Dynamic antenna calibration scheduling
Methods and systems are provided for dynamic performance of antenna calibration. To ensure channel reciprocity of downlink and uplink channels, antenna calibration must be performed with some degree of regularity. The present disclosure includes systems and methods for performing antenna calibration, wherein noise levels are determined at various subframes of wireless telecommunication frame structures as a basis for determining when the calibration signal should be transmitted in an OFDM symbol. Utilizing the disclosed systems and methods yields preferred antenna calibration, avoiding gain degradations caused by decreases in propagation performance.
1. A wireless telecommunication system for performing antenna calibration, the system comprising:
an antenna array comprising a first antenna and a second antenna; and
a computer processing component configured to:
determine, based on listening at the antenna array, a first noise level during a first guard period;
determine, based on listening at the antenna array, a second noise level during a first uplink pilot time slot;
if the first noise level does not exceed a calibration noise threshold, perform an antenna calibration operation using a first power level during a second guard period, the second guard period being subsequent to the first guard period, wherein the antenna calibration operation comprises communicating an internal pilot signal with each of the first antenna and the second antenna;
if the first noise level exceeds the calibration noise threshold and the second noise level does not exceed the calibration noise threshold, perform the antenna calibration operation using the first power level during a second uplink pilot time slot, the second uplink pilot time slot being subsequent to the first uplink pilot time slot;
if each of the first noise level and the second noise level exceeds the calibration noise threshold, perform the antenna calibration operation using a second power level during the second guard period, the second power level being greater than the first power level.
2. The system of claim 1 , wherein the first antenna is a first transmit antenna and the second antenna is a second transmit antenna.
3. The system of claim 1 , wherein the first antenna consists of a first transmit antenna element and a first receive antenna element and the second antenna consists of a second transmit antenna element and a second receive antenna element.
4. The system of claim 1 , wherein the computer processing component is an eNodeB.
5. The system of claim 1 , wherein the computer processing component is configured to communicate with one or more UEs according to the 5G protocol.
6. The system of claim 1 , wherein the antenna array comprises 64 antennas.
7. The system of claim 1 , wherein an internal uplink channel is communicated from an antenna of the antenna array to the computer processing component via a low noise amplifier.
8. The system of claim 7 , wherein the internal downlink channel is communicated from the computer processing component to an antenna of the antenna array via an amplifier, the amplifier being different than the low noise amplifier.
9. The system of claim 1 , wherein the calibration noise threshold comprises a signal to interference noise ratio, wherein the signal is the internal pilot signal.
10. The system of claim 1 , wherein if each of the first and second noise levels exceed the calibration noise threshold, and prior to performing the antenna calibration operation using the second level, the computer processing component is further configured to:
not perform the antenna calibration operation for a calibration time period;
following the expiration of the calibration time period, determine, based on listening at the antenna array, a third noise level during the second guard period;
determine, based on listening at the antenna array, a fourth noise level during the second uplink pilot time slot;
if the third noise level does not exceed the calibration noise threshold, perform an antenna calibration operation using a first power level during a third guard period, the third guard period being subsequent to the second guard period;
if the third noise level exceeds the calibration noise threshold and the fourth noise level does not exceed the calibration noise threshold, perform the antenna calibration operation using the first power level during a third uplink pilot time slot, the third uplink pilot time slot being subsequent to the second uplink pilot time slot; and
if each of the third noise level and the fourth noise level exceeds the calibration noise threshold, perform the antenna calibration operation using a second power level during the third guard period.
11. The system of claim 10 , wherein the calibration time period is 30 minutes.
12. A method for calibrating an antenna system, the method comprising:
determining, based on listening at an antenna array, a first noise level during a first guard period, the antenna array comprising a first antenna and a second antenna;
determining, based on listening at the antenna array, a second noise level during a first uplink pilot time slot;
if the first noise level does not exceed a calibration noise threshold, performing an antenna calibration operation using a first power level during a second guard period, the second guard period being subsequent to the first guard period, wherein the antenna calibration operation comprises communicating an internal pilot signal with each of the first antenna and the second antenna;
if the first noise level exceeds the calibration noise threshold and the second noise level does not exceed the calibration noise threshold, performing the antenna calibration operation using the first power level during a second uplink pilot time slot, the second uplink pilot time slot being subsequent to the first uplink pilot time slot;
if each of the first noise level and the second noise level exceeds the calibration noise threshold, performing the antenna calibration operation using a second power level during the second guard period, the second power level being greater than the first power level.
