A friend asked me to find him a tablet with GPS for driving through forests and cities, so as not to get lost and that it also had Bluetooth to connect an external GPS receiver. The choice fell on one with an external GPS antenna, a resistive 10" screen, a normal hole under USB devices and even with an Ethernet interface. (ATTENTION this is a repost from Habr)
Characteristics
CPU: 1GHz CORTEX A9GPU: Mali 400
RAM: 512MB or 1024MB (depending on the age of the model)
ROM: 8GB (of which 6 GB are available to the user in the form of a nand flash drive and about 1GB more for programs), versions with 4GB and 16GB are also available
Screen: 10.2" 1024x600 resistive multi-touch (in fact, it just understands gestures in software, like pinch to zoom)
Connection: WiFi b/g/n, Ethernet and 3G modems via USB-host
GPS: built-in, but external antenna on a long wire
Interfaces: USB-Host, USB-OTG, RJ-45, HDMI, 3.5mm audio, microSD memory card slot
Multimedia: built-in stereo speakers, front 0.3 megapixel camera for Skype
Battery: I couldn’t find out, but it seems that depending on the model/seller it ranges from 3Ah to 7Ah and judging by the weight, I didn’t get a model with 7Ah
Dimensions: 270 x 170 x 16 mm
Weight: 700 grams (it seemed less to me)
The official website of the manufacturer, there are also new firmware versions and, judging by the dates, support for the tablet has not been abandoned, as is usually the case, but has been discontinued (according to the manager of the buysku.com store), but it looks like this is its clone or twin.
Appearance and interfaces
When the box with the tablet arrived, I was a little surprised by the size, after all, 10" is too much. On the front panel there is a screen, a back button and a 0.3Mpx camera peephole.
On the right side are all the interface connectors: DC-in, Ethernet (probably useful for someone, I just tried it - it works great), HDMI, USB-OTG, microSD, USB-host (very tight, if a device gets in there, you can’t accidentally pull it out will work), 3.5mm headphone jack.
On top of the device: an incomprehensible switch (I thought it was hold, but it doesn’t block anything), speakers (left and right), lock button, menu, volume rocker, power button, microphone, connector for an external GPS antenna and a stylus (I was nostalgic, really useful and handy thing).
Nothing interesting was found on other sides.
Accessories: external GPS antenna (for which everything was started), a charger with a USB cable and an adapter for a European socket, as well as instructions for using version 4 of Android.
Performance testing
Here I apologize in advance, I didn’t have much time to test the tablet properly and take beautiful photos, and I also didn’t notice that you can take normal screenshots, and not “screenshots”.
Electopia
AnTuTu
Quadrant
As you can see, the performance is not bad at all and most games work, but the controls are not so great, since most are designed for multi-touch. 
Browser, Skype and other information
But surfing the Internet is a real pleasure - sites look the same as they do on a large computer.
Skype supports video calls, but the picture slows down noticeably (5-10fps to the eye) and the camera of the tablet itself looks higher than it should, as a result the interlocutor sees the top of my head.
Example of a photo from a camera
Multitouch is implemented in software, since the screen technology does not allow us to normally determine the number and coordinates of clicks. Therefore, only one touch fully works. I thought that with such a large screen size there would be a lot of false positives, and in general it would work poorly, but it turned out to be completely wrong - any poke on the screen works very accurately, and with the stylus you can even write calligraphically.
System information: 
GPS
It's time to talk about GPS; in fact, this is the only reason I bought the tablet for a friend. The rest of the story is from him, but sometimes I’ll chime in.Based on the seller’s description, you can’t clearly understand what the built-in GPS module is, so testing comes down to a comparative analysis with the external wireless GPS module Holux M1000.
Testing within the apartment.
The module built into the tablet performed well and, with the antenna hung on the window, easily caught up to 10 satellites and was quite stable.
Lyrical digression: the tablet was initially purchased only to be used as a navigator with an external module connected via Bluetooth. The manufacturer stated that the VT will be built-in (actually I stated this, the seller wrote strange support, which meant possible support, as with 3G modems, but I hoped that support=built-in), but upon receipt of the parcel a USB-BT-dongle was detected (which I took out from the bins of my homeland, there was nothing in the kit), which is inserted into USB and accordingly sticks out, causing a lot of inconvenience.
