[GPS Technology] The main key technology of GPS chip is the three generations of GPS chips 9 major knowledge

With the development of science and technology, the development of GPS navigation is increasingly worth looking forward to, and the development of the core technology of GPS chip is the most worthy of our concern.In the process of the development of GPS chips, "miniaturization" has always been an important development direction, which has led the GPS chipset to reduce power consumption and reduce volume.The system can provide detailed and accurate positioning information and traffic information, which can easily achieve the CPS satellite navigation function.

In recent years, due to the increase in chip manufacturers and providing integrity solutions, module manufacturers are more likely to develop integrated products. Therefore, a large number of manufacturers have invested in the production of receiver products.The effect of helping the GPS boom has also caused the price of GPS chips with the highest cost of GPS machine costs, and the GPS chip used to provide consumer electronics products has also begun to show their figures. In addition, chip manufacturers have gradually improved their performance performanceTherefore, the chip positioning ability has gradually closer.Under this trend, how GPS chip products win the affirmation of buyers, and have become the key factor in competing with each GPS chip in the market.

Speaking of the main key technologies of GPS chips, this includes responsible signal processing -base frequency (Baseband) and receiving signal -RF (RF).Since the GPS signal frequency (1575.42MHz) comes from a high altitude of 20,000 kilometers from the ground, the signal is very unstable, so the antenna receiving signal has been enlarged, filtered noise, frequency reduction, and sampling (RFFRORONT END) after the antenna receiving signal, and then passes throughAfter RF, the signal enters the base frequency processing section, and the digital signal sampled in the previous paragraph is calculated and output to facilitate the use of user interfaces. Among them, the GPS Baseband DSP chip is the core component, which is responsible for processing the address signal.

Based on the above, the two parts of RF and the base frequency include micro -processor Microprocessar, low noise amplifier (LNA), digital ections, RF Section, antenna Ele -Ment.), Output into several important components of the drive (GPI andDrivers) and the PRO -CESSOR PERIPHERALS.The integration of various GPS chip solutions on the market makes the GPS chip market is facing great variables.The first is "miniaturization". Looking back at the development history of GPS chips in recent years, with the combination of GPS and other products, and emphasizing that the volume of the terminal product is light and short, the GPS chip direction of the system single chipization of the system is an inevitable trend.At present, manufacturers can divide radio frequency or base frequency single chips for GPS single -chipization, and integrate more functionality.In the RF chip part, many manufacturers have integrated amplifier, filter, frequency reduction, frequency synthesizer and oscillator;Flash), power management time clock, etc.

Therefore, we see that the size of the GPS chip has gradually narrowed, and the GPS chip has developed from a dual module to a single module. In the future, GPS equipment products will become more and more vigorous, and chip demand will become greater.In addition, GPS chips will also face customer -based demand. In the past, most GPS chips were in the automotive market.At present, GPS chip applications have begun to be used in mobile phones and PDAs, or special personal carrying devices, such as the tracker for the elderly and children.The GPS chip may also be integrated with other functions, such as Bluetooth, USB, etc.Therefore, more and more customized modules designed for special applications will also be increasing.At present, most of the global investment in GPS chip development is mostly with foreign manufacturers, such as Sirf, Ti, XEMICS, FreeScalc, STM and other large manufacturers have launched GPS chips. Among them, Sirf is the world's largest GPS chip manufacturer. The product line is quite complete and can provide a full range of series.Solution product.

GPSKnowledge descriptionGPS"Three -generation chip" knowledge

Recently, in GPS products, the so -called "three -generation chips" are often mentioned.However, neither merchants and users have clearly explained and understand, and even misleading and misunderstanding.Exchange your own experience and views with you.

1. GPS chip: There are currently three main chips on the international (common/more popular) GPS module (common/more popular) GPS module (common/more popular) GPS module (OEM board).

(1) American SIRF (SIRF)

(2) Sony (Sony Ericsson/Sony Ericsson) chip

(3) Swiss Nenem NEMERIX chip

2. The core of the third -generation chip:

The chip hardware is similar, but internal software plays a main role.The so -called core technology of the three generations is only to improve the software algorithm on the basis of the 2nd generation. It is like the formula for calculating the acceleration/speed in the primary and high school physics classes, but in the university's higher mathematics, the number of guides and points in the university to calculate the same acceleration/The physical problems (algorithms) of speed are different. The time used is very different. It reflects the difference between middle school and university, just like the 2nd and 3rd generations.The second is that the hardware also provides quality standards.

