Adjusting repeater gain based on antenna feedback path loss
Technology for a repeater is disclosed. The repeater can include a first port and a second port. The repeater can include a transmitter communicatively coupled to the first port and a receiver communicatively coupled to the second port. The transmitter can transmit a path loss signal. The receiver can receive the path loss signal transmitted by the transmitter. The repeater can include a controller. The controller can identify a first power level of the signal transmitted from the transmitter. The controller can identify a second power level of the signal received at the receiver. The controller can determine an antenna feedback path loss of the repeater based on the first power level and the second power level. The controller can set a maximum gain level for the repeater based on the antenna feedback path loss to avoid an oscillation in the repeater.
1. A repeater operable to detect antenna feedback path loss, the repeater comprising:
a first port;
a second port;
a transmitter communicatively coupled to the first port, the transmitter configured to transmit a path loss signal;
a receiver communicatively coupled to the second port, the receiver configured to receive the path loss signal transmitted by the transmitter; and
a first-direction two-antenna radio frequency (RF) feedback cancellation circuit configured to be coupled between a first antenna configured to be coupled to the first antenna port and a second antenna configured to be coupled to the second antenna port to reduce feedback between the first antenna and the second antenna for a selected band in a first direction to increase the antenna feedback path loss of the repeater; or
a second-direction two-antenna RF feedback cancellation circuit coupled between the first antenna port and the second antenna port to reduce feedback for the selected band in a second direction between the second antenna and the first antenna to increase the antenna feedback path loss of the repeater; and
a controller configured to:
identify a first power level of the signal transmitted from the transmitter;
identify a second power level of the signal received at the receiver;
determine an antenna feedback path loss of the repeater based on the first power level and the second power level; and
set a maximum gain level for the repeater to be below a repeater oscillation level by a defined oscillation margin based in part on the antenna feedback path loss to avoid an oscillation in the repeater.
2. The repeater of claim 1 , wherein the repeater oscillation level is a difference between the antenna feedback path loss plus a repeater gain and the defined oscillation margin.
3. The repeater of claim 1 , further comprising:
a first direction signal path coupled between the first port and the second port;
a second direction signal path coupled between the first port and the second port;
wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
a low noise amplifier gain level on the first direction path;
a power amplifier gain level on the first direction path;
a variable attenuator attenuation level on the first direction path;
a low noise amplifier gain level on the second direction path;
a power amplifier gain level on the second direction path; or
a variable attenuator attenuation level on the second direction path.
4. The repeater of claim 1 , wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
an electrically adjustable gain level of a first antenna configured to be coupled to the first port; or
an electrically adjustable gain level of a second antenna configured to be coupled to the second port.
5. The repeater of claim 1 , wherein the controller is configured to:
increase the maximum gain level for the repeater when the antenna feedback path loss is increased while avoiding the oscillation in the repeater; or
decrease the maximum gain level for the repeater when the antenna feedback path loss is decreased.
6. The repeater of claim 1 , wherein the controller is configured to:
disable one or more radio frequency (RF) signal paths of the repeater before a maximum gain level is set; and
enable the one or more RF signal paths after the maximum gain level is set.
7. The repeater of claim 1 , wherein the controller is configured to:
determine the antenna feedback path loss and set the maximum gain level when the repeater is powered on, wherein the oscillation in the repeater is avoided when the repeater is powered on; and
determine a subsequent antenna feedback path loss and set a subsequent maximum gain level for the repeater in accordance with a defined periodicity.
8. The repeater of claim 1 , wherein the controller is configured to set the maximum gain level for the repeater in accordance with a defined pattern of antenna feedback path losses for the repeater.
9. The repeater of claim 1 , wherein the controller is configured to:
determine the antenna feedback path loss for an out-of-band signal; and
use the antenna feedback path loss for an out-of-band frequency of the out-of-band signal to determine a second antenna feedback path loss for an in-band cellular frequency.
10. The repeater of claim 1 , wherein the controller is configured to:
determine multiple antenna feedback path losses based on multiple out-of-band signals transmitted by the transmitter and received at the receiver; and
interpolate the determined multiple antenna feedback path losses to an in-band cellular frequency path loss to set the maximum gain level for the repeater.
11. The repeater of claim 1 , further comprising:
a first antenna communicatively coupled to the first port, the path loss signal being transmitted from the transmitter via the first antenna; and
a second antenna communicatively coupled to the second port, the path loss signal being received at the receiver via the second antenna.
