DIY GPS antenna for radio

Good afternoon (evening/night optional). Today there will be a review of the GPS receiver and its application in practice.

PREFACE

In general, I always wanted to dabble with this kind of devices, I wanted to have a specific tracker that writes the distance traveled, but there was one thing, I wanted the tracker to have a display, I generally love different displays and try to screw them into everything possible , such a fetish.

There were only a few of the most extensive reviews for this GPS receiver - about 4, one of them was really good, the rest were described in general. I won't repeat myself too much.

As usual warning:

All responsibility, namely independent penetration into the body of the finished product with subsequent violation of its integrity and performance, lies with the person who committed this action.

Principle of operation

With the advent of GPS devices for determining location, fewer and fewer people know how to use a compass. The first component of a GPS navigator is its antenna. It is with the help of it that the signal is received from the nearest navigation communication satellite. The accuracy and ability to receive the desired signal depends on the correct selection of the characteristics of the receiving device (antenna).

Incorrectly selected characteristics of the receiving element can greatly complicate life during natural phenomena such as snow or rain, making location determination impossible just at the moment when it is most needed. Therefore, special design organizations are involved in the design of GPS antennas, and without mandatory field tests, the product is not put into industrial production.

Additional Information . GPS – Global Positioning System. Translated, it means global positioning system. It was originally developed by the military for their needs in North America. It has proven itself so well that military departments at the end of the last century were forced to share the technology with the civilian population.

Today, any new gadget has a built-in GPS antenna. However, the accuracy of location determination often leaves much to be desired. There are three main reasons for the device to malfunction:

The absence of a satellite at a given specific moment in a given specific area;
Poor quality of the antenna device;
Slow software.

Description of antenna operation

The GPS antenna is a component device in a wireless structure system for determining the geographic location of an object. The correct choice of the signal receiving element (antenna) ensures the ability of the entire system to operate in terms of such indicators as: signal reception range from the satellite, throughput (communication channels), and other parameters.

An antenna that is chosen incorrectly will show its negative qualities only in bad weather conditions: rain, snow, this will be reflected in the deterioration of the signal or the cessation of operation. Under normal conditions it will show good communication parameters. Designing a great antenna requires a lot of effort, no less than designing electronic products.

GPS antenna

Additional information. GPS stands for Global Positioning System, which was developed in the early 70s of the last century for the US military, but already in the mid-90s of the last century it began to be used for civilian needs. Initially there were 24 satellites in this system; as of this year there are already 31 satellites.

The purchased smartphone or tablet has a built-in GPS antenna; it communicates with the software through the driver. For this reason, experts identify three possible factors for the error in determining a geographical location:

number of GPS satellites over a specific area;
what quality of antenna is in the device;
how well the drivers work.

Antenna types

There are different types of antennas:

Built-in or external;
Active or passive.

To correctly select a GPS antenna, it is necessary to characterize the varieties listed above. This is important because Incorrect use of the part type may result in poor performance of the GPS receiver.

Active GPS antennas

This is a frequently used device with a built-in signal amplifier. The main area of application is receivers without a built-in signal receiving device, but with the ability to connect it through the appropriate connector. These devices are sensitive. They also reduce the level of interference.

Passive GPS antennas

Usually built-in. There is a very strong dependence on the external electromagnetic field. The greater its influence, the less strong the signal will reach the end device.

Manufacturers produce a huge number of different models of GPS devices, which can easily get confusing. The characteristics also differ, right down to the supply voltage. There is even a GPS antenna for a tablet on the market with filtering of spurious signals.

Today there are different configurations of models, types of connectors and brands of cables, which allows them to be used with all existing types of receivers. When choosing, you need to pay attention to the length of the cable: the longer it is, the better.

With all the variety of models, devices are constantly being modernized, improving the following indicators:

Gain;
Reduced energy consumption;
Cost reduction;
Reduced dimensions.

Appearance

The dimensions of this module are not larger than 35 x 24 mm, and it can find its place not only in wearable electronics, but also in RC devices.

The kit includes a passive antenna:

If desired, you can always replace the active one or make it yourself, using this method:

Upon request, in the comments, I will provide a link to the manual.

Today the module is not an outdated model, and is actively used, + there is support from the manufacturer's datasheet from the manufacturer's website.

