 1 , wherein:
the converted received signal comprises multiple samples corresponding to multiple time stamps;
the at least one frequency of the reference signal corresponds to a time index of the reference signal; and
the wireless transceiver is configured to determine the jamming frequency of the jamming signal using the multiple time stamps of the multiple samples and the time index of the reference signal.
11 . The apparatus of claim 10 , wherein each sample of the multiple samples comprises at least one of:
a sample that is produced based on a low-pass filter that smooths the converted received signal; or
a sample that is produced based on a moving average of three or more samples.
12 . The apparatus of claim 10 , wherein the wireless transceiver is configured to detect that the converted received signal comprises the jamming signal by:
comparing a magnitude of a sample of the multiple samples to the at least one threshold, the sample corresponding to a time stamp of the multiple time stamps that aligns with the time index of the reference signal.
13 . The apparatus of claim 10 , wherein the wireless transceiver is configured to:
align the multiple samples of the converted received signal with the reference signal using the multiple time stamps of the converted received signal and multiple time indices of the reference signal, the multiple time indices comprising the time index;
map a time stamp of a sample that is detected to be part of the jamming signal to the time index of the reference signal;
link the time index of the reference signal to the at least one frequency of the reference signal; and
determine the jamming frequency of the jamming signal based on the at least one frequency of the reference signal responsive to the linking of the time index.
14 . The apparatus of claim 13 , wherein the wireless transceiver is configured to:
determine the jamming frequency of the jamming signal based on the at least one frequency of the reference signal and an intermediate frequency of the wireless transceiver.
15 . The apparatus of claim 13 , wherein the wireless transceiver comprises:
a modem configured to perform the detection, the alignment, the mapping, the linking, and the determination.
16 . The apparatus of claim 1 , wherein the reference signal has an ascertainable linkage between the at least one frequency and multiple time indices of the reference signal.
17 . The apparatus of claim 16 , wherein:
the multiple time indices span a time period over which the reference signal has multiple frequencies including the at least one frequency;
the multiple frequencies comprise a frequency range; and
the one or more targeted frequencies of the potential jamming signal substantially comprise the frequency range.
18 . The apparatus of claim 16 , wherein the wireless transceiver comprises:
a mixer configured to be coupled between at least one antenna of the one or more antennas and a modem; and
a signal generator coupled to the mixer and configured to:
generate the reference signal; and
couple the reference signal to the mixer to facilitate frequency translation.
19 . The apparatus of claim 18 , wherein the signal generator comprises:
an oscillator circuit comprising:
a selection circuit;
a frequency-varying local oscillator coupled to the selection circuit and configured to generate the reference signal for proximity detection or jammer detection; and
a local oscillator coupled to the selection circuit and configured to generate a local oscillator signal for wireless communication.
20 . The apparatus of claim 19 , wherein the wireless transceiver is configured to:
transmit a radar transmit signal using the at least one antenna of the one or more antennas;
receive a radar receive signal via at least one other antenna of the one or more antennas, the radar receive signal associated with the radar transmit signal and comprising a reflection signal component;
frequency translate the radar receive signal using the reference signal generated by the frequency-varying local oscillator to produce a down-converted radar receive signal, the reference signal comprising a frequency-modulated signal; and
detect the reflection signal component from the down-converted radar receive signal.
21 . The apparatus of claim 1 , wherein the wireless transceiver is configured to:
accommodate the jamming signal based on the jamming frequency.
22 . The apparatus of claim 21 , wherein the wireless transceiver is configured to accommodate the jamming signal by performing at least one of:
reducing at least one countermeasure used to counteract a potential jamming signal based on the jamming frequency;
lowering an amount of signal filtering based on the jamming frequency;
switching a communication from one frequency to another frequency;
adjusting an intermediate frequency of a receive chain; or
lowering a sampling rate of an analog-to-digital converter (ADC).
23 . An apparatus for jammer detection, the apparatus comprising:
means for translating a received signal from a first frequency to a second frequency using a reference signal to produce a translated received signal, the reference signal including at least one frequency having a frequency association with one or more targeted frequencies of a potential jamming signal, wherein a range of frequencies of the reference signal does not overlap a range of the one or more targeted frequencies of a potential jamming signal;
means for converting at least a version of the translated received signal in an analog domain into a converted received signal in a digital domain;
means for detecting that the converted received signal comprises a jamming signal based on the frequency association and using at least one threshold; and
means for determining a jamming frequency of the jamming signal based on the at least one frequency of the reference signal and the frequency association.
24 . The apparatus of claim 23 , further comprising:
means for accommodating the jamming signal based on the jamming frequency.
25 . A method for jammer detection, the method comprising:
translating a received signal from a first frequency to a second frequency using a reference signal to produce a translated received signal, the reference signal including at least one frequency having a frequency association with one or more targeted frequencies of a potential jamming signal, wherein a range of frequencies of the reference signal does not overlap a range of the one or more targeted frequencies of a potential jamming signal;
converting at least a version of the translated received signal in an analog domain into a converted received signal in a digital domain;
detecting that the converted received signal comprises a jamming signal based on the frequency association and using at least one threshold; and
determining a jamming frequency of the jamming signal based on the at least one frequency of the reference signal and the frequency association.
26 . The method of claim 25 , wherein:
the detecting comprises detecting that a sample of multiple samples of the converted received signal is part of the jamming signal, the sample corresponding to a time stamp; and
the determining comprises mapping the time stamp of the sample to a time index of the reference signal, the time index linked to the at least one frequency of the reference signal.
27 . The method of claim 26 , wherein the detecting comprises:
comparing a magnitude of the sample of the multiple samples to the at least one threshold.
28 . An apparatus comprising:
a wireless transceiver configured to be connected to one or more antennas, the wireless transceiver comprising:
a mixer configured to be coupled between at least one antenna of the one or more antennas and a modem; and
a signal generator comprising:
a selection circuit coupled to the mixer;
a frequency-varying local oscillator coupled to the selection circuit and configured to generate a reference signal for proximity detection at a first time and for jammer detection from another wireless transceiver at a second time; and
a local oscillator coupled to the selection circuit and configured to generate a local oscillator signal for wireless communication,
wherein the wireless transceiver is configured to adjust processing of the wireless communication based on the jammer detection by generating at least one of a plurality of transmission parameters that control one or more transmission attributes for wireless communication.
29 . The apparatus of claim 28 , wherein:
the frequency-varying local oscillator is configured to produce a frequency-varying signal; and
the wireless transceiver is configured to use the selection circuit to route the frequency-varying signal from the frequency-varying local oscillator to the mixer to provide the frequency-varying signal as the reference signal for jammer detection at the second time.
30 . The apparatus of claim 29 , wherein:
the frequency-varying local oscillator is configured to produce a frequency-modulated signal; and
the wireless transceiver is configured to use the selection circuit to route the frequency-modulated signal from the frequency-varying local oscillator to the mixer to provide the frequency-modulated signal as the reference signal for proximity detection at the first time.