12. The repeater system of claim 11 , further comprising a display configured to display the antenna feedback path loss of the repeater or an amount of oscillation margin available for the repeater based on the antenna feedback path loss and the maximum gain level set for the repeater to enable a user to adjust a location or a direction of one or more of the first antenna or the second antenna to increase the antenna feedback path loss of the repeater.
13. The repeater of claim 1 , wherein the repeater is one of a frequency division duplex (FDD) repeater or a time division duplex (TDD) repeater.
14. A repeater, comprising:
a first port;
a second port;
a transmitter communicatively coupled to the first port;
a receiver communicatively coupled to the second port; and
a controller configured to:
detect an oscillation in the repeater;
identify a first power level of a signal transmitted from the transmitter, wherein the signal is a licensed or unlicensed radio frequency (RF) signal;
identify a second power level of the signal received at the receiver;
determine, after the oscillation occurs in the repeater, an antenna feedback path loss of the repeater based on the first power level and the second power level, wherein the antenna feedback path loss is associated with the oscillation; and
set a maximum gain level for the repeater based in part on the antenna feedback path loss to avoid a subsequent oscillation in the repeater;
wherein the controller is configured to:
disable one or more radio frequency (RF) signal paths of the repeater before a maximum gain level is set; and
enable the one or more RF signal paths after the maximum gain level is set.
15. The repeater of claim 14 , wherein the controller is configured to set the maximum gain level for the repeater to be below a repeater oscillation level by a defined oscillation margin, wherein the repeater oscillation level is a difference between the antenna feedback path loss plus a repeater system gain and the defined oscillation margin.
16. The repeater of claim 14 , wherein the controller is configured to:
increase the maximum gain level for the repeater when the antenna feedback path loss is increased while avoiding the subsequent oscillation in the repeater; or
decrease the maximum gain level for the repeater when the antenna feedback path loss is decreased.
17. The repeater of claim 14 , further comprising:
a first direction signal path coupled between the first port and the second port;
a second direction signal path coupled between the first port and the second port;
wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
a low noise amplifier gain level on the first direction path;
a power amplifier gain level on the first direction path;
a variable attenuator attenuation level on the first direction path;
a low noise amplifier gain level on the second direction path;
a power amplifier gain level on the second direction path; or
a variable attenuator attenuation level on the second direction path.
18. The repeater of claim 14 , wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
an electrically adjustable gain level of a first antenna configured to be coupled to the first port; or
an electrically adjustable gain level of a second antenna configured to be coupled to the second port.
19. The repeater of claim 14 , further comprising:
a first-direction two-antenna radio frequency (RF) feedback cancellation circuit coupled between a first antenna configured to be coupled to the first antenna port and a second antenna configured to be coupled to the second antenna port to reduce feedback between the first antenna and the second antenna for a selected band in a first direction to increase the antenna feedback path loss of the repeater; or
a second-direction two-antenna RF feedback cancellation circuit coupled between the first antenna port and the second antenna port to reduce feedback for the selected band in a second direction between the second antenna and the first antenna to increase the antenna feedback path loss of the repeater.
20. The repeater system of claim 14 , further comprising a display configured to display the antenna feedback path loss of the repeater or an amount of oscillation margin available for the repeater based on the antenna feedback path loss and the maximum gain level set for the repeater to enable a user to adjust a location or a direction of one or more of the first antenna or the second antenna to increase the antenna feedback path loss of the repeater.
21. The repeater of claim 14 , wherein the controller is configured to determine a subsequent antenna feedback path loss and set a subsequent maximum gain level for the repeater in accordance with a defined periodicity.
22. The repeater of claim 14 , wherein the signal transmitted by the transmitter and received at the receiver is an industrial, scientific, and medical (ISM) signal or a cellular signal.
23. The repeater of claim 14 , wherein the controller is configured to:
determine the antenna feedback path loss for an out-of-band signal; and
use the antenna feedback path loss for an out-of-band frequency of the out-of-band signal to determine a second antenna feedback path loss for an in-band cellular frequency.
24. A repeater operable to detect antenna feedback path loss, the repeater comprising:
a first port;
a second port;
a transmitter communicatively coupled to the first port, the transmitter configured to transmit a path loss signal;
a receiver communicatively coupled to the second port, the receiver configured to receive the path loss signal transmitted by the transmitter;
a first-direction two-antenna radio frequency (RF) feedback cancellation circuit configured to be coupled between a first antenna configured to be coupled to the first antenna port and a second antenna configured to be coupled to the second antenna port to reduce feedback between the first antenna and the second antenna for a selected band in a first direction to increase the antenna feedback path loss of the repeater; and
a controller configured to:
identify a first power level of the signal transmitted from the transmitter;
identify a second power level of the signal received at the receiver;
determine an antenna feedback path loss of the repeater based on the first power level and the second power level; and
set a maximum gain level for the repeater based in part on the antenna feedback path loss to avoid an oscillation in the repeater.