Let's get back to our testing. We connect an external GPS Holux M1000 via BT, there were no problems with this, the tablet happily paired with it without a single delay.
Holux also caught 10-11 satellites, but with a more stable signal than the built-in module. Although the difference is not particularly noticeable.
Testing in city navigation conditions.
During this test, there was a big disagreement between the built-in module and the external one. The built-in one caught 5-6 satellites, compared to 11-12 for Holux"a.
Testing in nature, far outside the city.
Outside the city, in the open air, both navigators showed approximately the same results as in the city, with only a slight difference: the receiver built into the tablet sometimes lost the signal. Actually, there wasn’t much opportunity to take photographs; I’ll attach just a couple of photos from the last testing site.
Impression.
The GPS module built into the tablet should be used only if you are within the city; it receives satellites stably and works well with navigation programs such as 
All modern tablets and smartphones have built-in GPS, but they cannot be compared with full-fledged navigators. Gadgets cannot always pick up satellites in difficult reception conditions. This happens under different conditions:
- The windows in the car are covered with a special coating, which impairs signal reception.
- The tablet cannot be placed under the windshield.
- Limited visibility – this applies to special equipment.
But there is a simple way to bring your tablet as close as possible to a full-fledged navigator - install an external GPS antenna. Some motorists turn to service centers, but why pay if you can do the work yourself.
Reference! The external antenna is housed in a compact box, the size of which usually does not exceed half matchbox. A shielded cable comes out of the box; its length depends on the model, but usually the cable is 3-3.5 meters. A special connector located at the end of the cable is connected to the signal receivers, in our case, to the tablet. The antenna can also be connected to a smartphone or computer.
Installation process
When choosing an antenna, you need to explain to the seller what device the GPS signal amplifier will be used for. Modern models can be connected not only via USB, but also via Bluetooth. And now to the connection:
- The ideal solution for your smartphone would be a GPS antenna that connects to the device via Bluetooth. All data will be transmitted via the protocol. The advantage is that you won't need any additional connectors or modification.
- Due to the fact that the tablet already has a navigation application, you do not have to make new settings.
- Also, an external receiver may have a USB/PS2 connector. This interface is usually used personal computers, laptops, but there are exceptions. As in the first case, you only need to connect the antenna to the device.
It is rare, but there are tablet models that do not have a USB input. In this case, it is worth purchasing an external Bluetooth GPS antenna. The increased efficiency of such an antenna can be explained by the presence of an autonomous power source. It is also important to secure it correctly. Some motorists take it to the roof, others attach the modifier under the glass. In any case, with an external GPS antenna, your tablet will work no worse than a separate navigator for a car.
The GPS module in your phone allows you to use navigation applications such as Google Maps, and location services. And a good signal is crucial not only for navigation, but also for augmented reality games like Pokemon Go. If you are experiencing problems with this on your Android phone, then check out our tips to help improve the GPS signal on your Android device.
What is GPS?
To know how to optimize the performance of the GPS module, you need to understand how it works. GPS stands for Global Positioning System, that is, a global positioning system. It was developed by the military, but later began to be used for civilian purposes. GPS originally used 24 satellites orbiting planet Earth, but the number has now increased to 31.Your smartphone communicates with these satellites through a special antenna that is part of hardware in most modern mobile devices. Naturally, the hardware is controlled by software through the driver. Thus, there are three sources of error for the GPS signal in a smartphone:
- Number of available satellites at current location
- The quality of the antenna that is inside the smartphone
- Driver implementation in operating system Android
Switch to High Precision mode
For getting better signal, you should prepare for the fact that your device's battery life will be lower than usual. It's a necessary sacrifice, but you can still change the settings back when you don't need to pinpoint your location. For example, when you play Pokemon Go. It's very simple, follow our instructions in the instructions below.Open Settings, go to Location and make sure location services are turned on. If they are turned off, then click on the switch on the right top corner.
At the very top, under this switch, there is a menu with mode selection. Tap on it and make sure that the “High accuracy” option is selected. This means that the built-in GPS, Wi-Fi and mobile network. This may increase power consumption, but the detection accuracy will improve significantly.
