As wireless technologies proliferate, mobile wireless devices incorporate a multiplicity of different wireless standards. For example, a cellular telephone can accommodate a cellular network (e.g., Universal Mobile Telecommunications System (“UMTS”)), a wireless local area network (“WLAN”), such as IEEE 802.11, and a wireless personal area network (“WPAN”) (e.g., Bluetooth). Including WPAN access makes utilization of a wireless device more convenient by allowing use of wireless headsets and other short-range wireless appliances.
Some of the various wireless standards adopted for use in mobile devices employ adjacent and/or overlapping portions of the wireless spectrum. For example, both Bluetooth and IEEE 802.11b/g/n occupy the 2.45 GHz band. Such close proximity in the wireless spectrum unfortunately can lead to interference problems.
The problems noted above are solved at least in large part by, for example, a wireless device that comprises a first wireless transceiver configured for communication via a first wireless network, a second wireless transceiver configured for communication via a second wireless network; and a scheduler that controls which of the first and second transceivers is granted access to a wireless medium at a given time. When the first wireless transceiver has been granted access to the wireless medium by the scheduler and the first wireless transceiver receives a packet via the first wireless network, the scheduler temporarily grants the second wireless transceiver access to the wireless medium based on the packet indicating that first wireless transceiver is not to use the wireless medium for a period of time. Further, in some embodiments no other device in the first wireless network is informed that the first wireless transceiver no longer is granted access to the wireless medium.
In accordance with other embodiments, a method comprising granting a first wireless transceiver access to a wireless medium to communicate with a first wireless network and receiving a packet via the first wireless network. Based on the packet indicating that first wireless transceiver is not to use the wireless medium for a period of time, the method further comprises granting temporary access by a second wireless transceiver to the wireless medium to communicate with a second wireless network. Further still in some embodiments the method comprises not informing any devices on the first wireless network that the first wireless transceiver no longer is granted access to the wireless medium.
For a detailed description of exemplary embodiments of the invention, reference will now be made to the accompanying drawings in which:
Certain terms are used throughout the following description and claims to refer to particular system components. As one skilled in the art will appreciate, companies may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct electrical, wireless or optical connection, or through an indirect connection via other devices and connections.
The following discussion is directed to various embodiments of the invention. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.
The two wireless transceivers 12 and 14 shown in
Wireless device 20 also includes a wireless transceiver 12 (Transceiver 1). Transceiver 1 of wireless device 20 is configured to wirelessly send packets to and receive packets from Transceiver 1 of wireless device 10. Similarly, wireless device 22 includes a wireless transceiver 14 (Transceiver 2). Transceiver 2 of wireless device 22 is configured to wirelessly send packets to and receive packets from Transceiver 2 of wireless device 10.
To avoid the interference problem noted above, the scheduler 16 sometimes grants access to the wireless medium to one of the transceivers 12, 14 at a time, thereby precluding both transceivers from attempting to communicate simultaneously on the wireless medium. For the sake of simplicity, it is assumed that transceivers 12 and 14 cannot access the medium concurrently, but the principles discussed herein may apply even when only some current medium access is not allowed. Thus, scheduler 16 grants access to Transceiver 1 in the wireless device 10 to communicate over the wireless medium with corresponding Transceiver 1 of wireless device 20. While those communications are occurring, scheduler 16 does not grant access to the wireless medium by Transceiver 2 and thus Transceiver 2 is precluded from communicating over the wireless medium with Transceiver 2 of wireless device 22.
At other points in time, scheduler 16 instead grants access to Transceiver 2 in the wireless device 10 to communicate over the wireless medium with corresponding Transceiver 2 of wireless device 22. While those communications are occurring, scheduler 16 does not grant access to the wireless medium by Transceiver 1 and thus Transceiver 1 is precluded from communicating over the wireless medium with Transceiver 1 of wireless device 20.
In accordance with the preferred embodiments of the invention,
In other embodiments, a RTS control frame or a CTS control frame may be used to trigger the temporary switch-over to the Bluetooth transceiver.
The wireless device 10 may also receive a WLAN “TXOP” packet in which the receiver address indicates that another pair of devices in the WLAN are exchanging packets over a known time duration (e.g., 12 milliseconds). The amount of time is encoded in the duration filed of the packet and is used, in accordance with preferred embodiments, to cause the scheduler 16 to temporarily grant the Bluetooth transceiver 12, 14 access to the wireless medium during that time period.
In some embodiments, when the scheduler 16 temporarily grants the Bluetooth transceiver 12, 14 access to the wireless medium during time period 52, no other wireless device in the WLAN is informed that the WLAN transceiver no longer is granted access to the wireless medium.
In some embodiments, the WLAN transceiver 12, 14 extracts the time period from the CTS2Self packet and sends a message to the scheduler 16 authorizing the scheduler to grant, if desired, wireless medium access to another wireless transceiver (e.g., the Bluetooth transceiver). In yet other embodiments, the scheduler 16 receives a copy of the CTS2Self packet and determines for itself that the Bluetooth transceiver can be granted temporary access to the wireless medium.
