802.11ac Channels ====================== .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What are channels in 802.11ac?** Channels in 802.11ac refer to frequency ranges in the 5 GHz band used for wireless communication, supporting wider bandwidths than 802.11a. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How many channels are available in 802.11ac?** 802.11ac supports up to 24 or more channels in the 5 GHz band, depending on regulatory domains and channel widths. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What frequency bands does 802.11ac use?** Primarily the 5 GHz band, with channel bandwidths of 20, 40, 80, and optionally 160 MHz. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What are channel widths in 802.11ac?** 802.11ac supports 20 MHz, 40 MHz, 80 MHz, and 160 MHz channel widths for higher throughput. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Why does 802.11ac support wider channels?** Wider channels allow higher data rates by transmitting more data simultaneously. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are 802.11ac channels overlapping?** Yes, depending on the channel width used, especially for 40 MHz and wider, some channel overlap occurs. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is Dynamic Frequency Selection (DFS) in 802.11ac?** DFS enables APs to detect radar signals and switch channels to avoid interference in certain 5 GHz bands. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is Transmit Power Control (TPC) in 802.11ac?** TPC manages transmission power to minimize interference and meet regulatory limits. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How are 802.11ac channels numbered?** Channels are numbered similarly to 802.11a (e.g., 36, 40, 44), but with support for wider bandwidths that combine adjacent channels. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What are typical 802.11ac channel widths and their bandwidths?** - 20 MHz: standard width - 40 MHz: combines two adjacent 20 MHz channels - 80 MHz: combines four adjacent 20 MHz channels - 160 MHz: combines eight adjacent 20 MHz channels (rarely used) .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Why is channel planning important in 802.11ac?** To minimize interference, optimize throughput, and ensure effective use of wider channels. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are all 5 GHz channels available globally for 802.11ac?** No, availability depends on local regulations, especially for DFS-required channels. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can 802.11ac devices auto-select channels?** Yes, devices typically scan and select channels to avoid congestion and interference. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What tools help with 802.11ac channel planning?** Spectrum analyzers, Wi-Fi scanners, site survey tools, and WLAN controllers. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does channel bonding affect interference in 802.11ac?** Channel bonding increases throughput but can cause more interference due to wider channels overlapping. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What happens if two APs use overlapping 80 MHz channels?** They may experience significant co-channel interference, reducing network performance. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can 802.11ac operate outdoors?** Yes, but subject to regulatory restrictions and often with DFS and TPC enabled. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the typical range of 802.11ac?** Similar to 802.11a, usually 30–50 meters indoors, varying with environment and channel width. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow Topics in this section, * :ref:`List of channels ` * :ref:`List of channel widths ` * :ref:`List of Bands ` * :ref:`Reference links ` .. _channels_ac_step4: .. tab-set:: .. tab-item:: List of channels ===================== ======================= ====================== ============== Channel Number (MHz) Center Frequency (MHz) Frequency Range (MHz) DFS Required ===================== ======================= ====================== ============== 36 5180 5170 – 5190 No 40 5200 5190 – 5210 No 44 5220 5210 – 5230 No 48 5240 5230 – 5250 No 52 5260 5250 – 5270 Yes 56 5280 5270 – 5290 Yes 60 5300 5290 – 5310 Yes 64 5320 5310 – 5330 Yes 100 5500 5490 – 5510 Yes 104 5520 5510 – 5530 Yes 108 5540 5530 – 5550 Yes 112 5560 5550 – 5570 Yes 116 5580 5570 – 5590 Yes 120 5600 5590 – 5610 Yes 124 5620 5610 – 5630 Yes 128 5640 5630 – 5650 Yes 132 5660 5650 – 5670 Yes 136 5680 5670 – 5690 Yes 140 5700 5690 – 5710 Yes 144 5720 5710 – 5730 No ===================== ======================= ====================== ============== .. _channels_ac_step5: .. tab-set:: .. tab-item:: List of channel widths * channel widths .. _channels_ac_step6: .. tab-set:: .. tab-item:: List of Bands ======================= ====================== ====================== ============================================================ Band Name Frequency Range (GHz) Frequency Range (MHz) Channels ======================= ====================== ====================== ============================================================ UNII-1 5.150 – 5.250 5150 – 5250 36, 40, 44, 48 UNII-2 (DFS) 5.250 – 5.350 5250 – 5350 52, 56, 60, 64 UNII-2 Extended (DFS) 5.470 – 5.725 5470 – 5725 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 144 UNII-3 5.725 – 5.825 5725 – 5825 149, 153, 157, 161, 165 ======================= ====================== ====================== ============================================================ .. _channels_ac_step17: .. tab-set:: .. tab-item:: Reference links * Reference links