Make GPS always active
To save battery power, the GPS module can be turned off when not in use. If, for example, you are playing Pokemon GO and at that moment you want to read a new message, then the GPS will turn off for this time.One way or another, you can force it to always be active, but this is not difficult to do. You need to install one application from Google Play Store, and it will do everything for you. We recommend Connected GPS because it's the easiest to use. Keep in mind that this can be a real blow to the autonomy of your device.
Why might GPS not work?
With GPS Essentials, you can diagnose the cause of a weak GPS signal. Problems may arise from hardware or software. On the main screen of GPS Essentials, find the “Satellites” item and go to it. The smartphone must connect to satellites available in Earth orbit.If your phone has not found any satellites or is unable to connect to them due to a poor signal, then the reason for this may be interference from metal objects around you: the smartphone case or the module built into it simply does not work as it should. If the satellites appear, but the GPS is still not working properly, then the problem is in the software and we recommend using the next tip on the list.
Clear GPS data
Sometimes your device gets stuck on some GPS satellites, even if they are not within range, which causes problems in the module's operation. This can be corrected using another application - GPS Status & Toolbox, which clears GPS data and the phone can reconnect to satellites from scratch.Install this tool and then run it. Press the “Menu” button, where you need to select “Manage A-GPS state”. Next, you need to click the “Clear” button, and after completing this process, return to “Manage A-GPS state” and click on the “Download” button. That's it, after this the GPS module should work like new.
Buy an external GPS receiver
If the GPS on your smartphone still does not want to work or its accuracy is not enough for you, then you can try an external GPS receiver. It can be synchronized with your phone via Bluetooth and charged with the same charger, which comes with the smartphone. The only problem in this case is the cost of an external GPS receiver, since good model you will have to pay about 6,000 rubles.Modern smartphones are equipped with a GPS chip, which greatly simplifies our travels or searches for a specific address. However, there are often cases when GPS does not work well. And it's not always enough to blame good build smartphone. You can often improve the functioning of the navigation module by tinkering with the settings.
Many motorists have a full-fledged GPS navigator. Some of these devices have back wall or the side end there is a connector for the antenna. This allows you to enhance signal reception several times - you just need to get the appropriate antenna.
As for modern smartphones, we hasten to disappoint you. You will never find a special antenna connector in their composition. The only way to improve GPS reception on Android is using software methods. If they don't work, then you will have to come to terms with the current state of affairs. As you might guess, GPS satellites work the worst budget devices. This is explained by the fact that they are equipped with the cheapest and oldest navigation chips, which have a low operating speed and a weak signal receiver.
Visiting the settings section
In many smartphones and tablets, the GPS chip is completely disabled by default. In this case, the device determines the location by cell towers and Wi-Fi networks. To enable the navigation chip, you need to configure the device. To do this, do the following:
Step 1. Go to the section " Settings».
Step 2. Here you should be interested in the item “ Location».
Step 3. On different devices This item may have a different name. For example, on Samsung tablets you need to select the “ Connections" and click on the item " Geodata", at the same time activating the corresponding switch.
Step 4. In this section, you need to enable high location accuracy. The device must use all sources for this - GPS satellites, Wi-Fi networks and data from cell towers.
It should be noted that in this operating mode, energy consumption increases. And if this is practically not noticeable on new smartphones, then owners of budget and older devices will definitely feel the reduced battery life.
Compass calibration
If it is impossible to enhance the signal reception on smartphones, then no one can stop you from improving the performance of the digital compass. The fact is that on some devices it is not calibrated, as a result navigation program cannot understand in time which direction of the world your smartphone is facing. At this moment it seems to you that the device does not pick up GPS.
To calibrate the compass you will need an app GPS Essentials. Download and install it, then do the following:
Step 1. Launch the program.
Step 2. Enter the mode Compass.
Step 3. If the compass works stably, then the problem is not with it. If the compass refuses to show the cardinal directions correctly, then calibrate it.
Step 4. First, rotate the smartphone around its axis with the screen facing up. Next, turn it over from bottom to top. Well, then turn it over from left to right. This should help. In some versions of the application, you must first select Calibrate in the section settings.
Viewing the number of visible GPS satellites
In the same GPS Essentials you can look at how many satellites your smartphone connects to. If it is large enough, then the navigation chip should not be blamed - the problem is in one of the programs. To view satellites, you need to select the item in the application menu Satellites.
