Introduction to GPS and GPS Modules
You’re probably familiar with GPS as the ones that give you directional information through your phone, car, or on your preferred maps app. However, have you wondered what goes into it and how do these modules give you an accurate position anytime, anywhere?
When were GPS satellites launched?
GPS dates back to the late ’70s.
How do GPS modules work?
GPS modules contain tiny processors and antennas that directly receive data sent by satellites through dedicated RF frequencies. From there, it’ll receive timestamp from each visible satellites, along with other pieces of data. If the module’s antenna can spot 4 or more satellites, it’s able to accurately calculate its position and time.
Arduino GPS Modules?
I’ll be introducing and comparing two GPS modules today; NEO-6M, Grove – GPS Module. These GPS modules are compatible with Arduino and Raspberry Pi, making it easy for you to start trying it out.
Things to consider before purchasing a GPS module
|Things to consider||Rationale|
|Size||Sizing matters as it may affect things like lock time and accuracy if the antenna doesn’t fit
If your project requires it to be pocket sized, size matters as well
|Update Rate||Update rate refers to how often the GPS module recalculates and reports its position
1Hz is sufficient and the norm for most GPS module
5-10Hz update rates can be considered if you need it to work on faster vehicles
|Baud Rate||Refers to how fast data is sent over a serial line
Higher the baud rate allows for faster GPS data to be sent
|Navigation Sensitivity||dBm figure dictates how prone the gps module is able to capture the frequency
Higher dbm indicates that the module is able to better pickup satalite signals
|Power Requirements||GPS modules can consume a substantial amount of power
Average being 30mA at 3.3V
|Number of Channels||Number of channels that the module runs will affect time to first fix
More frequencies that you can check at once, allow for faster fix time
12 – 14 channels work fine for tracking if you don’t mind waiting a little longer
|Antennas||Each antenna is designed to pickup GPS L1 frequency of 1.5752 GHz
Position and design of antenna is crucial for optimal performance of GPS
|Accuracy||Lower the distance it can get down to = Higher accuracy
Usually able to find out your location within 30 seconds, down to +/- 10m
Most modules can get it down to +/-3m
Ublox GPS: NEO-6M GPS Module
Considered as one of the more popular GPS modules in the market, the NEO-6M module is a family of stand-alone GPS receivers from the NEO-6 module series.
Based on the list of considerations:
Size: 23mm x 30mm
Update Rate: 1 Hz, 5Hz maximum
- Power Supply Voltage: 3V – 5V
Baud Rate: 9600
Number of Channels: 50
Time to first start:
- Cold Start: 27s
- Warm Start: 27s
- Hot Start: 1s
- Aided Starts: <3s
Antennas: Includes external patch antenna
- 2.5m GPS Horizontal Position Accuracy
- Battery operated mobile devices
- GPS tracker
- GPS navigator
The Grove – GPS Module is Seeed version of a GPS receiver that’s cost-efficient and field-programmable. It’s armed with a SIM28 and serial communication configuration.
Size: 40mm x 20mm x 13mm
Update Rate: 1 Hz, max 10 Hz
Power Requirements: 3.3/5V
Baud Rate: 9600 – 115,200
Number of Channels: 22 trackings// 66 acquisition channels
Time to first start:
- Cold starts with EASY: 13s
- Warm Starts with EASY: 1-2s
- Hot Starts: <1s
*Easy is a self-generate orbit protection
Antennas: Antenna included in the package
Accuracy: 2.5m GPS Horizontal Position Accuracy
- GPS tracker
- GPS navigation
- Distance measurement
Other Product Features:
- Low power consumption
- Baud rates configurable
- Grove compatible interface
Ublox NEO-6M GPS Module vs Grove – GPS Module
When compared side by side:
|Things to consider||NEO-6M||Grove – GPS Module|
|Size||23mm x 30mm||40mm x 20mm x 13mm|
|Update Rate||1Hz, max 5Hz||1Hz, max 10Hz|
|Baud Rate||Default 9,600, max 230400||9,600 – 115,200|
|Power Requirements||3V – 5V||3.3/5V|
|Number of Channels||22 tracking, 50 channels||22 tracking, 66 channels|
|Time to first start||Cold start: 27s
Warm start: 27s
Hot start: 1s
|Cold start: 13s
Warm start: 1-2s
Hot start: <1s
|Antennas||External patch antenna||Antenna included|
|Accuracy||2.5m GPS Horizontal Position Accuracy||2.5m GPS Horizontal Position Accuracy|
Why Grove – GPS Module is better than the Ublox NEO-6M
Better power consumption:
Grove GPS Module uses the SIM28 chip, which offers better power consumption as compared to the u-blox 6.
With a higher maximum update rate, the Grove GPS Module is able to be used for projects that involve objects that travel at a faster speed. Furthermore, having more channels open up for other applications as well.
Pair your GPS modules with:
Seeeduino, Seeed very own Arduino Board:
Seeduino V4.2 is Seeed version of an Arduino, which can be used to pair with the Grove GPS Module and Ublox NEO-6M as well.
The base shield is designed for better ease of connecting the Grove GPS Module.
Hardware configuration :
- Connect Grove-GPS to port D2 of Grove Base Shield
- Plug Grove – Base Shield into Seeeduino
- Connect Seeeduino to PC via a USB cable
For software and further configurations, you can head here
If you do not own a raspberry pi yet, you can consider picking up a low-cost RPI Zero alongside with the Grove Base Hat to pair the Grove GPS Module.
If already you own a Raspberry Pi 2/3B/3B+/4/Zero, you can simply pair it with the Grove Base Hat.
Both the hardware and software configurations can be found here