Systems and methods for detecting the presence of a transmission signal in a wireless channel
First Claim
Patent Images
1. A method for detecting the presence of a transmission signal in a wireless spectrum channel, comprising:
- converting, by a wireless device, the frequency of a signal from a first frequency to a second frequency;
filtering, by the wireless device, the signal with the second frequency to remove signals that are not within the band of the second frequency;
selecting, by the wireless device, a local oscillator frequency based in part on a frequency that is midway between two possible pilot frequencies;
using, by the wireless device, the selected local oscillator frequency to convert the signal with the second frequency to a complex baseband signal;
calculating, by the wireless device, an averaged periodogram of the complex baseband signal;
comparing, by the wireless device, a value of the averaged periodogram to a threshold; and
detecting, by the wireless device, the presence of the transmission signal, if the value of the averaged periodogram exceeds the threshold.
1 Assignment
0 Petitions
Accused Products
Abstract
A method for detecting the presence of a transmission signal in a wireless spectrum channel. The frequency of a signal is converted from a first frequency to a second frequency. The signal with the second frequency is filtered to remove signals that are not within the band of the second frequency. An averaged periodogram of the signal is calculated. A value of the averaged periodogram is compared to a threshold. The presence of the transmission signal is detected, if the value of the averaged periodogram exceeds the threshold.
16 Citations
22 Claims
-
1. A method for detecting the presence of a transmission signal in a wireless spectrum channel, comprising:
-
converting, by a wireless device, the frequency of a signal from a first frequency to a second frequency; filtering, by the wireless device, the signal with the second frequency to remove signals that are not within the band of the second frequency; selecting, by the wireless device, a local oscillator frequency based in part on a frequency that is midway between two possible pilot frequencies; using, by the wireless device, the selected local oscillator frequency to convert the signal with the second frequency to a complex baseband signal; calculating, by the wireless device, an averaged periodogram of the complex baseband signal; comparing, by the wireless device, a value of the averaged periodogram to a threshold; and detecting, by the wireless device, the presence of the transmission signal, if the value of the averaged periodogram exceeds the threshold. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A wireless device for detecting the presence of a transmission signal in a wireless spectrum channel, comprising:
-
a processor; memory in electronic communication with the processor; and instructions stored in the memory, the instructions being executable to; convert the frequency of a signal from a first frequency to a second frequency; filter the signal with the second frequency to remove signals that are not within the band of the second frequency; select a local oscillator frequency based in part on a frequency that is midway between two possible pilot frequencies; use the selected local oscillator frequency to convert the signal with the second frequency to a complex baseband signal; calculate an averaged periodogram of the complex baseband signal; compare a value of the averaged periodogram to a threshold; and detect the presence of the transmission signal, if the value of the averaged periodogram exceeds the threshold. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. An apparatus that is configured to detect the presence of a transmission signal in a wireless spectrum channel, comprising:
-
means for converting the frequency of a signal from a first frequency to a second frequency; means for filtering the signal with the second frequency to remove signals that are not within the band of the second frequency; means for selecting a local oscillator frequency based in part on a frequency that is midway between two possible pilot frequencies; means for using the selected local oscillator frequency to convert the signal with the second frequency to a complex baseband signal; means for calculating an averaged periodogram of the complex baseband signal; means for comparing a value of the averaged periodogram to a threshold; and means for detecting the presence of the transmission signal, if the value of the averaged periodogram exceeds the threshold.
-
-
22. A computer-program product for detecting the presence of a transmission signal in a wireless spectrum channel, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:
-
code for causing a wireless device to convert the frequency of a signal from a first frequency to a second frequency; code for causing the wireless device to filter the signal with the second frequency to remove signals that are not within the band of the second frequency; code for causing the wireless device to select a local oscillator frequency based in part on a frequency that is midway between two possible pilot frequencies; code for causing the wireless device to use the selected local oscillator frequency to convert the signal with the second frequency to a complex baseband signal; code for causing the wireless device to calculate an averaged periodogram of the complex baseband signal; code for causing the wireless device to compare a value of the averaged periodogram to a threshold; and code for causing the wireless device to detect the presence of the transmission signal, if the value of the averaged periodogram exceeds the threshold.
-
Specification