Resetting GPS data
A common problem with some devices is that they take a long time to lock onto specific GPS satellites, even when they have managed to move out of sight. The application can help in this case GPS Status & Toolbox. It will reset the GPS data, after which the connection to satellites will be made from scratch.
Step 1. Download and install the utility.
Step 2. Run installed application, agreeing to the terms of the license agreement.
Step 3. On the main screen of the program you will see readings from various sensors, as well as information about the number of GPS satellites overhead.
Step 4. Click anywhere on the display, after which you can pull out the curtain with the main menu on the left. Here you can calibrate the compass if this was not possible using the application discussed earlier. But now you need to click on the item “ A-GPS state management».
Step 5. In the pop-up menu, click the button " Reset».
Step 6. After the reset is complete, return to this pop-up menu by clicking the " Download».
What to look for when buying a new smartphone?
Now you know the answer to the question “How to set up GPS on Android?” But all this will not help you very much if you want to use your smartphone as a GPS navigator on permanent basis. It’s better to get a good quality one for these purposes. modern smartphone. When choosing it, be sure to read the full technical characteristics. In them you need to find a mention of support for A-GPS technology - it greatly reduces energy consumption. The ideal smartphone for you will be one that also works with GLONASS satellites. Fortunately, with the support of the Russian navigation system Almost all devices that have been imported into our country over the past year have it. But, again, you still need to look at the specifications of the device before purchasing it.
An external GPS antenna allows the GPS receiver to determine the geographical position in specific moment time. On the territory of the Russian Federation, the GLONASS navigation system is widely used, the accuracy of a person’s location with a GPS receiver reaches 3 meters, for older commercial models the position accuracy is about 150 meters in conditions of a poor signal from the satellite, in open areas - about 3 meters. Exist additional systems corrections (SBAS), applying which the accuracy is determined by one or two meters.
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 such indicators as: range of signal reception from the satellite, throughput(communication channels), 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.
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 ( software). 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 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 powerful device, but with an incorrectly selected antenna it 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. Recommended for installation in a car active antennas, 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 devices. An important indicator The cable included in the package includes 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.
How to connect a GPS antenna to a tablet
Modern mobile devices and tablets have 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.
How to connect an external antenna to your device
By purchasing outdoor antenna gps, you must clearly explain to the seller what device you are taking it for, this must be done, since modern signal amplifiers can be used using USB port, as well as Bluetooth, namely, connect it yourself:
- A signal amplifier with a Bluetooth connection is ideal for a smartphone; all parameters will be transmitted using a special protocol, you do not need additional connectors;
- PCs and laptops now have a USB/PS2 connector installed, so you can choose an external amplifier to connect through it;
- Not on some tablets USB input, then the solution would be to connect via Bluetoot; the effectiveness of this antenna is achieved by an autonomous power supply and the need to correctly install the antenna mount.
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 travel. 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. Roadmap through DVD device broadcast in navigation block and is 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.
How to make an outdoor amplifier yourself
Knowing your own location is important in some cases, so navigation is increasingly becoming part of daily life. Very often, users are faced with a weak GPS signal when it is needed, or even its complete absence. A way out of this situation could be a self-made antenna for any device with a GPS module.
A device of Chinese origin with a GPS module often suffers from a lack of signal; The reason is a weak signal receiving module. The antenna is operated by a patch located on the outside of the device. It should be noted that this device works outdoors, but the signal disappears if poor reception conditions are created (bring the device into the house, put it in the car). Procedure:
- We determine how difficult or easy it is to get to the GPS module;
- We take copper wire with a cross section of 5/2 millimeters square, a length of 46 millimeters * 4, where 4 are the sides of the square, it represents a square;
- We make a regular square from the wire, use pliers, we need to keep the dimensions exactly, how the antenna will work depends on this;
- Solder the antenna to the external GPS patch.
For convenience, the antenna can be attached to the device body with tape. The result of the work performed is stable signal reception by the device indoors and in the car.
Example homemade antenna GPS makes it possible to receive a signal even in bad weather conditions and inside the car. Travel enthusiasts often use navigation when they need to plot a short route from one point to another. An outdoor GPS antenna guarantees stable signal reception.
Video