And here is a page leading to the website of the manufacturer of this device

The image below briefly describes the capabilities of this family of receivers:

Connecting gadgets

Modern gadgets have a built-in GPS antenna. However, they cannot always be used as navigators. Not in all unfavorable conditions they can pick up a signal from the nearest communication satellite. Such unfavorable conditions include:

Car windows with a coating that interferes with the free passage of signals;
The size of the gadget screen does not always allow you to clearly see all the details of the route;
The overall dimensions of the tablets do not allow it to be placed under the windshield of a car.

When going to a store to purchase the necessary device, it is necessary to explain in great detail to the sales consultant the type of gadget for which the antenna is being purchased, for what purposes the device is planned to be used, as well as what result of use is required, where it will need to be installed.

All this must be taken into account because today's amplifiers use such modern means of communication as a USB port and Bluetooth. For use in gadgets, the latest encrypted data transfer protocol is preferable, because does not imply the need for additional wires that interfere with its use, for example, with a smartphone. However, with this connection it is necessary to very accurately install the antenna in the required location. Computers usually use special USB connectors.

GPS in the car

A modern car requires a navigator built into the on-board computer. Navigation is very convenient for any driver to use.

Designers involved in the design of car navigation systems settled on the following operating algorithm:

An external type device receives and amplifies the signal coming from the satellite. In an enhanced form, it ends up in the navigator;
The received signal appears in the navigation receiver. Based on this, the location of the vehicle is determined. Next, the coordinates are clarified using the system control unit;
After specifying the coordinates of the vehicle's location, the optimal route to the final destination is calculated. This happens on the basis of road maps loaded during the production of the machine. The navigation system is often controlled by voice. If it is necessary to update maps loaded into the car’s memory, use special boot DVDs;
The correct direction of movement is determined using the parameters of the angular velocity of the wheels, which is calculated by the on-board computer.

How to connect a GPS antenna to a tablet

Modern mobile devices and tablets have an internal GPS antenna, but they cannot be equated to a navigator, since these devices cannot always pick up a signal from a satellite when reception conditions are poor, namely:

Coated car windows that do not allow full signal transmission;
The overall dimensions of the tablet do not allow it to be placed under glass;
A small review.

A simple way out of this situation is to make a connection; A GPS antenna for a tablet will become almost 100% a navigator. You can do this work yourself or contact the service.

Important!
The external antenna is presented in miniature form, it is placed in a special box, which has dimensions no more than ½ a box of matches, a special cable comes out of it, shielded along the entire length, which can be different, it depends on the modification of the antenna, generally about 3500 millimeters are installed . The antenna unit is connected to the tablet through a special connector; this type of antenna can be connected to a desktop PC or smartphone.

DIY GPS antenna

There are situations in which, without determining the location, you can find yourself in a very unenviable position. In this case, navigation devices are simply vital. Here, a weak signal from a communication satellite or its complete absence is unacceptable. Then, knowing what a GPS antenna is, you have the opportunity to make it yourself.

The figure below shows how you can make the necessary element from scrap materials:

Take a wire, preferably copper, of small cross-section. In our case, 2.5 mm²;
A square of the appropriate size is bent from the wire. The dimensions of the sides are shown in the figure;
We attach the resulting part using soldering or electrical tape (adhesive tape) to the GPS receiver.

As a result of the manipulations performed, a signal acceptable for determining the location coordinates can be obtained.

GPS antennas are indispensable in modern GPS receivers for determining location on the ground. They are very much in demand by tourists who use these devices to correctly plot routes.

Antenna overview

Below are descriptions of several well-known models of GPS antennas.

GSM whip antenna

Simple antenna

A simple antenna with the following features:

The approximate cost of such a magnetic-based antenna is only 250 rubles;
This antenna is equipped with an SMA connector;
The cable that comes with the antenna is 2.5 m long.

GPS/Glonass antenna SMA

With SMA connector

The antenna with SMA connector has the following features:

The antenna gain is 27 dB;
Dimensions 15x50x40 mm;
Cable 3 meters RG174;
Power supply with voltage 3-5 V;
Purpose: car navigators or car radios with GPS modules.

GPS/Glonass antenna Fakir

GPS module and antenna

Antenna with angled car connector, more convenient for connection. Differs in the following characteristics:

Gain is 27 dB;
Antenna dimensions – 15/50/40 mm;
Connector – Fakira GPS;
Cable 3 meters RG174;
Purpose – car navigators or standard head units with a standard Fakir jack connector.

Types and principles of operation of antennas

Antennas pick up electromagnetic waves that travel everywhere. A weak electromotive force of alternating radio frequency current is induced in the antenna conductor. It is sent to the receiving device. After this, amplification, detection and selection of the required information occurs.

