TEMPERATURE COMPENSATED CARRIER OFFSET CORRECTION OF A RECEIVED SIGNAL

• US 20150103965A1
• Filed: 12/18/2014
• Published: 04/16/2015
• Est. Priority Date: 07/06/2012
• Status: Active Grant

• Current Assignee: Nordic Semiconductor ASA
• Original Assignee: Imagination Technologies Limited (Imagination Technologies Group Ltd.)
• Inventors: Chari, Sujai
• Granted Patent: US 9,088,391 B2
• Time in Patent Office: Days
• US Class Current: 375/371
• CPC Class Codes: H04J 3/0608 Detectors therefor, e.g. correlators, state machines
• CPC Class Codes: H04L 2027/003 at baseband only
• CPC Class Codes: H04L 2027/0048 Frequency multiplication
• CPC Class Codes: H04L 2027/0095 in a preamble or similar structure
• CPC Class Codes: H04L 27/0014 Carrier regulation of chaotic carriers H04L27/001; for multicarrier receivers H04L27/2657
• CPC Class Codes: H04L 27/2657 Carrier synchronisation
• CPC Class Codes: H04L 7/042 Detectors therefor, e.g. correlators, state machines digital correlators in general G06F17/15

Abstract

Apparatuses, methods and systems for mitigating carrier offset of a received signal are disclosed. One embodiment of a receiver includes a controller operative to determine that a communication signal being received is from a desired transmitter, and to determine a carrier offset correction based on prior reception of communication signals from the desired transmitter, comprising retrieving a carrier offset of the desired transmitter from one or more stored carrier offsets based on previous communication with the desired transmitter and a temperature of the receiver. The receiver further includes a receiver chain operative to receive the communication signal from the desired transmitter, and to generate a carrier offset corrected received signal based on the retrieved carrier offset by applying the carrier offset correction to the received communication signal. The receiver is operative to synchronize to the carrier offset corrected received communication signal.

Claims

1. A receiver, comprising:

a controller operative to determine that a communication signal being received is from a desired transmitter;

the controller operative to determine a carrier offset correction based on prior reception of communication signals from the desired transmitter, comprising retrieving a carrier offset of the desired transmitter from one or more stored carrier offsets based on previous communication with the desired transmitter and a temperature of the receiver;

a receiver chain operative to receive the communication signal from the desired transmitter;

the receiver chain operative to generate a carrier offset corrected received signal based on the retrieved carrier offset by applying the carrier offset correction to the received communication signal; and

the receiver operative to synchronize to the carrier offset corrected received communication signal.

9. The receiver of claim 1, further comprising retrieving the carrier offset based on a temperature of the desired transmitter.

11. The receiver of claim 1, wherein the controller is further operative to:

estimate a first timing offset of a currently received packet of the received communication signal;

compute a second timing offset based on the determined carrier offset correction offset;

compare the estimated first timing offset with the computed second timing offset; and

determine that the currently received packet is not transmitted from the desired transmitter if an absolute value of a difference between the estimated first timing offset and the computed second timing offset is greater than a threshold.

2. The receiver of claim 2, further comprising a temperature sensor operative to sense the temperature of the receiver.

3. The receiver of claim 2, wherein the carrier offset is retrieved from memory.

4. The receiver of claim 2, wherein the one or more carrier offsets are retrieved from memory.

5. The receiver of claim 3, further comprising storing the one or more carrier offsets in memory, comprising:

sensing, by the temperature sensor, a temperature of the receiver while receiving a communication signals from the desired transmitter;

estimating the carrier offset for the desired transmitter with the receiver at the sensed temperature; and

storing the estimated carrier offset for the desired transmitter with the receiver at the sensed temperature.

6. The receiver of claim 5, further comprising storing the one or more carrier offsets in memory, comprising:

sensing, by the temperature sensor, a temperature of the receiver while receiving a communication signals from one or more other transmitters;

estimating carrier offsets for each of the one or more other transmitters with the receiver at the sensed temperature; and

storing the estimated carrier offsets for each of the one or more other transmitters with the receiver at the sensed temperature.