In accordance with the preferred embodiments of the invention,
The packet with FLOW bit set in this case does not indicate when the FLOW bit will be unset (i.e., the timer period 64 is not encoded in a packet), and thus the length of time period 64 is not known with certainty. However, the length of the time period 64 can be estimated. For example, the length of time period 64 can be predicted based on history information using a moving average of the time periods observed in the past. The transceivers 12, 14 or scheduler 16 measures and records the amount of time between when FLOW bits are set and then unset, computes a running average of such time intervals and uses that computed average to determine how much time to allocate to the temporary use of the wireless medium by the WLAN transceiver.
As with the WLAN-to-Bluetooth deferral, in some embodiments when the scheduler 16 temporarily grants the WLAN transceiver 12, 14 access to the wireless medium during timer period 64, no other wireless device the Bluetooth PAN is informed that the Bluetooth transceiver of wireless device 10 no longer is granted access to the wireless medium.
At 102, the method comprises granting one of the wireless transceivers access to the wireless medium to communicate with over a corresponding wireless network. For example, the scheduler 16 may grant access to the WLAN transceiver 12, 14 to communicate over its corresponding WLAN, or to the Bluetooth transceiver 12, 14 to communicate over its corresponding Bluetooth PAN. The “corresponding” wireless network thus refers to the network over which the wireless transceiver is configured to communicate.
At 104, the method further comprises receiving a packet via the wireless network corresponding to the granted wireless transceiver. At 106, the wireless device 10 (e.g., the granted transceiver 12, 14 or the scheduler 16) determines whether the received packet provides an indication that the wireless transceiver currently granted access to the wireless medium is not to use the medium for a period of time. Several examples are provided above (e.g., WLAN RTS/CTS/CTS2Self packet, WLAN data packet (TXOP), Bluetooth packet with a set FLOW bit).
If the received packet does not have an indication that the current wireless transceiver is not to use the medium, then the packet is consumed at 108 by the receiving wireless device 10. However, at 110 based on the packet indicating that wireless transceiver is not to use the wireless medium for a period of time, the method includes granting temporary access by another wireless transceiver to the wireless medium to communicate with that transceiver's own corresponding wireless network. Further, no devices on the former wireless network (i.e., the wireless network corresponding to the transceiver that just lost access to the medium) are informed that the former wireless transceiver no longer is granted access to the wireless medium.
The above discussion is meant to be illustrative of the principles and various embodiments of the present invention. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.
The present application claims priority to U.S. Provisional Patent Application No. 61/219,902, filed on Jun. 24, 2009 entitled “Method to Improve Channel Utilization in Coexisting Wireless Networks” and U.S. Provisional Patent Application No. 61/242,026, filed on Sep. 14, 2009 entitled “Method to Improve Channel Utilization in Coexisting Wireless Networks”; both of which are hereby incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
6236860 | Hagting et al. | May 2001 | B1 |
7146133 | Bahl et al. | Dec 2006 | B2 |
7406296 | Haartsen | Jul 2008 | B2 |
7945206 | Wilhelmsson et al. | May 2011 | B2 |
8160001 | Bitran | Apr 2012 | B2 |
20040259589 | Bahl et al. | Dec 2004 | A1 |
20050058151 | Yeh | Mar 2005 | A1 |
20050059347 | Haartsen | Mar 2005 | A1 |
20050152291 | Al-Harthi | Jul 2005 | A1 |
20050239497 | Bahl et al. | Oct 2005 | A1 |
20060020446 | Hamby et al. | Jan 2006 | A1 |
20060030265 | Desai et al. | Feb 2006 | A1 |
20060030266 | Desai et al. | Feb 2006 | A1 |
20060084383 | Ibrahim et al. | Apr 2006 | A1 |
20060274704 | Desai et al. | Dec 2006 | A1 |
20070060055 | Desai et al. | Mar 2007 | A1 |
20070183383 | Bitran et al. | Aug 2007 | A1 |
20070223430 | Desai et al. | Sep 2007 | A1 |
20070224936 | Desai et al. | Sep 2007 | A1 |
20080123610 | Desai et al. | May 2008 | A1 |
20080144493 | Yeh | Jun 2008 | A1 |
20080192806 | Wyper et al. | Aug 2008 | A1 |
20080207126 | Grushkevich et al. | Aug 2008 | A1 |
20090197652 | Lundstrom et al. | Aug 2009 | A1 |
20090268708 | Lambrecht | Oct 2009 | A1 |
Number | Date | Country |
---|---|---|
2005020518 | Mar 2005 | WO |
Entry |
---|
Wei-Shin Wang,Bluetooth a new era of connectivity,Sep. 2002,IEEE microwqave magazine. |
Number | Date | Country | |
---|---|---|---|
20100329202 A1 | Dec 2010 | US |
Number | Date | Country | |
---|---|---|---|
61219902 | Jun 2009 | US | |
61242026 | Sep 2009 | US |