Systems and methods for reducing interference between a plurality of wireless communications modules

• US 8,774,722 B2
• Filed: 07/02/2010
• Issued: 07/08/2014
• Est. Priority Date: 07/09/2009
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: MediaTek, Inc.
• Inventors: Hsu, Hong-Kai, Ko, Li-Chun, Chang, Chia-Ming, Hsieh, I-Lin, Chien, Wen-Ying, Lin, Jwo-An, Tseng, Ting-Che, Chen, Yuan, Yeh, Chih-Hao, Hsia, En-Chia
• Primary Examiner(s): DEAN, RAYMOND S
• Application Number:
  US12/829,943
• Publication Number:
  US 20110009060A1
• Time in Patent Office: 1,467 Days
• Field of Search: 455/63.1, 455/67.13, 455/69, 455/522, 370/318
• US Class Current: 455/63.1
• CPC Class Codes: H04B 1/7136 Arrangements for generation of hop frequencies, e.g. using a bank of frequency sources, using continuous tuning or using a transform
• CPC Class Codes: H04B 1/715 Interference-related aspects
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 2001/7154 with means for preventing interference
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel

Abstract

A wireless communications system is provided with a first wireless communications and a second wireless communications. The first wireless communications module transmits or receives a first wireless signal in a first frequency band selected from a first frequency range. The second wireless communications module transmits or receives a second wireless signal in a second frequency band selected from a second frequency range, and adjusts a transmission power of the second wireless signal in response to that a frequency offset between the first frequency band and the second frequency band falls within a predetermined range.

Claims

1. A wireless communications system, comprising:

a first wireless communications module configured to transmit or receive a first wireless signal in a first frequency band selected from a first frequency range; and

a second wireless communications module configured to transmit or receive a second wireless signal in a second frequency band selected from a second frequency range which overlaps at least in part with the first frequency range;

wherein the first wireless communications module is further configured to determine an in-band range in the overlapping part of the first and second frequency ranges, wherein the in-band range corresponds to a frequency range where a received first wireless signal and a received second wireless signal experience in-band interference caused by a transmitted second wireless signal and a transmitted first wireless signal, respectively; and

wherein the second wireless communications module is further configured to determine whether a frequency offset between the first frequency band and the second frequency band falls within the in-band range, and adjust a transmission power of the second wireless signal in response to the frequency offset falling within the in-band range.

2. The system as claimed in claim 1, wherein the adjustment of the transmission power of the second wireless signal comprises decreasing the transmission power of the second wireless signal when the frequency offset between the first frequency band and the second frequency band is less than or equal to a predetermined threshold.

3. The system as claimed in claim 2, wherein the decreased transmission power of the second wireless signal meets a requirement so that the first wireless signal can be received by the first wireless communications module in concurrence with transmission of the second wireless signal by the second wireless communications module.

4. The system as claimed in claim 1, wherein the second frequency range comprises a plurality of hopping channels, and the adjustment of the transmission power of the second wireless signal is performed when a frequency offset between a next hopping channel of the second wireless signal and the first frequency band is within the predetermined range.

5. The system as claimed in claim 1, wherein the first frequency range comprises a plurality of hopping channels, and the adjustment of the transmission power of the second wireless signal is performed when a frequency offset between the second frequency band of the second wireless signal and a next hopping channel of the first wireless signal is within the predetermined range.

6. The system as claimed in claim 1, wherein the transmission power of the second wireless signal is adjusted according to at least the frequency offset between the first wireless signal and the second wireless signal, transceiving modulation types, or a signal indicator of the first wireless signal or the second wireless signal.

7. The system as claimed in claim 6, wherein the signal indicator includes received signal strength indications (RSSI), signal to noise ratios (SNR), adjacent channel interferences (ACI), packet error rates (PER), or bit error rates (BER).

8. The system as claimed in claim 5, wherein one of the first and second wireless communication modules determines a channel map describing information of the in-band range of the first or second wireless signal, and sends the channel map and its transceiving modulation type to the other.

9. A method for reducing interference between a plurality of wireless communications modules in a wireless communications device, comprising:

transmitting or receiving a first wireless signal in a first frequency band selected from a first frequency range by a first wireless communications module, and transmitting or receiving a second wireless signal in a second frequency band selected from a second frequency range, which overlaps at least in part with the first frequency range, by a second wireless communications module;

determining an in-band range in the overlapping part of the first and second frequency ranges, wherein the in-band range corresponds to a frequency range where a received first wireless signal and a received second wireless signal experience in-band interference caused by a transmitted second wireless signal and a transmitted first wireless signal, respectively;

determining whether a frequency offset between the first frequency band and the second frequency band falls within the in-band range; and

adjusting a transmission power of the second wireless signal in response to the frequency offset falling within the in-band range.

10. The method as claimed in claim 9, wherein the adjustment of the transmission power of the second wireless signal comprises decreasing the transmission power of the second wireless signal when the frequency offset between the first frequency band and the second frequency band is less than or equal to a predetermined threshold.

11. The method as claimed in claim 10, wherein the decreased transmission power of the second wireless signal meets a requirement so that the first wireless signal can be received by the first wireless communications module in concurrence with transmission of the second wireless signal by the second wireless communications module.

12. The method as claimed in claim 9, wherein the second frequency range comprises a plurality of hopping channels, and the adjustment of the transmission power of the second wireless signal is performed when a frequency offset between a next hopping channel of the second wireless signal and the first frequency band is within the predetermined range.

13. The system as claimed in claim 9, wherein the transmission power of the second wireless signal is adjusted according to the frequency offset between the first wireless signal and the second wireless signal, transceiving modulation types, or a signal indicator of the first wireless signals or the second wireless signals.

14. The system as claimed in claim 13, wherein the signal indicator includes received signal strength indications (RSSI), signal to noise ratios (SNR), adjacent channel interferences (ACI), packet error rates (PER), or bit error rates (BER).