7. The receiver of claim 5, wherein the estimated carrier offset is stored in the memory according to ranges of sensed temperature.

8. The receiver of claim 7, wherein a number of ranges of temperature is dependent upon a variation in the carrier offset with temperature of the receiver.

10. The receiver of claim 4, further comprising aging the one or more carrier offsets of the memory, and upon a determined age, re-estimating and re-storing the one or more carrier offsets in the memory.

12. A receiver, comprising:

a controller operative to determine that a communication signal being received is from a desired transmitter;

the controller operative to determine a carrier offset correction based on prior reception of communication signals from the desired transmitter, comprising retrieving a timing offset of the desired transmitter from one or more stored timing offsets based on previous communication with the desired transmitter;

a receiver chain operative to receive the communication signal from the desired transmitter;

the receiver chain operative to calculate a carrier offset correction based on the retrieved timing offset;

the receiver chain operative to generate a carrier offset corrected received signal based on the retrieved carrier offset by applying the carrier offset correction to the received communication signal; and

the receiver operative to synchronize to the carrier offset corrected received communication signal.

13. The receiver of claim 12, further comprising:

a temperature sensor operative to sense a temperature of the receiver;

wherein the controller determining the carrier offset correction based on the prior reception of communication signals from the desired transmitter, comprises retrieving the timing offset of the desired transmitter from the one or more stored timing offsets based on the previous communication with the desired transmitter and based on the sensed temperature.

14. A method of receiving a wireless signal, comprising:

sensing, by a temperature sensor, a temperature of a receiver;

determining, by the receiver, that a communication signal being received is from a desired transmitter;

determining, by the receiver, a carrier offset correction based on prior reception of communication signals from the desired transmitter, comprising retrieving a carrier offset of the desired transmitter from one or more stored carrier offsets based on previous communication with the desired transmitter and the sensed temperature of the receiver;

receiving, by a receiver chain of the receiver, the communication signal from the desired transmitter;

generating, by the receiver chain, a carrier offset corrected received signal based on the retrieved carrier offset by applying the carrier offset correction to the received communication signal; and

synchronizing, by the receiver chain, to the carrier offset corrected received communication signal.

15. The method of claim 14, wherein the carrier offset is retrieved from memory.

16. The method of claim 14, wherein the one or more carrier offsets are retrieved from memory.

17. The method of claim 16, further comprising storing the one or more carrier offsets in memory, comprising:

sensing, by the temperature sensor, a temperature of the receiver while receiving a communication signals from the desired transmitter;

estimating the carrier offset for the desired transmitter with the receiver at the sensed temperature; and

storing the estimated carrier offset for the desired transmitter with the receiver at the sensed temperature.

18. The method of claim 17, further comprising storing the one or more carrier offsets in memory, comprising:

sensing, by the temperature sensor, a temperature of the receiver while receiving a communication signals from one or more other transmitters;

estimating carrier offsets for each of the one or more other transmitters with the receiver at the sensed temperature; and

storing the estimated carrier offsets for each of the one or more other transmitters with the receiver at the sensed temperature.

19. A method of receiving a wireless signal, comprising:

determining, by the receiver, that a communication signal being received is from a desired transmitter;

determining, by the receiver, a carrier offset correction based on prior reception of communication signals from the desired transmitter, comprising retrieving a timing offset of the desired transmitter from one or more stored timing offsets based on previous communication with the desired transmitter;

receiving, by a receiver chain of the receiver, the communication signal from the desired transmitter;

calculating a carrier offset correction based on the retrieved timing offset;

generating, by the receiver chain, a carrier offset corrected received signal based on the retrieved carrier offset by applying the carrier offset correction to the received communication signal; and

synchronizing, by the receiver, to the carrier offset corrected received communication signal.

20. The method of claim 19, further comprising:

sensing, by a temperature sensor, a temperature of the receiver;

wherein the controller determining the carrier offset correction based on the prior reception of communication signals from the desired transmitter, comprises retrieving the timing offset of the desired transmitter from the one or more stored timing offsets based on the previous communication with the desired transmitter and based on the sensed temperature.