Independent and concurrent automatic gain control for wireless communication and spectral intelligence

• US 9,544,041 B2
• Filed: 08/22/2013
• Issued: 01/10/2017
• Est. Priority Date: 08/22/2013
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Rangarajan, Raghuram, Kloper, David, Stager, Paul J.
• Primary Examiner(s): Urban, Edward
• Assistant Examiner(s): HU, RUI MENG
• Application Number:
  US13/973,496
• Publication Number:
  US 20150056936A1
• Time in Patent Office: 1,237 Days
• Field of Search: 455/552.1, 455/553.1, 455132-141, 4552321-2532
• US Class Current: 1/1
• CPC Class Codes: H03G 3/3078 Circuits generating control signals for digitally modulated signals
• CPC Class Codes: H04B 7/0817 with multiple receivers and antenna path selection

Abstract

A set of receiver path circuits is allocated for processing a radio-frequency (RF) signal provided by receive antennas coupled to the receiver path circuits. The RF signal may belong to a first signal class, such as Wi-Fi. A first gain control signal is applied to each of the allocated receiver path circuits to condition a signal level of the RF signal for the first signal class. A second gain control signal is applied to another set of receiver path circuits coupled to the receive antennas to condition the RF signal of a second signal class. First receive gain control signals are generated from the RF signals of the first signal class by the allocated set of the receiver path circuits. The first receive gain control signals are configured to optimize the signal level for processing the first signal class. A second receive gain control signal is generated to optimize the signal level of the RF signal for the second signal class.

Claims

1. A method comprising:

allocating, from a plurality of receiver path circuits coupled to one or more receive antennas of a wireless receiver, (i) a first set of the receiver path circuits for processing a radio-frequency (RF) signal from the receive antennas into a first receive signal of a first signal class, and (ii) a second set of the receiver path circuits for processing the RF signal into a second receive signal of a second signal class distinct from the first signal class;

first processing the first receive signal according to a wireless network protocol;

second processing the second receive signal exclusively of requirements of the wireless network protocol;

generating a first gain control signal in accordance with training data according to the wireless network protocol contained in the RF signal, and applying the first gain control signal to the first set of the receiver path circuits to condition a signal level of the RF signal for the processing thereof into the first receive signal;

generating a second gain control signal independently of generating the first gain control signal and exclusively of the training data according to the wireless network protocol, and applying the second gain control signal to the second set of the receiver path circuits to condition the signal level of the RF signal for processing thereof into the second receive signal;

reallocating at least some of the second set of the receiver path circuits to the first set of the receiver path circuits in response to a determination from the first processing that the first signal class is a wireless communication signal class associated with the wireless network protocol and the first receive signal is a wireless communication signal; and

modifying the first or second gain control signal applied to reallocated receiver path circuits to optimize the signal level of the RF signal for processing thereof into the first receive signal that is determined to be the wireless communication signal.

2. The method of claim 1, further comprising:

converting the first receive signal into a baseband signal

wherein the first processing includes processing the baseband signal according to the wireless network protocol.

3. The method of claim 2, wherein the second processing comprises performing spectral intelligence processing on the second receive signal.

4. The method of claim 1, further comprising:

determining from the wireless communication signal processed by the reallocated set of receiver path circuits that the RF signal can be classified into a second wireless communication signal class;

reallocating at least some of the second set of the receiver path circuits for processing the RF signal of the second wireless communication signal class; and

applying a third gain control signal to the reallocated receiver path circuits to optimize the signal level of the RF signal for processing thereof into the second wireless communication signal class.

5. The method of claim 4, wherein the wireless communication signal class is an IEEE 802.11 signal class and the second wireless communication signal class is a high-throughput (HT) IEEE 802.11 signal class or a very-high-throughput (VHT) signal class.

6. The method of claim 4, further comprising:

detecting an indication of an end-of-packet in the receiver signal generated from the RF signal of the second wireless communication signal class;

reallocating at least some of the first set of the receiver path circuits into the second set of the receiver path circuits;

applying the first gain control signal to the first set of the receiver path circuits to condition the signal level of the RF signal for processing into the first receive signal; and

applying the second gain control signal to the second set of the receiver path circuits to condition the signal level of the RF signal for processing into the second receive signal.

7. The method of claim 1, wherein reallocating comprises:

resetting the first or second gain control signal to a predetermined signal state for any of the receiver path circuits reallocated to process the RF signal into the wireless communication signal;

allocating the receiver path circuits for which the first or second gain control signal was reset to process the RF signal into the wireless communication signal; and

applying the third gain control signal to the receiver path reallocated to process the RF signal into the wireless communication signal.

8. The method of claim 1, wherein reallocating comprises reallocating all of the set of the second receiver path circuits in the wireless receiver to process the RF signal into the wireless communication signal.

9. The method of claim 1, wherein:

the first processing includes first processing, by a Wi-Fi processor, the first receive signal according to the wireless network protocol; and

the second processing includes second processing, by a spectrum intelligence processor, the second receive signal exclusively of the requirements of the wireless network protocol.

