Wi-Fi HaLow (802.11ah) Guide
Wi-Fi HaLow takes standard 802.11ac Wi-Fi and scales the clock down 10× into the sub-1GHz band. The result is native IP networking, up to 15+ Mbps throughput, and kilometers of wall-penetrating reach. Here is how channelization, throughput, and 915 MHz coexistence work.
01 · The 10× Down-Clocking Physics
Standard 2.4 GHz and 5 GHz Wi-Fi uses 20 MHz wide channels. Wi-Fi HaLow takes that identical orthogonal frequency-division multiplexing (OFDM) structure, divides the clock by 10, and runs it between 850 MHz and 950 MHz:
- A 20 MHz Wi-Fi channel becomes a 2 MHz HaLow channel.
- Narrowing channel bandwidth by 10× drops the receiver noise floor by 10 dB, instantly tripling line-of-sight range.
- Moving from 2.4 GHz down to 915 MHz cuts free-space path loss by another 8.5 dB and eliminates foliage absorption.
- Unlike LoRa, HaLow speaks native TCP/IP, UDP, IPv6, and WPA3 security. Remote nodes have real IP addresses on your home network.
02 · Throughput vs. Range Across Bandwidths
In HaLow, you choose channel width based on whether you need a trickle of sensor telemetry at 2 miles or live video streaming at 800 meters:
| Channel Width | Long-Range Rate (MCS0) | Peak Rate (MCS7) | Practical Range | Field Application |
|---|---|---|---|---|
| 1 MHz | 150 – 300 kbps | 3.0 – 4.0 Mbps | 1.5 – 3.0 km | Extreme range, battery telemetry, deep basement penetration, smart meters |
| 2 MHz | 300 – 650 kbps | 6.5 – 8.0 Mbps | 1.0 – 1.8 km | Sweet spot for 1080p IP cameras, remote gate controllers, field dashboards |
| 4 MHz | 650 kbps – 1.3 Mbps | 13.5 – 16.0 Mbps | 500 – 800 m | High-speed remote LAN bridges, multi-camera streaming, fast firmware dumps |
| 8 MHz | 1.3 – 2.7 Mbps | 27.0 – 32.0 Mbps | 200 – 400 m | Short/medium range local high-throughput links (US only; not legal in EU) |
03 · US915 Channel Grid (Complete 2, 4 & 8 MHz Rosters)
In North America, the IEEE 802.11ah standard maps the 902–928 MHz band into standardized 1 MHz, 2 MHz, 4 MHz, and 8 MHz channels. These are the exact channel numbers and center frequencies:
| Channel Number | Bandwidth | Center Freq | Frequency Span | LoRa / Z-Wave Coexistence Status |
|---|---|---|---|---|
| Channel 2 | 2 MHz | 903.0 MHz | 902.0 – 904.0 MHz | Direct overlap with LoRaWAN Sub-band 1 & 2 uplinks. Avoid if LoRa is active nearby. |
| Channel 6 | 2 MHz | 905.0 MHz | 904.0 – 906.0 MHz | Direct collision with LoRaWAN Sub-band 2 (903.9–905.3 MHz). Will deafen gateways. |
| Channel 10 | 2 MHz | 907.0 MHz | 906.0 – 908.0 MHz | Collides with Meshtastic US915 default channel (906.875 MHz). |
| Channel 14 | 2 MHz | 909.0 MHz | 908.0 – 910.0 MHz | Overlaps US Z-Wave classic home automation channel (908.4 MHz). |
| Channel 18 | 2 MHz | 911.0 MHz | 910.0 – 912.0 MHz | Mid-band channel. Clears LoRa Sub-band 2. |
| Channel 22 | 2 MHz | 913.0 MHz | 912.0 – 914.0 MHz | Overlaps Z-Wave Long Range 912 MHz channel. |
| Channel 26 | 2 MHz | 915.0 MHz | 914.0 – 916.0 MHz | Center of 915 MHz band. Clears LoRa uplinks. |
| Channel 30 | 2 MHz | 917.0 MHz | 916.0 – 918.0 MHz | Recommended Coexistence Channel: Clears LoRa Sub-band 2 by 12 MHz. |