Antennas are divided into active and passive. The first ones are distinguished by the presence of an amplifier that increases the signal from the car antenna. Active receiving devices provide stable reception of radio stations at a distance of more than 60 km from the transmitter.

Passive antennas do not have an amplifier. They are easier to assemble with your own hands. A passive car antenna is most often installed on the roof of a vehicle and provides reliable signal reception at a distance of up to 15 km, for example, within city limits.

Are you a car driver?! Then you can take this simple test and find out. Go to test »

Antenna installation features

Many car alarms feature two-way communication. To enhance signal capture they must use appropriate GPS. Many car owners are often faced with the fact that their car alarms pick up signals very poorly. In most cases, this is explained by the fact that before installing the equipment, the specialist did not read the instructions. That is why the transceiver module is installed on a silk-screen printing, which is placed on the windshield.

In most cases, the antenna is installed in this way for the reason that it is practically invisible from the outside. But installers should be aware that silk-screen printing uses a special paint that contains a huge amount of iron. If you glue the antenna to it, the quality of the equipment will deteriorate significantly. Many repairmen have noticed that as soon as the device is removed from the silk-screen printing, it begins to work correctly and accurately. That is why experts recommend installing the equipment on a clean area of the windshield. Also, the GPS device can be installed under plastic torpedoes.

Assembly instructions

You can make an antenna for a car radio with your own hands at home from materials and tools that are available in your garage or workshop. Rigid steel or aluminum wire is suitable for the pin. The housing can be made of wood or plastic that does not interfere with the reception of radio waves.

To attach a homemade antenna for a radio with your own hands on the roof of a car, you will need a magnet from a faulty speaker. A cut-to-shape piece of plastic film or lint-free cloth is glued to the side that will be in contact with the car body to protect the paintwork from damage.

Inactive

To make a car antenna with your own hands, you will need:

hard copper or steel wire;
M5 screw with nut and locknut;
hot glue or heat shrink tube;
RF cable with plug for car radio;
primer, epoxy resin or thermoplastic;
screwdriver, wire cutters and file.

To make a pin, unwind the wire and cut a piece from 20 to 50 cm long. Then it should be straightened, and the lower end should be bent at a right angle and rolled into a ring to put a bolt on the pin, with which the radio cable will be connected. The lower part of the vibrator can be twisted into a spiral.

After this, the body is prepared. A hole is made at its bottom for a mounting magnet, which is attached with glue. The central core of the radio cable is connected to the pin via a bolt. The screen braid is moved back and insulated so that it does not short-circuit to the vibrator. Otherwise, the radio in the car will not work.

The next step is to install the FM antenna for the car into the housing. To do this, make a hole in it in the shape of a bolt, which is then inserted and fixed by pouring cold welding, other hardening resin or plastic. This part should be shaped into a cone and sanded after curing for a neater appearance.

You can also make a car radio antenna with your own hands at home in the form of a shark fin. To do this, you will need an anchor bolt with a length of 10 to 25 cm, in both ends of which holes must be drilled. Flexible copper wire should be wound on it in 2 layers as tightly as possible. Its ends must be inserted into the previously drilled holes. The upper end should be securely soldered, and a nut with a lock nut should be screwed onto the lower end.

Then the outer layer of insulation should be made from epoxy resin or thermoplastic and shaped into the desired shape.

Vinyl or carbon fiber should not be used as they interfere with radio reception.

When the body has hardened, the surface should be processed on a lathe or by hand sanding to give the product a neat appearance.

We install the radio in the car with our own hands

What you need

First, you should carefully examine the hole for the car radio. Inspect the mounting grooves, find out the presence of a standard ISO connector or its absence. Then you need to select the type of radio to be installed. Conventionally, all devices are divided into two groups:

Built-in type. Such models are equipped with a removable panel to prevent theft. Although there are older devices where the front panel cannot be removed. The choice here is almost unlimited. From simple and cheap radios to expensive “heads” with a retractable mini-screen for navigation and DVD viewing.

Stationary type. They are made by the manufacturer specifically for a specific car model. It is worth clarifying that some car models, especially before the 2000s, could be produced without radios in basic versions. They were installed in more expensive trim levels. It is from these cars that you can get a radio in good condition if your car does not have one or it is broken.

Now let's prepare the remaining tools and materials:

sharp knife (pliers);
electrical tape and a screwdriver (not always needed);
wires to the speakers (in some cars they are laid initially, even in the absence of a standard head unit);
multimeter (needed only if there is no standard connector).

