How to Choose an Outdoor LoRa Gateway Antenna for 868/915 MHz

For documented product options, compare Outdoor LoRa Gateway Antennas.

Choosing an 868 MHz outdoor LoRa antenna with an N female interface and IP67 sealing is really five decisions: the full channel plan, the legal power ceiling, the connector and feedline, the radiation pattern against your site, and the test evidence behind the IP number. Get those right and the link works on day one. Guess at any one of them and the gateway underperforms after the installer has already left.

Short answer: write down the lowest and highest channel your gateway uses, then require an antenna documented across that whole range. Confirm connector type and gender at both ends, subtract the cable and arrestor loss, and check that antenna gain plus radio power still fits your region’s ERP/EIRP limit. Ask for the IP test evidence — “fiberglass” and “outdoor” are materials, not ratings.

RFTECH’s current public outdoor options are:

• GL868915: 868–915 MHz, 3 dBi, SMA male
• GL868F10: 868 ±10 MHz (fiberglass), SMA male

N female interfaces, higher gain, specified IP ratings and finished cable assemblies are quoted as project configurations backed by model-specific documentation.

Step 1: Confirm the full channel plan, not the frequency label

A LoRa gateway is specified by a regional channel plan, not a single centre frequency. In Europe the plan sits inside 863–870 MHz, with 868.1, 868.3 and 868.5 MHz as the three default uplink channels every EU868 device must support. In the US the plan spans 902–928 MHz. Both are defined in the LoRa Alliance regional parameters and mirrored in The Things Network’s frequency plans.

An antenna labelled “868 MHz” only tells you where it is centred. It says nothing about usable return loss at the band edges, and nothing about the compliance of the finished system.

What to do: write down the lowest and highest channel your gateway will transmit and receive on, then require the antenna record to cover that range.

• GL868915 is documented across 868–915 MHz, which suits one part number across both regional plans.
• GL868F10 is documented as 868 ±10 MHz, which suits EU868-only installations where the band is narrow and fixed.

Step 2: Check the legal ceiling before you pay for more gain

This is the step most antenna pages skip. In the 863–870 MHz band, European limits are written as e.r.p. (effective radiated power) — the radio’s output after the antenna gain and feedline loss are counted. Buying a higher-gain antenna does not raise that ceiling; it just means you have to turn the transmitter down to stay inside it.

Sub-band limits as summarised by The Things Network from ETSI EN 300 220-2. ERP and EIRP differ by the 2.15 dB gain of a reference dipole, so 14 dBm ERP is the same emission as roughly 16 dBm EIRP.

The US rule is written differently but has the same effect. Under 47 CFR 15.247, if a transmitting antenna in 902–928 MHz has directional gain above 6 dBi, the conducted output power must be reduced by the same number of dB that the gain exceeds 6 dBi — dB for dB, with only narrow exceptions for fixed point-to-point links.

Two practical consequences:

• On transmit, extra gain is not extra power. It changes the shape of the coverage, not the total permitted emission.
• On receive, extra gain still helps. There is no regulatory limit on receive sensitivity, so a high-gain antenna can improve the uplink from distant nodes even where the downlink is capped. Uplink and downlink budgets are not symmetric, and that asymmetry — not a bigger dBi number — is the honest argument for high gain.

So before specifying gain, confirm which band and sub-band you operate in, what the gateway’s conducted output power is, and who is responsible for the compliance calculation. If nobody has done that arithmetic, an 8 dBi antenna is a compliance risk rather than a coverage upgrade.

Step 3: Match the connector, the gender and the interface

Both current public RFTECH models use an SMA male connector. Requirements written as “N female” or “SMA” are incomplete until gender and polarity are pinned down:

• N-type is the usual outdoor choice: larger, more robust, easier to weatherproof. Most outdoor antennas terminate in N male, so a gateway or arrestor port that is N female mates directly, while an SMA/RP-SMA radio needs an adapter or a cable assembly.
• SMA and RP-SMA look alike and do not work together. The centre pin and socket are reversed. This single mistake accounts for a large share of “the new antenna made it worse” reports.
• Every extra interface costs signal. A lightning arrestor between gateway and antenna adds two connections plus its own insertion loss, and it brings a grounding requirement with it.

Specify connector type and gender at both ends, the arrestor model if there is one, and who supplies the adapters. Send the interface drawing when the gateway port is fixed — that way the assembly is quoted against a real interface instead of a label.

Step 4: Budget the feedline before you compare antennas

The cable is part of the antenna system. At 868 and 915 MHz, feedline loss is often larger than the difference between the two antennas you are comparing.

Use the manufacturer’s published attenuation, not a rule of thumb. As a documented reference point, the Times Microwave LMR-400 datasheet lists 3.9 dB per 100 ft at 900 MHz — about 12.8 dB per 100 m, or roughly 0.13 dB per metre. Thin cable such as RG-174 or RG-316 class is several times worse per metre; ask for the specific attenuation curve rather than accepting a generic figure.

A quick engineering estimate (not a measurement):

Read the 20 m column against the antennas you are choosing between: a 2.6 dB loss consumes almost the entire difference between a 3 dBi and a 6 dBi antenna. In other words, a shorter or better cable frequently buys more link budget than the next gain step up — and it does so without touching the ERP calculation from Step 2.

When you send a requirement, state the cable type, length and routing. A quote built on “about 20 metres of coax” is a quote built on an unknown.

Step 5: Treat IP67 as a test result, not a promise

IP ratings come from IEC 60529, and each digit is a separate test:

• 6 — dust-tight, verified in a dust chamber with no ingress permitted.
• 7 — immersion in water to 1 m depth for 30 minutes with no harmful ingress.

