BECKHOFF DK9222-1109-0015 User Manual

Page 5

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I/O

Wireless Automation

Application Note DK9222-1109-0015

2412

2417

2422

2427

2432

2437

2442

2447

2452

2457

2462

2467

2472

1

2

3

4

5

6

7

8

9

10

11

2402

2407

Channel:

MHz

Fig.  Overlapping of WLAN channels – only 1, 6 and 11 are possible in parallel

If​radio​systems​with​the​same​frequency​are​operated​at​the​same​time​and​in​the​same​place,​interference​can​occur.​In​
order​to​prevent​this,​most​systems​have​several​separate​transmission​channels​(e.g.​WLAN​and​IEEE​802.15.4),​so​that​the​
user​can​operate​the​systems​in​parallel.​The​eleven​WLAN​radio​channels​are​arranged​in​an​overlapping​manner.​Therefore,​
only​channels​1,​6​and​11​can​be​operated​independently​in​parallel​(see​fig.​3).​Corresponding​free​frequency​ranges​are​then​
available​for​the​channels​of​the​KM6551,​so​that​both​can​be​operated​in​parallel.​In​the​following​example​(fig.​4),​CU8890​
WLAN​Controllers​with​eleven​channels​transmit​in​the​same​range​as​KM6551​units​with​16​channels.​The​channels​can​be​
freely​set​in​both​the​CU8890​and​the​KM6551,​allowing​several​systems​to​be​operated​simultaneously.

2400

2483,5

2405 2410 2415 2420 2425 2430 2435 2440 2445 2450 2455 2460 2465 2470 2475 2480

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

2400 MHz

2412 MHz

2437 MHz

2462 MHz

22 MHz

CU8890

(WLAN)

KM6551

(IEEE 802.15.4)

2

Frequency in MHz

Channels

Channel 1

Channel 6

Channel 11

Fig.  Parallel operation of WLAN (CU8890) and IEEE 802.15. (KM6551)

New Automation Technology

Beckhoff

5

For​application​notes​see​disclaimer​on​the​last​page

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