25. The repeater of claim 24 , wherein the repeater is further comprised to determine the antenna feedback path loss for an out-of-band signal; and
use the antenna feedback path loss for an out-of-band frequency of the out-of-band signal to determine a second antenna feedback path loss for an in-band cellular frequency.
26. The repeater of claim 24 , wherein the path loss signal is an in-band cellular signal.
27. The repeater of claim 24 , further comprising:
a first direction signal path coupled between the first port and the second port;
a second direction signal path coupled between the first port and the second port;
wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
a low noise amplifier gain level on the first direction path;
a power amplifier gain level on the first direction path;
a variable attenuator attenuation level on the first direction path;
a low noise amplifier gain level on the second direction path;
a power amplifier gain level on the second direction path; or
a variable attenuator attenuation level on the second direction path.
28. The repeater of claim 24 , wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
an electrically adjustable gain level of a first antenna configured to be coupled to the first port; or
an electrically adjustable gain level of a second antenna configured to be coupled to the second port.
29. The repeater of claim 24 , further comprising:
a second-direction two-antenna RF feedback cancellation circuit coupled between the first antenna port and the second antenna port to reduce feedback for the selected band in a second direction between the second antenna and the first antenna to increase the antenna feedback path loss of the repeater.
30. The repeater of claim 24 , wherein the repeater is one of a frequency division duplex (FDD) repeater or a time division duplex (TDD) repeater.
31. A repeater operable to detect antenna feedback path loss, the repeater comprising:
a first port;
a second port;
a transmitter communicatively coupled to the first port, the transmitter configured to transmit a path loss signal;
a receiver communicatively coupled to the second port, the receiver configured to receive the path loss signal transmitted by the transmitter; and
a first direction signal path coupled between the first port and the second port; a second direction signal path coupled between the first port and the second port; a controller configured to:
identify a first power level of the signal transmitted from the transmitter;
identify a second power level of the signal received at the receiver;
determine an antenna feedback path loss of the repeater based on the first power level and the second power level; and
set a maximum gain level for the repeater to be below a repeater oscillation level by a defined oscillation margin based in part on the antenna feedback path loss to avoid an oscillation in the repeater;
wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
a low noise amplifier gain level on the first direction path;
a power amplifier gain level on the first direction path;
a variable attenuator attenuation level on the first direction path;
a low noise amplifier gain level on the second direction path;
a power amplifier gain level on the second direction path; or
a variable attenuator attenuation level on the second direction path.
32. A repeater operable to detect antenna feedback path loss, the repeater comprising:
a first port;
a second port;
a transmitter communicatively coupled to the first port, the transmitter configured to transmit a path loss signal;
a receiver communicatively coupled to the second port, the receiver configured to receive the path loss signal transmitted by the transmitter; and
a controller configured to:
identify a first power level of the signal transmitted from the transmitter;
identify a second power level of the signal received at the receiver;
determine an antenna feedback path loss of the repeater based on the first power level and the second power level; and
set a maximum gain level for the repeater to be below a repeater oscillation level by a defined oscillation margin based in part on the antenna feedback path loss to avoid an oscillation in the repeater;
wherein the controller is configured to set one or more of the following to set a system gain of the repeater:
an electrically adjustable gain level of a first antenna configured to be coupled to the first port; or
an electrically adjustable gain level of a second antenna configured to be coupled to the second port.
33. A repeater operable to detect antenna feedback path loss, the repeater comprising:
a first port;
a second port;
a transmitter communicatively coupled to the first port, the transmitter configured to transmit a path loss signal;
a receiver communicatively coupled to the second port, the receiver configured to a controller configured to:
identify a first power level of the signal transmitted from the transmitter;
identify a second power level of the signal received at the receiver;
receive the path loss signal transmitted by the transmitter; and
determine an antenna feedback path loss of the repeater based on the first power level and the second power level; and
set a maximum gain level for the repeater to be below a repeater oscillation level by a defined oscillation margin based in part on the antenna feedback path loss to avoid an oscillation in the repeater
wherein the controller is configured to set the maximum gain level for the repeater in accordance with a defined pattern of antenna feedback path losses for the repeater.