13. The method of claim 12 , wherein an internal uplink channel is communicated from an antenna of the antenna array to a computer processing component via a low noise amplifier.
14. The method of claim 13 , wherein the internal downlink channel is communicated from the computer processing component to an antenna of the antenna array via an amplifier, the amplifier being different than the low noise amplifier.
15. The method of claim 12 , wherein if each of the first and second noise levels exceed the calibration noise threshold, and prior to performing the antenna calibration operation using the second level, the method further comprises:
not performing the antenna calibration operation for a calibration time period;
following the expiration of the calibration time period, determine, based on listening at the antenna array, a third noise level during the second guard period;
determining, based on listening at the antenna array, a fourth noise level during the second uplink pilot time slot;
if the third noise level does not exceed the calibration noise threshold, performing an antenna calibration operation using a first power level during a third guard period, the third guard period being subsequent to the second guard period;
if the third noise level exceeds the calibration noise threshold and the fourth noise level does not exceed the calibration noise threshold, performing the antenna calibration operation using the first power level during a third uplink pilot time slot, the third uplink pilot time slot being subsequent to the second uplink pilot time slot; and
if each of the third noise level and the fourth noise level exceeds the calibration noise threshold, performing the antenna calibration operation using a second power level during the third guard period.
16. The method of claim 15 , wherein the calibration time period is 30 minutes.
17. The method of claim 15 , wherein the calibration time period is inversely correlated with a calibration trigger frequency, the calibration trigger frequency being a number of times that the internal uplink channel is different than an internal downlink channel during a predetermined time.
18. A non-transitory computer storage media storing computer-usable instructions that, when used by one or more processors, cause the one or more processors to:
determine, based on listening at an antenna array, a first noise level during a first guard period;
determine, based on listening at the antenna array, a second noise level during a first uplink pilot time slot;
if the first noise level does not exceed a calibration noise threshold, perform an antenna calibration operation using a first power level during a second guard period, the second guard period being subsequent to the first guard period, wherein the antenna calibration operation comprises communicating an internal pilot signal with each of the first antenna and the second antenna;
if the first noise level exceeds the calibration noise threshold and the second noise level does not exceed the calibration noise threshold, perform the antenna calibration operation using the first power level during a second uplink pilot time slot, the second uplink pilot time slot being subsequent to the first uplink pilot time slot; and
if each of the first noise level and the second noise level exceeds the calibration noise threshold, perform the antenna calibration operation using a second power level during the second guard period, the second power level being greater than the first power level.
19. The non-transitory computer storage media of claim 18 , wherein if each of the first and second noise levels exceed the calibration noise threshold, and prior to performing the antenna calibration operation using the second level, the processor is further configured to:
not perform the antenna calibration operation for a calibration time period;
following the expiration of the calibration time period, determine, based on listening at the antenna array, a third noise level during the second guard period;
determine, based on listening at the antenna array, a fourth noise level during the second uplink pilot time slot;
if the third noise level does not exceed the calibration noise threshold, perform an antenna calibration operation using a first power level during a third guard period, the third guard period being subsequent to the second guard period;
if the third noise level exceeds the calibration noise threshold and the fourth noise level does not exceed the calibration noise threshold, perform the antenna calibration operation using the first power level during a third uplink pilot time slot, the third uplink pilot time slot being subsequent to the second uplink pilot time slot; and
if each of the third noise level and the fourth noise level exceeds the calibration noise threshold, perform the antenna calibration operation using a second power level during the third guard period.
20. The non-transitory computer storage media of claim 19 , wherein the calibration time period is inversely correlated with a calibration trigger frequency the calibration trigger frequency being a number of times that the internal uplink channel is different than an internal downlink channel during a predetermined time.