How AIS Signals Are Really Received on KlaipėdaTraffic.lt

When you open KlaipėdaTraffic.lt, you are not looking at a simulation or a delayed global feed. You are seeing real radio signals that ships are transmitting in the Klaipėda area right now.

🚢 1. Real air data — not ghost ships

Every AIS target you see on the map comes from real VHF radio signals broadcast by ships:

• Ships transmit AIS messages on VHF (161.975 / 162.025 MHz)
• Our antennas in Klaipėda receive those signals
• Data is sent directly to our server
• The map updates with only a few seconds delay

This means:

• No ghost ships – if the antenna doesn’t hear it, you don’t see it
• No invented positions – no “guessed” tracks to make the map look nicer
• No AIS from the other side of the world – only what is really heard around Klaipėda

If a ship switches off AIS – it disappears. If the signal is weak or blocked by buildings or terrain – it may flicker or drop out. That’s not a bug, that’s how radio works.

⏱️ 2. Why you don’t see every ship immediately

Sometimes people open the site and ask:

“Why is this ship missing?” or “Why did this ship appear later?”

The reason is simple: AIS is not a continuous stream. Ships transmit at different intervals depending on their status and speed. Typical Class A AIS behaviour looks like this:

• Underway >≈ 14 kn – position every 2–6 seconds
• Underway < 14 kn – position every 6–10 seconds
• At anchor or moored – position about every 3 minutes

So in practice:

• A ship turning in the fairway will update very often
• A ship lying quietly alongside a berth will only send a new position from time to time
• If you open the site right after a ship has transmitted, you might need to wait for the next AIS burst before it appears
• Ships behind high quays, cranes, buildings or breakwaters may temporarily drop out until the signal reaches the antenna again

Again – this is not KlaipėdaTraffic being “slow” – this is how AIS itself works.

📡 3. How KlaipėdaTraffic differs from global AIS websites

There are many AIS sites on the internet. KlaipėdaTraffic is a bit different:

🟦 Only our own antennas

We do not mix data from thousands of unknown receivers. We use our own AIS stations installed for this project in the Klaipėda area. That gives us control over quality and coverage.

🟧 Minimal delay

Global networks often route data through several servers and apply heavy processing, which can add 30–90 seconds of delay. KlaipėdaTraffic sends data straight from our receivers to the map, with very little buffering.

🟩 Port-focused tools

The whole project is built around Klaipėda port:

• Realistic drift display
• “Sail as this ship” mode
• Berth and anchorage tools
• Local overlays and fairway details

We are not trying to cover the entire world – we are trying to do one port very well.

🟥 No artificial smoothing of reality

Some services clean or smooth data to make tracks look nicer. On KlaipėdaTraffic:

• If a tugboat makes circles – you will see the circles
• If a ship drifts – you will see the drift
• If AIS drops out for a moment – you will see a gap

It is not always beautiful, but it is honest.

🌊 4. What you can expect when opening KlaipėdaTraffic.lt

• Real-time local picture of ships in and around Klaipėda
• No global clutter – only what our antennas hear
• Sometimes not every ship immediately – because AIS intervals and radio shadows exist
• Very realistic behaviour when ships turn, drift, anchor or manoeuvre

Think of it like listening on a VHF radio: if a ship doesn’t talk, we don’t hear it. If it whispers from behind a warehouse, we might hear it only sometimes.

Welcome to KlaipėdaTraffic.lt – a small local project trying to show Klaipėda port traffic as it really is, not as marketing would like it to be.