Base Station

The base station is the operator’s interface to the SmartPot fleet. It receives telemetry from all deployed smart buoys and sends commands back to individual traps.

Core Hardware

Same as the smart buoy: Heltec Wireless Tracker v1.1 (ESP32-S3 + SX1262 + GNSS).

The base station firmware differs — it runs the fleet management interface rather than the buoy relay firmware.

Display Options

Built-in OLED (0.96”)

• Single-pot status view (cycle through pots with buttons)
• Summary stats: total pots, keepers, alerts
• Compact for handheld/pocket use

External TFT (2.4” ILI9341, optional)

• Fleet map view with pot positions
• Color-coded status indicators
• Touch input for command selection

Phone App (Future Phase)

• BLE connection from base station to phone
• Full fleet dashboard with maps
• Command interface with confirmation dialogs
• Tide-aware alerts (see below)

Fleet Management

The base station maintains a local database (NVS) of all registered pots:

Field	Type	Description
pot_id	uint16	Unique identifier
aes_key	16 bytes	Per-pot encryption key
deploy_lat	int32	Deployment latitude (1e-7 deg)
deploy_lon	int32	Deployment longitude (1e-7 deg)
last_seen	uint32	Unix timestamp of last telemetry
keeper_total	uint16	Cumulative keeper count
status	uint8	Current pot status flags

Command Interface

The operator can send any command from the Command Protocol to any pot in the fleet. Critical commands (SURFACE, LOCK_DOOR, UNLOCK_DOOR) require confirmation:

1. Operator selects pot and command
2. Base station displays confirmation prompt
3. Operator confirms
4. Command is sent with AES-CMAC authentication
5. Base station waits for ACK (up to 10s, 3 retries)
6. Result displayed to operator

Tidal Awareness

Crabbing in river mouths and estuaries is tide-driven — crabs are most active during incoming (flood) tide, with catch rates dropping roughly an hour after high tide. SmartPot provides tide-aware alerts so the operator can time pulls to the productive window instead of guessing.

Architecture

Tide logic runs entirely on the phone app, not on the ESP32 firmware. The base station’s role is limited to relaying telemetry via BLE to the phone — the base station hardware has no tide awareness of its own.

The data flow:

1. Phone GPS fix — the app reads the operator’s current position (or the centroid of deployed pot positions)
2. Station lookup — the app queries the NOAA CO-OPS Tides & Currents API for the nearest active reference station
3. Prediction fetch — the app requests tide predictions (high/low times and heights) for the next 48 hours from that station
4. Window computation — flood and ebb windows are derived from the prediction data, adjusted for any known time offset between the reference station and the actual fishing area
5. Alert generation — the app compares the current time and incoming telemetry against the computed tidal windows and fires alerts

Note

The ESP32 base station has no internet connectivity. All NOAA API calls originate from the phone over cellular or Wi-Fi. When the phone is offline, the app falls back to cached predictions from the last successful fetch — typically valid for 24-48 hours.

NOAA CO-OPS API Integration

The phone app uses two primary NOAA CO-OPS endpoints:

Station discovery — find the nearest reference station to the operator’s GPS position:

GET https://api.tidesandcurrents.noaa.gov/mdapi/prod/webapi/stations.json
    ?type=tidepredictions
    &units=english

The app filters the returned station list by distance from the phone’s GPS coordinates and selects the closest active station.

Tide predictions — fetch high/low predictions for a given station:

GET https://api.tidesandcurrents.noaa.gov/api/prod/datagetter
    ?station=8638863
    &product=predictions
    &datum=MLLW
    &units=english
    &time_zone=lst_lke
    &interval=hilo
    &begin_date=20250601
    &end_date=20250602
    &format=json
    &application=SmartPot

Tip

NOAA requires an application parameter to identify the calling software. Use SmartPot or a variant that identifies the operator’s fleet. This is not an API key — the CO-OPS API is free and unauthenticated — but NOAA uses it for usage tracking and may throttle unnamed callers.

Companion Tool: noaa-tides MCP Server

A standalone noaa-tides MCP server is in development as a companion tool for working with NOAA CO-OPS tide data outside the SmartPot phone app. This server wraps the same NOAA API endpoints and is intended for desktop-side analysis, fleet planning, and development workflows. It is not a dependency of the SmartPot system itself — the phone app handles all tide queries at runtime.

Alert Table

Alert	Trigger	Action
Flood starting	Incoming tide detected at deployment location	Notify: productive window opening
Window closing	~1 hour after local high tide	Notify: catch rates declining, consider pulling
Pot full	Keeper count hits operator-defined threshold	Notify: pot ready for recovery
Idle pot	No catch events for configurable duration	Notify: consider repositioning
Safe to soak	Pot GPS stable, no drift, good battery	Confirm: safe to leave for next tidal cycle

Because SmartPot pots are GPS-tracked and ropeless, leaving them across tidal cycles is low-risk — the system knows where every pot is and can surface any of them on demand. The operator pulls when the pot is full, not when they’re afraid of losing it.

Post-Hoc Tidal Correlation

Every catch event in the telemetry log carries a Unix timestamp. After a fishing session (or over a full season), these timestamps can be correlated with historical tidal phase data from NOAA to build a picture of catch rates relative to the tidal cycle at each deployment location. This is where the real operational value accumulates — over time, the operator learns which spots produce during which phase of the tide, turning anecdotal knowledge into verifiable data.

Caution

Tidal correlation is retrospective analysis, not real-time. The phone app does not attempt to predict catch rates from tidal phase — it only alerts on the tidal window itself. Pattern analysis across tidal phases requires exporting telemetry logs and running them against historical tide data, either manually or through tooling like the noaa-tides MCP server.

Power

• USB-C powered when on the boat (12V→5V adapter from boat electrical)
• 3.7V 3000mAh LiPo for portable use (~12 hours active, days in standby)

Antenna

• External 915/868 MHz antenna (SMA, 3dBi whip or 6dBi directional)
• Higher-gain directional antenna recommended for extended range to offshore pots
• Magnetic mount for boat-top installation