Next, read the instructions for the receiver. It contains a complete list of connection recommendations. Having received maximum introductory information, you can proceed to installing the radio in the car.

We connect the radio in different ways

Connecting the radio with an ISO chip

Modern cars are connected to the radio using a standardized ISO connector. You just need to snap the chip into the device socket. It's easy and quick - even a girl can do it. This is how you connect the stereo system, power and a standard antenna.

Installing an active antenna

You can install an active antenna in your car yourself. You will need it if the main antenna is broken or its signal is not strong enough. The purchased antenna is mounted in a free area of the windshield, then the power wire (red, less often blue) is connected to the ISO. The zero wire (black cable) is attached to the car body, closer to the antenna.

How to properly install a car antenna

When you complete this operation, all that remains is to insert the signal wire. Usually at its end there is a DIN type connector. This is an old connector that can be found on Soviet TVs. Audio system manufacturers are refusing to use such a bulky plug. Therefore, companies design their own antenna connectors. You can connect a standard DIN plug to this socket using an adapter. It can be found in a radio parts store or car market.

Wired connection

It is assumed that the car does not have an ISO connector installed. Such options are found on old foreign cars and most domestic cars. To connect, you need to purchase an additional ISO connector yourself. It is sold in almost any car store (or comes complete with a car radio).

The wires to the chip are wired according to the color scheme. They are standardized and signed

But you should exercise some caution. It is better to check the user manual again, because

Different manufacturers may designate outputs differently. You can test the wires coming out of the car with a multimeter to know for sure what goes where.

Connecting the power supply to the radio

The device is connected to the car's power supply via an ISO chip. In this case, the wires from the battery are inserted into the corresponding connectors on the connector. There are several types of power switching: directly to the battery or through the ignition switch.

These methods will be discussed in more detail below, where we will look at the full ISO color layout.

Detailed description of ISO

Power supply bypassing the ignition switch

It is possible to connect the ACC and +12 V power wires. In this case, the radio will work constantly. For example, when parking a car with the engine turned off, you can listen to music. This method is not recommended for car radios with high current consumption.

Additional connectors

Are there any nuances?

It happens that manufacturers can make it difficult to install a radio in a car. These, for example, include the Pioneer company. Often there is a disturbed color order in which the head unit is connected.

To do it correctly and for sure, you should carefully study the instructions for connecting the receiver and only then proceed with installation.

Advantages and disadvantages of homemade devices

One of the advantages of a homemade car antenna is the ability to more accurately adjust to reception conditions by choosing the length of the receiving pin and the installation location on or inside the vehicle body. With careful and correct assembly, the sensitivity and bandwidth of a homemade receiving device will be no worse than that of a factory one.

One of the disadvantages of homemade antennas is the need to drill into the car body. Over time, the hole may rust. Some homemade antennas may not comply in their dimensions with the Road Traffic Regulations.

Connection and setup

Before connecting a homemade antenna for a car radio, you need to make sure that the cable is not damaged. It is then routed under the car's dashboard to the radio. If the cable is inserted into the cabin through a hole in the roof, then all holes are carefully sealed. The cable plug is inserted into the car receiver.

If the receiving device is assembled correctly, then all available stations should be received clearly and reliably without on-air debris. The power wire of the active antenna is connected to the blue and white stripe wire of the car radio or directly to the battery via a switch.

The GPS antenna is used to determine with special devices the coordinates of the area in which a person is located at a given specific moment. Recently, our country has its own development in this area - the GLONASS system. Modern GPS receivers, without additional clarification systems, have sufficient accuracy to determine location - in the region of 3 meters.

Bottom line

In general, the logger works, you can write a track, followed by editing on the map.
Also in software from Google, the track can be saved in a more popular format that other maps support. I more than satisfied my curiosity.

The downside is that it is a small antenna; sometimes a cold start can take up to 10 minutes (depending on how cloudy it is and the time of day). The antenna, of course, can be replaced with a homemade one, or purchased in addition; there are quite a few active antennas on the market.

Thanks for your time.

Principle of operation

Antenna types

There are different types of antennas:

Built-in or external;
Active or passive.

Active GPS antennas

Passive GPS antennas

Usually built-in. There is a very strong dependence on the external electromagnetic field. The greater its influence, the less strong the signal will reach the end device.

With all the variety of models, devices are constantly being modernized, improving the following indicators:

Gain;
Reduced energy consumption;
Cost reduction;
Reduced dimensions.