3. The main function of the three -generation chip software:

3 generations of chip software improvement upgrade: (1) Algorithm improvement improves the stars/positioning speed time.(2) Improve anti -interference performance, signal -to -noise ratio, and receive effective star numbers through software filters.(3) Some chip implementation software DR trace (rotation) calculation, improving anti -high -rise buildings, shade, underpass cover and tunnel function.(4) soft channel search, search to increase the number of channels for visual satellites (12-24), and can continue to position when personnel, vehicles, uphill, and posture changes, airplanes, and Ship star calendars changes.

4. Three -generation chip hardware improvement:

(1) The power consumption of the chip is reduced and the volume is reduced (compared with the 2nd generation).

(2) Improve anti -interference capacity, full shielding or dual chip separation.

5. GPS module and product:

gpsgpsEven wires, connectors, etc. look irrelevant components).

6, antenna is an important factor:

GPS antennas must be used in common GPS products such as handheld, PDA, Bluetooth, G-MOUSE, etc., regardless of active, passive, or even omniscient antenna, more than a dozen performance indicators, angle (except for 1600 maximum full antenna), DB of amplifiers, impedance range, material, anti-interference ability and module matching determine the performance of the entire product, and even 2-3 antennas (above and bottom) on the aircraft.position.In other words, the 3 -generation module is very good, and the antenna may not match the 2nd generation products.

7, number of channels:

Three stars are two-dimensional, 4 stars are three-dimensional positioning. This is the basic principle of GPS. We use 11-12 pieces on the ground (because the antenna is 160 degrees angle).) You can collect a few more (must be omnidirectional or more or more antennas), but it also takes 3-4 of the 3-4 signal and the nearest effective satellite for calculation positioning.Four channel positioning, a channel quickly search for all visual satellites, and compared with 4 of the effective stars, it is replaced by one of them, so that 4 strongest signal satellites are maintained.Therefore, the higher the passage, the better, the generally 12 are enough. What 16, 18, 20, 24 ... are soft channels, which reflect the number of visible satellites that can be searched for viewing satellites. It has no practical significance.

8. Induction (DB number):

The degree of induction of GPS receiving signal (-150-195DB) The standards of each manufacturer are not uniform, some are modules, some are modules contain antenna, some are the average, some are peaks (maximum value).Everyone's actual environment (electric field, magnetic field, high-voltage, microwave, geomagnetic ...) is very different. Therefore, the difference between this indicator is 3-5DB, which is not related to the order of order, but it is probably a approximate reference.

9. The obvious advantages of third -generation products (actual effects):

As long as the user needs to understand the specific technical indicators of the three -generation chip, it is more important to observe whether there is the following characteristics.

(1) Fast positioning time: Regardless of the cold start, Wen Qi, and the heat, the re-capture time is almost 5-30 seconds (compared to the second generation). In fact, most users are not worse than these ten seconds.

(2) High sensitivity: that is, in high -rise buildings, shade, underpass, cover files, Suidong, windows, cars, and even under the chassis of the car, you can quickly position more than 4 satellites.It is often said that it can be positioned a bit (single -star positioning), that is, "Give some Sunshine".

(3) Anti -interference performance: high -voltage lines, electric fields, magnetic fields, high -speed dynamics, microwaves, mobile phones, can still work properly in the environment of frequency interference.

(4) Low power consumption and power saving: reduce power consumption, and even have sleep state (static does not work), which can save power and improve product standby time.

(5) Small volume, good performance and price comparison: small volume and light weight. This is the needs and development trend of society, which can expand more application scope and field.In fact, the price of the three-generation chip should be the same as the second generation, or even lower, but the function is much improved. T-38 (16 channels, 3rd generations) 200-300 yuan/block.

1. How to use Outdoor mobile power supply

1. Take out the Outdoor portable power supply and turn on the "AC On/OFF" switch. At this time, the display screen is on, proving that the Outdoor power AC 220V output function is turned on and the power supply starts to work.

2. Insert the power supply equipment that need to be used into an output socket on the Outdoor portable power supply, and turn on the switch of the electric equipment to start power supply.

3. After use, turn off the power switch and unplug the power equipment.

2. precautions for the use of Outdoor mobile power supply

1. Please read the manual carefully before use.Improper use will cause abnormal phenomena such as damage, overheating, smoking, and fire.