Two things follow, and both matter outdoors:

1. IPx7 does not imply IPx5 or IPx6. Immersion and pressurised water-jet tests are different procedures. A part that passed immersion has not necessarily been tested against driving rain at pressure or against wash-down. If the site has either, ask for a dual rating such as IP65/IP67, where both tests were passed.
2. The rating describes the tested enclosure, not the installed joint. The connector interface, the cable entry and the sealing tape are usually the first things to leak. An IP67 radome above a poorly sealed connector is still a water path into your gateway.

Fiberglass, UV resistance, wind rating and lightning protection are also separate, testable requirements. Each belongs in a quotation only when a specific model’s document supports it.

Step 6: Set gain and mounting against the real installation

Gain on an omnidirectional antenna flattens the radiation pattern toward the horizon. That helps flat, open coverage and hurts nodes directly below a tall mast or on sloped ground.

• Flat, open, long-range coverage: higher gain, mounted clear of obstructions, on a level mast.
• Urban, hilly, multi-floor, or nodes close to the mast: moderate gain such as the 3 dBi GL868915, which keeps a fuller vertical pattern.
• Any installation: height and clear line of sight usually change the result more than one or two dB of antenna gain.

For the installation review, define the mast or bracket diameter, mounting height, whether the antenna is pole-, wall- or cabinet-mounted, the cable outlet direction, the temperature range, and the wind and corrosion conditions. A coastal or industrial site changes material and sealing requirements even when the RF requirement is unchanged.

The published GL868F10 record does not state a gain figure; request the measurement data with your RFQ if that number drives the decision.

Compare documented models

The table is deliberately short: it lists what the public records support instead of padding the page with same-frequency variants. For requirements outside these two records — N female interfaces, higher gain, specified IP ratings, defined cable assemblies — RFTECH quotes against model-specific documentation and supplies the drawing or test evidence with the offer.

What a wideband part number really covers

A “868–915 MHz” antenna is not the same thing as two antennas in one. Published sub-1 GHz datasheets routinely list different peak gain and efficiency figures for the 860–876 MHz block and the 902–928 MHz block of the same part, because a single radiator tuned across roughly 70 MHz cannot be optimal at both ends.

So when a wideband part is offered, ask three questions:

1. Which band does the stated gain refer to?
2. What is the return loss or VSWR at the two band edges you actually use?
3. Is there a measurement file, or only a marketing range?

A wideband part is the right answer when you need one SKU for several regions and can accept slightly lower peak performance. A band-specific part is the right answer when the deployment is fixed and you want every dB.

Common mistakes

1. Buying by the frequency label. “868 MHz” does not confirm coverage of the full regional plan. Check the band edges.
2. Assuming gain equals range. In 863–870 MHz the limit is ERP, and in 902–928 MHz gain above 6 dBi must be offset by transmitter power. Extra gain reshapes coverage; it does not raise the ceiling.
3. Treating outdoor construction as an IP rating. Ask for the rating and the document behind it.
4. Reading IP67 as “jet-proof”. Immersion and water-jet tests are separate. Specify both if the site needs both.
5. Ordering by connector family only. Confirm gender and polarity; SMA and RP-SMA are not interchangeable.
6. Ignoring feedline loss. At 20 m even good coax can eat the difference between two gain classes.
7. Leaving the arrestor out of the plan. It adds interfaces, insertion loss and a grounding requirement.
8. Maximising gain by default. High gain narrows vertical coverage and can drop nodes near the mast.
9. Mounting low or against metal. Height and clearance usually dominate over specification differences.

What to send for an outdoor LoRa antenna RFQ

1. Target country and complete operating band, including sub-band if known.
2. Gateway radio or module, its conducted output power, and its antenna-port connector.
3. Required connector gender and any lightning-arrestor interface.
4. Feedline type, length and routing.
5. Target gain, or the coverage geometry you need and who owns the ERP/EIRP calculation.
6. Mounting method: mast, wall, cabinet, or direct to the gateway.
7. Required IP rating and whether immersion, water-jet or both must be covered, plus temperature, wind and material requirements.
8. Quantity and the datasheet, drawing or test evidence you need with the offer.

This lets the team separate a documented standard option from a project configuration, and quote each on the right basis.

FAQ

Will an 868 MHz antenna work on US915?

Not reliably. An antenna centred on 868 MHz with a ±10 MHz band does not cover 902–928 MHz. Use a part documented across both ranges, such as the GL868915, or a dedicated 915 MHz part.

Does a higher-gain antenna give me more range?

On transmit, not by itself: European limits are expressed as ERP, and US rules require power reduction above 6 dBi of gain. On receive, higher gain does help, so high gain is most useful where the uplink from distant nodes is the bottleneck.

Is a fiberglass outdoor antenna automatically IP67?

No. Fiberglass is the radome material. IP67 is a tested characteristic under IEC 60529 and must be confirmed per model.

Does IP67 mean the antenna survives pressure washing or driving rain?

Not necessarily. IP67 covers dust and temporary immersion. Water-jet protection is tested separately as IPx5 or IPx6, so ask for a dual rating if the site requires both.

Can I get an N female version?

Send the interface drawing with your requirement. The two current public models are SMA male; N female builds and cable assemblies are quoted as project configurations with the interface confirmed in writing.

Does cable length really matter at 868 MHz?

Yes. Good low-loss coax runs around 0.13 dB per metre near 900 MHz, and thin coax is several times worse. Specify the cable with the antenna and keep the run as short as the installation allows.

For the wider product family, review LoRa and LoRaWAN antennas.

Discuss an outdoor LoRa gateway project

Send your band, gateway connector and output power, feedline, mounting and environmental requirements. RFTECH will match them against the available records, supply the supporting drawing or test data, and confirm any connector or IP detail in writing before sampling or production.