10. An apparatus comprising:

a set of one or more receive antennas to detect a radio frequency (RF) signal;

a plurality of receiver path circuits coupled to the receive antennas to independently process the RF signal into one or more receive signals;

a plurality of control loop circuits to convey automatic gain control (AGC) signals to and from each of the receiver path circuits; and

a processor coupled to the plurality of receiver path circuits and to plurality of control loop circuits, and configured to;

allocate (i) a first set of the receiver path circuits for processing the RF signal into a first receive signal of a first signal class, and (ii) a second set of the receiver path circuits for processing the RF signal into a second receive signal of a second signal class distinct from the first signal class;

first process the first receive signal according to a wireless network protocol;

second process the second receive signal exclusively of requirements of the wireless network protocol;

generate a first gain control signal in accordance with training data according to the wireless network protocol contained in the RF signal, and apply the first gain control signal to the first set of the receiver path circuits to condition a signal level of the RF signal for the processing thereof into the first receive signal;

generate a second gain control signal independently of generating the first gain control signal and exclusively of the training data according to the wireless network protocol, and apply a second gain control signal to the second set of the receiver path circuits to condition the signal level of the RF signal for processing thereof into the second receive signal;

reallocate at least some of the second set of the receiver path circuits to the first set of the receiver path circuits in response to a determination from the first processing that the first signal class is a wireless communication signal class associated with the wireless network protocol and the first receive signal is a wireless communication signal; and

modify the first or second gain control signal applied to reallocated receiver path circuits to optimize the signal level of the RF signal for processing thereof into the first receive signal that is determined to be the wireless communication signal.

11. The apparatus of claim 10, wherein the processor is further configured to:

determine from the wireless communication signal processed by the reallocated set of receiver path circuits that the RF signal can be classified into a second wireless communication signal class;

reallocate at least some of the second set of the receiver path circuits for processing the RF signal of the second wireless communication signal class; and

apply a third gain control signal to the reallocated receiver path circuits to optimize the signal level of the RF signal for processing thereof into the second wireless communication signal class.

12. The apparatus of claim 10, wherein the wireless communication signal class is an IEEE 802.11 signal class and the second wireless communication signal class is a high-throughput (HT) IEEE 802.11 signal class or a very-high-throughput (VHT) signal class.

13. The apparatus of claim 10, wherein the processor is further configured to:

detect an indication of an end-of-packet in the receiver signal generated from the RF signal of the second wireless communication signal class;

reallocate at least some of the first set of the receiver path circuits into the second set of the receiver path circuits;

apply the first gain control signal to the first set of the receiver path circuits to condition the signal level of the RF signal for processing into the first receive signal; and

apply the second gain control signal to the second set of the receiver path circuits to condition the signal level of the RF signal for processing into the second receive signal.

14. The apparatus of claim 13, wherein the processor is further configured to:

receive an indication that another receive signal of the wireless communication signal class is expected on an RF signal within a time interval;

postpone the reallocating of the receiver path circuits into the first and second sets of the receiver path circuits for at least the time interval.

15. The apparatus of claim 10, wherein the processor further includes:

a Wi-Fi processor configured to perform the first process operation; and

a spectrum intelligence processor configured to perform the second process operation.

16. A tangible, non-transitory computer-readable medium having instructions encoded thereon that, when executed by a processor, configure the processor to:

allocate (i) a first set of the receiver path circuits for processing the RF signal into a first receive signal of a first signal class, and (ii) a second set of the receiver path circuits for processing the RF signal into a second receive signal of a second signal class distinct from the first signal class;

first process the first receive signal according to a wireless network protocol;

second process the second receive signal exclusively of requirements of the wireless network protocol;

generate a first gain control signal in accordance with training data according to the wireless network protocol contained in the RF signal, and apply the first gain control signal to the first set of the receiver path circuits to condition a signal level of the RF signal for the processing thereof into the first receive signal;

generate a second gain control signal independently of generating the first gain control signal and exclusively of the training data according to the wireless network protocol, and apply a second gain control signal to the second set of the receiver path circuits to condition the signal level of the RF signal for processing thereof into the second receive signal;

reallocate at least some of the second set of the receiver path circuits to the first set of the receiver path circuits in response to a determination from the first processing that the first signal class is a wireless communication signal class associated with the wireless network protocol and the first receive signal is a wireless communication signal; and

modify the first or second gain control signal applied to reallocated receiver path circuits to optimize the signal level of the RF signal for processing thereof into the first receive signal that is determined to be the wireless communication signal.

17. The computer-readable medium of claim 16, having further instructions encoded thereon that, when executed by the processor, configure the processor to:

determine from the wireless communication signal processed by the reallocated set of receiver path circuits that the RF signal can be classified into a second wireless communication signal class;

reallocate at least some of the second set of the receiver path circuits for processing the RF signal of the second wireless communication signal class; and

apply a third gain control signal to the reallocated receiver path circuits to optimize the signal level of the RF signal for processing thereof into the second wireless communication signal class.

18. The computer-readable medium of claim 16, wherein the instructions further comprise instructions to cause the processor to:

perform the first process operation by a WiFi processor; and

perform the second process operation by a spectrum intelligence processor.