| Channel 34 | 2 MHz | 919.0 MHz | 918.0 – 920.0 MHz | Recommended Coexistence Channel: Clean separation from both LoRa and ZWLR. |
| Channel 38 | 2 MHz | 921.0 MHz | 920.0 – 922.0 MHz | Recommended Coexistence Channel: High-performance video channel. |
| Channel 42 | 2 MHz | 923.0 MHz | 922.0 – 924.0 MHz | Upper band. Covers LoRaWAN 500k downlink Channels 0 and 1 (923.3 and 923.9 MHz). |
| Channel 46 | 2 MHz | 925.0 MHz | 924.0 – 926.0 MHz | Upper band. Overlaps LoRaWAN downlink Channels 2–4 (924.5–925.7 MHz). |
| Channel 50 | 2 MHz | 927.0 MHz | 926.0 – 928.0 MHz | Upper band edge. Overlaps LoRaWAN downlink Channels 5–7 (926.3–927.5 MHz); keep filter sharp to avoid 928 MHz out-of-band emissions. |
Bonded 4 MHz & 8 MHz Channels
| Channel Number | Bandwidth | Center Freq | Frequency Span | Bonded From 2 MHz Channels |
|---|---|---|---|---|
| Ch 8 (4M) | 4 MHz | 906.0 MHz | 904.0 – 908.0 MHz | Channels 6 + 10 (avoid near LoRa: covers the Meshtastic default 906.875 MHz) |
| Ch 16 (4M) | 4 MHz | 910.0 MHz | 908.0 – 912.0 MHz | Channels 14 + 18 (avoid near Z-Wave: covers 908.4 MHz) |
| Ch 24 (4M) | 4 MHz | 914.0 MHz | 912.0 – 916.0 MHz | Channels 22 + 26 (avoid near Z-Wave Long Range: covers 912 MHz) |
| Ch 32 (4M) | 4 MHz | 918.0 MHz | 916.0 – 920.0 MHz | Channels 30 + 34 (Recommended 4 MHz channel: clear of LoRa; Z-Wave 916 MHz and ZWLR 920 MHz only at its edges) |
| Ch 40 (4M) | 4 MHz | 922.0 MHz | 920.0 – 924.0 MHz | Channels 38 + 42 (OK away from LoRaWAN gateways: covers downlinks 923.3 and 923.9 MHz) |
| Ch 48 (4M) | 4 MHz | 926.0 MHz | 924.0 – 928.0 MHz | Channels 46 + 50 (avoid near LoRaWAN gateways: covers downlinks 924.5–927.5 MHz) |
| Ch 28 (8M) | 8 MHz | 916.0 MHz | 912.0 – 920.0 MHz | Bonded 8 MHz block (4 MHz Ch 24 + 32). Max 32 Mbps throughput. |
04 · The 915 MHz Coexistence Challenge (HaLow vs. LoRa)
In the United States, Wi-Fi HaLow and LoRa share the exact same 902–928 MHz spectrum. Because a HaLow video camera blasts 2 MHz of continuous OFDM power while a LoRa node listens for microscopic 125 kHz chirps, poor frequency planning will deafen your LoRa receivers.
How to Coexist Without Interference
Split the Band: LoRaWAN Sub-band 2 sits at 903.9–905.3 MHz, and Meshtastic defaults to 906.875 MHz. Configure your Wi-Fi HaLow Access Point to use channels above 916 MHz (e.g. 2 MHz Channel 30 @ 917 MHz, Channel 34 @ 919 MHz, or Channel 38 @ 921 MHz). That keeps 10 MHz of guard band between high-speed video and low-power mesh nodes.
Physical Separation: Never mount a Wi-Fi HaLow antenna and an SX1262 LoRa antenna on the same pole closer than 1.5 meters apart. Out-of-band phase noise from the HaLow power amplifier will desensitize the LoRa receiver front-end even if frequencies do not overlap.
05 · Available Silicon & Breakout Modules
Morse Micro MM6108
SDIO 2.0 / SPIAustralian fabless semiconductor pioneer. The MM6108 is the premier single-chip Wi-Fi HaLow SoC with integrated PA and LNA, supporting 1, 2, 4, and 8 MHz channels.
Newracom NRC7292 / NRC7394
SDIO / SPI / UARTThe original silicon behind early maker breakout boards (Alfa Tube-AH, Makerfabs HaLow, Xiao HaLow). Mature open-source Linux kernel driver support.