Arduino with Neo6m GPS Module

One of the major applications of electronics is its use in geolocations using a GPS (global positioning system). In this tutorial, we will explore how a GPS works, how to use the Neo6m GPS module with the Arduino and how to fix errors with this module.

How does a GPS work?

A GPS (Global Positioning System) works by utilizing a network of satellites that orbit the Earth to determine the precise location of a GPS receiver anywhere on the planet. Here's a breakdown of how it functions:

ComponentsofaGPS

1. Satellites : There are at least 24 GPS satellites orbiting the Earth at an altitude of approximately 20, 200 kilometers. These satellites are arranged in such a way that at least four satellites are visible from any point on Earth at any given time.

2. Ground Control Stations : These stations monitor and manage the satellites, ensuring they stay in the correct orbits and their signals remain accurate.

3. GPS Receivers : Devices that receive signals from the GPS satellites to determine their position on Earth. These can be found in smartphones, cars, fitness trackers, and various other devices.

How it works

1. Transmission of Signals : Each GPS satellite continuously transmits a signal containing the satellite's position and the exact time the signal was sent.

2. Signal Reception : The GPS receiver captures the signals from multiple satellites. To calculate a 2D position (latitude and longitude), a receiver needs to connect with at least three satellites. For a 3D position (latitude, longitude, and altitude), it needs signals from at least four satellites.

3. Time Delay Calculation : The GPS receiver measures the time it took for the satellite's signals to reach it. Since the signals travel at the speed of light, the receiver can calculate the distance to each satellite based on this time delay.

4. Triangulation : By knowing the distance from multiple satellites, the GPS receiver can determine its exact location through a process called trilateration. This involves solving equations to intersect the spheres of possible locations derived from each satellite's distance, pinpointing the receiver's exact location.

GPS technology is used in various applications, including navigation for vehicles and ships, mapping, surveying, tracking, and timing for various systems like cellular networks and financial transactions. For more detailed information, you can refer to sources like NASA's GPS Overview and U.S. Government's GPS Website

Hardware

The NEO-6M GPS module is a popular GPS receiver used in various electronics and DIY projects, particularly for its affordability and ease of use. Here are some key features and specifications:

1. GPS Chip : The NEO-6M module uses a U-blox NEO-6M GPS chip, which is highly sensitive (-161 dBm) and can track up to 22 satellites across 50 channels.

2. Positioning : It provides a horizontal position accuracy of approximately 2.5 meters and supports a navigation update rate of 1 Hz, with a maximum of 5 Hz.

3. Power Consumption : The module consumes around 45 mA under normal operation. It also includes a Power Save Mode (PSM) that reduces power consumption to as low as 11 mA, making it suitable for battery-operated applications like GPS wristwatches.

4. Interfaces : It communicates via UART with configurable baud rates ranging from 4800 to 230400 bps, with a default rate of 9600 bps. The module is compatible with both 3.3V and 5V logic levels, which simplifies integration with various microcontrollers, including Arduino.

5. Start Times : The NEO-6M offers a cold start time of around 27-38 seconds and a hot start time of about 1 second.

These features make the NEO-6M GPS module a versatile and efficient choice for projects that require accurate location tracking. Whether you're working on a drone, a vehicle tracking system, or a portable navigation device, this module can provide reliable GPS data with minimal power consumption.

In this tutorial we will look into how to get started with the Neo6m GPS module through a simple script which connects to a satellite and gets info on the users location, time & date.

Code

Let's go through the code step by step:

Including Libraries

The code begins by including the necessary libraries for GPS communication:

#include <TinyGPS++.h>
#include <SoftwareSerial.h>

• #include <TinyGPS++.h> Includes the TinyGPS++ library for parsing NMEA sentences from the GPS module.
• #include <SoftwareSerial.h> Includes the SoftwareSerial library, which allows serial communication on digital pins other than the default RX and TX pins of the Arduino.
• Look at the gallery below to see how to install the TinyGPS++ Library

Initializing Variables

The code declares constants and objects required for GPS communication:

static const int TXPin = 4, RXPin = 3;
static const uint32_t GPSBaud = 9600;
// The TinyGPS++ object
TinyGPSPlus gps;
// The serial connection to the GPS device
SoftwareSerial GPS(RXPin, TXPin);

• TXPin and RXPin : Define the digital pins used for transmitting (TX) and receiving (RX) data from the GPS module.
• GPSBaud : Sets the baud rate for communication with the GPS module to 9600.
• TinyGPSPlus gps : Creates an object of the TinyGPSPlus class to handle GPS data parsing.
• SoftwareSerial GPS(RXPin, TXPin) : Creates a SoftwareSerial object to handle communication with the GPS module using the defined RX and TX pins.

Setup Function

In the setup function, the serial communications are initialized:

void setup()
{
    Serial.begin(9600);
    GPS.begin(GPSBaud);
    Serial.println("Program started");
}

• Serial.begin(9600) : Initializes the serial communication at 9600 baud rate for debugging and output to the serial monitor.
• GPS.begin(GPSBaud) : Initializes the SoftwareSerial communication with the GPS module at the specified baud rate (9600).

Loop Function

The loop function continuously reads and processes GPS data:

if(GPS.available() > 0) 
{
    gps.encode(GPS.read());

    if (gps.location.isUpdated()) 
    {
        Serial.print("Latitude = ");
        Serial.print(gps.location.lat(), 6);
        Serial.print(" Longitude = ");
        Serial.print(gps.location.lng(), 6);
    }
}

• if(GPS.available() > 0) : Checks if there is data available from the GPS module.
• gps.encode(GPS.read()) : Reads a character from the GPS module and passes it to the TinyGPS++ library for parsing.
• if (gps.location.isUpdated()) : Checks if a new valid location has been parsed.
• Serial.print("Latitude = "); Serial.print(gps.location.lat(), 6); : Prints the latitude to the serial monitor with six decimal places.
• Serial.print(" Longitude = "); Serial.print(gps.location.lng(), 6); : Prints the longitude to the serial monitor with six decimal places.

This code sets up a connection with a GPS module and continuously reads and parses the data to extract and print the latitude, longitude, altitude, and satellite time information to the serial monitor.

Setting Up The Hardware

To set up the GPS sensor correctly, follow these steps:

• After uploading the code, power on the Arduino nano.
• Some GPS sensors have a power light, if you don't then don't worry and wait.
• After some time, the onboard blue led on the sensor will start blinking to indicate it has connected to the satellite network.
• When it starts blinking, reset the Arduino with the onboard button and check the serial monitor.

Note: To make this process faster and easier, sit outside, on a balcony or near a window. You could also buy a better ceramic antenna.

Note: The GPS sensor receives data in tens of NMEA packages which may or may not contain the location data that we need. In this case, if the location data is not found or not updated, nothing will be printed to the serial monitor or there will be breaks. Just relax and wait a couple of minutes for good data.