Setting Up SiReNT NTRIP Corrections on Emlid Reach

2026-04-18 · 6 min read

SiReNT is the Singapore Satellite Positioning Reference Network operated by the Singapore Land Authority. It is the national CORS network broadcasting RTK corrections that snap your Emlid Reach rover to SVY21 at centimetre accuracy. This post walks through the setup we ship to every Singapore Reach customer.

What you need before starting

• An Emlid Reach receiver — RX, RS3 or RS4 Pro all work.
• Latest Emlid Flow app on iOS or Android.
• SiReNT account (NTRIP user / password). Singapore Land Authority issues these — Easepect helps with the application and approval as part of every receiver sale.
• Mobile data on the device running Emlid Flow (cellular or tethered).

Step 1 — Connect the receiver to Emlid Flow

Power on the Reach. Open Emlid Flow → tap the Reach hardware tile and pair over Bluetooth. The receiver firmware should be current; Flow prompts for a firmware push if not.

Step 2 — Add SiReNT as an NTRIP correction source

In Emlid Flow:

1. Tap Receiver settings → Survey → Corrections.
2. Pick NTRIP as the correction source.
3. Enter the SiReNT caster details exactly as issued by SLA on your account-activation email:
   Host: the SiReNT caster IP address — published on the SLA SiReNT portal and emailed with your account credentials. (The caster is an IP, not a friendly hostname.)
   Port: 2101 (verify on your SLA notification)
   User: your-SiReNT-username
   Password: your-SiReNT-password
4. Tap Connect. Flow will pull the available mount-point list from the caster.

Note: SLA publishes the live IP, port, mount-point list and any service-windows on the official SiReNT portal. Always cross-check against that page rather than a third-party copy — IP and reference-station list can change.

Step 3 — Pick the right mount point (reference station)

SiReNT publishes a list of mount points. Each mount point is either a VRS stream or a stream tied to a specific SLA reference station. Pick from the list returned by the caster after you connect:

• VRS mount point — the caster generates a virtual reference station near your current GPS position. Best general-purpose choice across the entire Singapore footprint; the rover gets corrections tuned to its actual location. Most jobs use this.
• Single-reference-station mount points — broadcast directly from one of the named SLA reference stations published on the SiReNT portal. Pick the reference station closest to your work site (or the one specified by your project) when you want a fixed-baseline workflow or are repeating surveys at the same site.

The exact list of station names — and which is closest to your site — is on the SLA SiReNT portal. If you are unsure which reference station applies to your project, Easepect will pre-configure the right mount point at receiver handover.

Step 4 — Set the project coordinate system to SVY21

In the Emlid Flow project settings, set the output coordinate system to SVY21 (EPSG:3414). The Reach receiver continues to track GNSS in WGS84 internally; Flow applies the SVY21 transform on output. Your displayed northing / easting values will read in metres, directly comparable with cadastral and engineering drawings.

For more on why this matters, read our SVY21 explainer.

Step 5 — Wait for FIX

Watch the solution-quality indicator in Emlid Flow. The progression is typically: SINGLE → FLOAT → FIX. With clear sky and a good cellular link, FIX arrives in 5–15 seconds. With partial sky obstruction (urban canyon, near tall buildings) it can take a minute or longer to settle. If it never reaches FIX, check:

• Mobile data is actually connected (not just registered).
• The mountpoint accepts your account (case-sensitive credentials).
• Sky view is at least half open.
• You are inside the SiReNT coverage footprint (essentially all of Singapore land + immediate offshore).

Step 6 — Verify with a known control

Before any production survey, pick a known control point — a published SLA reference, a previously surveyed monument, or your own pre-staked GCP — and compare. We usually expect agreement inside 1–2 cm horizontal, 2–4 cm vertical. If the residual is materially larger, something is wrong: wrong mountpoint, wrong coordinate system, or a multipath issue at the site.

Saving the profile

Emlid Flow saves the SiReNT NTRIP profile per project. We strongly recommend creating a single SiReNT-SVY21 project preset — credentials, mountpoint, coordinate system — and cloning it for every new job. This eliminates the most common operator error: mismatched grid between the SiReNT solution and the project output.

For PIX4Dcatch users

Same principle in PIX4Dcatch: pair the Reach over Bluetooth, enter the SiReNT NTRIP credentials in PIX4Dcatch's RTK menu, set the project to SVY21. Every photo PIX4Dcatch captures inherits the centimetre-grade RTK fix — the foundation of the subsurface utility scan workflow trusted by the Singapore Land Authority.

Ship it pre-configured

Every Emlid Reach receiver Easepect ships in Singapore is delivered with the SiReNT NTRIP preset already saved. Plug in your account credentials when they arrive and you are surveying inside 30 seconds. Request a quote for a Reach receiver bundled with SiReNT setup and operator training.