RTK

An Android-based RTK (Real-Time Kinematic) positioning and data transmission solution, supporting NMEA parsing, RTK core algorithms, and transport layer implementations (generic + BLE). This project is designed with a modular architecture, allowing flexible composition and integration.

Features

• NMEA Support: Parse and generate NMEA sentences (GGA, RMC, etc.)
• RTK Core Module: Encapsulates RTK positioning logic, state management, and command interactions
• Multiple Transport Options:
• rtk-transport: Generic transport layer
• rtk-transport-ble: BLE (Bluetooth Low Energy) transport
• Built with Kotlin + Coroutines, extensible and easy to integrate

Installation

Available via JitPack.

1.Add JitPack repository

In your project’s settings.gradle.kts:

dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
        maven { url 'https://jitpack.io' }
    }
}

2.Add dependencies

In app/build.gradle.kts:

Option A: Import individual modules

dependencies {
    // NMEA parsing module
    implementation("com.github.lf7817.rtk:nmea:v1.0.0")

    // Core module
    implementation("com.github.lf7817.rtk:rtk-core:v1.0.0")

    // Generic transport module
    implementation("com.github.lf7817.rtk:rtk-transport:v1.0.0")

    // BLE transport module
    implementation("com.github.lf7817.rtk:rtk-transport-ble:v1.0.0")
}

Option B: Import the full package

dependencies {
    implementation("com.github.lf7817:rtk:v1.0.0")
}

Use a released tag (e.g. v1.0.0) or master-SNAPSHOT for the latest build.

Usage Guide

1. Initialize Transport and RTK Manager

val transport = RtkTransportBle(context, scope)
val rtkManager = RtkManager(scope, transport)

2. Connect to BLE Device

transport.connect(
    address,
    serviceUuid,
    writeCharacteristicUuid,
    notifyCharacteristicUuid,
    expiredMtu
)

3. Connect to NTRIP Server(Auto-Reconnect)

rtkManager.connect(
    ntripConfig,
    reconnectIntervalMs = 3000L,
    ggaTimeoutMs = 30_000L
)

4. Collect NMEA Messages

scope.launch {
    rtkManager.nmeaMessages.collect {
        Log.d("RTKManager", "Received NMEA: $it")
    }
}

5. Disconnect

rtkManager.disconnect()

6.Monitor NTRIP & Transport Connection State

// NTRIP connection state
rtkManager.connectionState.collect { state ->
    when (state) {
        ConnectionState.CONNECTED -> println("NTRIP connected")
        ConnectionState.CONNECTING -> println("Connecting to NTRIP server...")
        ConnectionState.DISCONNECTED -> println("NTRIP disconnected")
    }
}

// Transport (BLE/Serial) connection state
transport.connectionState.collect { state ->
    when (state) {
        ConnectionState.CONNECTED -> println("Transport connected")
        ConnectionState.CONNECTING -> println("Connecting to transport...")
        ConnectionState.DISCONNECTED -> println("Transport disconnected")
    }
}

Modules

• nmea: NMEA sentence parsing and generation
• rtk-core: Core RTK positioning logic (includes RtkManager)
• rtk-transport: Transport abstraction layer (e.g., serial, TCP)
• rtk-transport-ble: BLE (Bluetooth Low Energy) transport implementation