Channelization scheme for wireless local area networks

• US 7,272,358 B2
• Filed: 07/31/2002
• Issued: 09/18/2007
• Est. Priority Date: 03/07/2002
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Batra, Anuj, Shoemake, Matthew B., Anim-Appiah, Kofi
• Primary Examiner(s): Eng; George
• Assistant Examiner(s): PHAN, HUY Q
• Application Number:
  US10/210,626
• Publication Number:
  US 20030171115A1
• Time in Patent Office: 1,875 Days
• Field of Search: 455/41.2, 455/434, 455/524, 455/561, 455/526, 455/42
• US Class Current: 455/41.2
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A four channel wireless network channelization scheme is described that is particularly usable in the ISM frequency band between 2400 MHz and 2483.5 MHz. The preferred channelization scheme permits access points to be set at one of four frequencies in the ISM band, not three as taught by the IEEE 802.11b standard. This channelization scheme takes advantage of the fact that only 20 MHz is typically needed between adjacent access point channels, not 25 MHz as is taught by the 802.11b standard. With four channels to choose from, a higher density of access points can be located thereby accommodating a higher density of users. The four channels preferably are 2407, 2427, 2447 and 2467 MHz. With this selection of channel frequencies and given the current FCC regulations, all four channels can be used to transmit an equal amount of power.

Claims

1. A wireless network operating in the ISM frequency band between 2400 MHz and 2483.5 MHz, comprising:

a plurality of access points to which wireless devices communicate;

each access point programmable to a first channelization scheme and a second channelization scheme,

wherein the first channelization scheme comprises a three channel channelization scheme in which no more than three access points operate within range of each other; and

wherein for the second channelization scheme, each access point can be set to a carrier frequency selected from a group of four frequencies consisting of a first frequency, a second frequency, a third frequency and a fourth frequency,

wherein, for the second channelization scheme, the first frequency is between 2406.938 MHz and 2407.062 MHz, inclusive, the second frequency is between 2426.938 MHz and 2427.062 MHz, inclusive, the third frequency is between 2446.938 MHz and 2447.062 MHz, inclusive, and the fourth frequency is between 2466.938 MHz and 2467.062 MHz, inclusive;

wherein the wireless network is IEEE 802.11 based network;

wherein, for the second channelization scheme, four access points can operate within range of each other.

2. The wireless network of claim 1 wherein the first frequency is 2407 MHz.

3. The wireless network of claim 1 wherein the second frequency is 2427 MHz.

4. The wireless network of claim 1 wherein the third frequency is 2447 MHz.

5. The wireless network of claim 1 wherein the fourth frequency is 2467 MHz.

6. The wireless network of claim 1 wherein the first frequency is 2407 MHz, the second frequency is 2427 MHz, the third frequency is 2447 MHz, and the fourth frequency is 2467 MHz.

7. The wireless network of claim 1 wherein the first channel channelization scheme comprises three channels each having a carrier frequency, the lowest carrier frequency of which is 2412 MHz.

8. The access point of claim 1 wherein the three channel channelization scheme comprises three channels each having a carrier frequency, the lowest carrier frequency for which is 2412 MHz.

9. An access point usable in a wireless network operating in the ISM frequency band between 2400 MHz and 2483.5 MHz, comprising:

an antenna to permit communications with a wireless device; and

an interface to a wire-based network;

wherein the access point implements one of a three channel channelization scheme and a four channel channelization scheme, wherein for the four channel channelization scheme, the access point can be set to a carrier frequency selected from a group of four frequencies consisting of a first frequency, a second frequency, a third frequency and a fourth frequency;

wherein, for the four channel channelization scheme, the first frequency is between 2406.938 MHz and 2407.062 MHz, inclusive, the second frequency is between 2426.938 MHz and 2427.052 MHz, inclusive, the third frequency is between 2446.938 MHz and 2447.062 MHz, inclusive, and the fourth frequency is between 2466.938 MHz and 2467.062 MHz, inclusive;

wherein the wireless network is IEEE 802.11 based network;

wherein, for the three channel channelization scheme, no more than three access points can operate within range of each other, and for the four channel channelization scheme, four access points can operate within range of each other.

10. The access point of claim 9 wherein the first frequency is 2407 MHz.

11. The access point of claim 9 wherein the second frequency is 2427 MHz.

12. The access point of claim 9 wherein the third frequency is 2447 MHz.

13. The access point of claim 9 wherein the fourth frequency is 2467 MHz.

14. The access point of claim 9 wherein the first frequency is 2407 MHz, the second frequency is 2427 MHz, the third frequency is 2447 MHz, and the fourth frequency is 2467 MHz.

15. A communication device, comprising:

means for programming the communication device to operate in accordance with a three or a four channel channelization scheme;

wherein for the four channel channelization scheme, a carrier frequency is selected from a group of four frequencies consisting of a first frequency, a second frequency, a third frequency and a fourth frequency;

wherein, for the four channel channelization scheme, the first frequency is between 2406.938 MHz and 2407.062 MHz, inclusive, the second frequency is between 2426.938 MHz and 2427.062 MHz, inclusive, the third frequency is between 2446.938 MHz and 2447.062 MHz, inclusive, and the fourth frequency is between 2466.938 MHz and 2467.062 MHz, inclusive;

wherein the communication device is configured to operate in IEEE 802.11 based wireless networks;

wherein, for the three channel channelization scheme, no more than three communication devices can operate within range of each other, and for the four channel channelization scheme, four communication devices can operate within range of each other.

16. The communication device of claim 15 wherein the first frequency is 2407 MHz.

17. The communication device of claim 15 wherein the second frequency is 2427 MHz.

18. The communication device of claim 15 wherein the third frequency is 2447 MHz.

19. The communication device of claim 15 wherein the fourth frequency is 2467 MHz.

20. The communication device of claim 15 wherein the first frequency is 2407 MHz, the second frequency is 2427 MHz, the third frequency is 2447 MHz, and the fourth frequency is 2467 MHz.