Antenna classification

GPS antennas are classified as: active or passive, built-in or external. Experts focus on the fact that the antenna plays an important role in this system. Even a powerful device, but with an incorrectly selected antenna, can show parameters much lower than the passport data.

Active GPS antennas are a standard antenna with a signal amplifier built into the circuit. They are often used in receivers where there are no internal devices, but there is a terminal for connecting an external antenna. The active elements of the system are more sensitive, namely the signal level to the surrounding noise is higher, in addition, there is a decrease in interference.

A passive GPS antenna is characterized by the surrounding electromagnetic radiation: the higher it is, the weaker the signal will reach the receiver. It is recommended to install active antennas in the car, with a larger amplitude; the choice depends on the installed receiver and the presence of an antenna amplifier.

Manufacturers of GPS antennas offer customers a large selection of internal and external models of these devices; there are differences in supply voltage, from 3 volts to 5 volts; in addition, the devices also have additional bandpass filters for removing a signal (cutting) that is outside the desired range.

The car GPS antenna for the navigation unit has a frequency range of 1575.42 plus or minus 3 MHz. Taking into account the operation of the bandpass filter, this results in 10 MHz, with a gain of 4 Decibels and a power dissipation of one watt. These devices show stable operation under the following temperature fluctuations: minus 40 degrees – plus 100 degrees Celsius, humidity is considered 100%.

In addition to a large selection of antennas, manufacturers offer different configurations for them according to cable brands and types of connectors, which makes it possible to use them with different types of devices. An important indicator in the configuration of the cable is its length; now it reaches five meters. Optimization of antennas is carried out according to various indicators, these are: gain, reduction in energy consumption, reduction in the cost of devices, reduction in the overall dimensions of devices.

Connecting gadgets

Car windows with a coating that interferes with the free passage of signals;
The size of the gadget screen does not always allow you to clearly see all the details of the route;
The overall dimensions of the tablets do not allow it to be placed under the windshield of a car.

GPS in the car

A modern car requires a navigator built into the on-board computer. Navigation is very convenient for any driver to use.

Designers involved in the design of car navigation systems settled on the following operating algorithm:

An external type device receives and amplifies the signal coming from the satellite. In an enhanced form, it ends up in the navigator;
The received signal appears in the navigation receiver. Based on this, the location of the vehicle is determined. Next, the coordinates are clarified using the system control unit;
After specifying the coordinates of the vehicle's location, the optimal route to the final destination is calculated. This happens on the basis of road maps loaded during the production of the machine. The navigation system is often controlled by voice. If it is necessary to update maps loaded into the car’s memory, use special boot DVDs;
The correct direction of movement is determined using the parameters of the angular velocity of the wheels, which is calculated by the on-board computer.

When setting up a vehicle location on a map loaded into its memory, the vehicle must be at static rest and in the location indicated on the map. In this case, the GPS antenna for the navigation unit is installed at the factory.

How GPS works in a car

To simplify the understanding of the operation of the car positioning system, specialists have made a simple algorithm of concepts that represents the following:

An external GPS antenna receives and amplifies the signal received from satellites, transmits it to the navigator receiver;
The navigation unit contains a signal receiver that calculates the location of the car based on the signal received from the GPS antenna, then to clarify the position, the parameters are transmitted to the navigation system control unit;
The task of the navigation block is the final calculation of your location; it should show the route to the point of destination. The block adjusts the loaded road map and calculates the distance to the selected destination. The navigation unit controls voice commands, the DVD device, and shows the desired map fragment on the display;
The direction of movement in the navigation unit is calculated based on data obtained from the angular speed of the wheel and the VSP signal parameter of the car, which comes from the ECM of the computer.

To correctly determine the position of the car, you need to set up a road map, which marks the location of the car. The road map is transmitted through the DVD device to the navigation unit and compared with the position of the car. You cannot configure the map when the car is in motion, or when the car is on a road not marked on the map.

DIY GPS antenna

The figure below shows how you can make the necessary element from scrap materials:

Take a wire, preferably copper, of small cross-section. In our case, 2.5 mm²;
A square of the appropriate size is bent from the wire. The dimensions of the sides are shown in the figure;
We attach the resulting part using soldering or electrical tape (adhesive tape) to the GPS receiver.

As a result of the manipulations performed, a signal acceptable for determining the location coordinates can be obtained.

GPS antennas are indispensable in modern GPS receivers for determining location on the ground. They are very much in demand by tourists who use these devices to correctly plot routes.