2. Do not throw, impact or rub the products violently, so as not to cause other abnormal phenomena such as depression, perforation, cracking, deformation, and corrosion.If the above situation has already occurred, stop using it immediately.

3. In addition to the charging cable configured in this machine, please do not use other methods or machines to charge Outdoor mobile power.If you use other methods to charge the product, please read the instruction manual carefully in advance.

4. Can not be used in low temperature environments for a long time. If the Outdoor mobile power supply is transferred from a warm environment to a low -temperature environment, or in a low temperature environment for a long time, it may be condensed on the PCB board with a certain temperature.When the dew phenomenon is more serious, the short -circuit may occur.Therefore, everyone should pay attention to changes in temperature. It is best to use above 0 C, which is safer and durable.

5. Don't throw, knock, and shake the power supply at will.The severe shaking can easily lead to dislocation of the internal structure of the lithium battery, causing short circuits, and burning the battery.If the battery core is not good or the control circuit does not do well, it is likely that the lithium battery will spontaneously ignite or even explode.

6. The Outdoor mobile power supply that is not used frequently should be charged and discharged once a month to extend the service life of the mobile power supply.If you do not need to move the power for a long time, it is best to keep 50%of the power for storage.

1. What wheel is easy to use in front

The pole of the front is a type of hand and the sea. The biggest feature of this fishing rod is that there are fishing wars and wire rings. Other aspects are almost the same as the hand pole. In fact, many front poles are modified by the fishermen.fishing with a pole is more advantageous than the hand pole. The following editors will be used for science to use the wheels to match the pole!

The front pole should be equipped with a special front wheel. If the rate of medium fish is relatively high, it must be equipped with a number of front -to -line wheels.There are also many fishermen who are equipped with micro -lead wheels in front of them. Although the key points, it is very convenient to use.

2. What is the matching method of the lines of the stab

There is a problem that has always troubled us: that is the small hook. If you encounter a big thing, it will inevitably destroy the line and run the fish.what to do?This tests the line group matching method of the pole.

First install the pole and wheel, and the main line of Taiwan fishing is generally selected by 1.0-2.0#directly, around the front wheel, the front end line heads through each metal coil of the pole, and the online head is tied to the pole head rope.

Then, as the Taiwan fishing, seven space Beans, a drifting seat, a fast lead, a 8-character ring, connected to 0.4-1.5#sub-line dual hooks.

Then take the Fishing rods all seasons, the disclosure is adjusted, the drift bait, and the same fishing method as the Taiwanese fishing. Such a line group matching method is that you are not afraid of encountering big things.

The above is the whole content of what wheel is easy to use and the line group matching method of the front pole. I hope to help you!

[Use of astronomical Telescope] How to use the astronomical Telescope to use the correct use step and guide

1. Install a astronomical Telescope according to the instructions.

2. Regarding the focus of the Telescope and the calibration of the cross -line mirror

Loose two fastening screws on the eyepiece.Take out the low -duty mirror and put it on the eyepiece to pick up the cylinder, and then tighten the screw.The adjustment of the focusing knob can obtain a fuzzy image of an object A in the distance, and then slowly adjust the coke knob back and forth until the object image is clear.The Telescope has accurately adjusted the focal length, and now it can be observed with a star -seeking mirror.If the astrology mirror is not at the focal length, turn the eye mirror until a clear scene appears.When the object of object A you see on the Telescope is not in the center of the star mirrors, according to the following method: tighten or release the screw on the star -seeking mirror support, so that the star -seeking mirror up and down, left and right workers, left and right workers, left and right workers, left and right workMove obliquely.When the object of the object A appears in the center of the cross line, your star -seeking mirror is ready, and finally the three screws are tightened.Then replace the low -power mirror with a high -power mirror and repeat the above program.If the center of the image observed under the maximum mirror and the cross -line center of the star -seeking mirror, your star -seeking mirror is adjusted.Now you can quickly find the celestial body you want to observe.In extremely special circumstances, star -seeking mirrors may need to be adjusted.

3. precautions

A. Under any circumstances, first look for objects with a star -seeking mirror, because the perspective of the star -seeking mirror is greater, which can greatly accelerate your coarse tone.

B. Under normal circumstances, first install a low multiplier mirror to gradually increase the multiple you need, and you need to make the necessary focus when you change the mirror.

C. Don't be troubled by the upper and lower, left and right images that you see, this is a normal situation for astronomical Telescopes.

4. Effective observation notice

If the Telescope gets outdoors for the first time in air with lower indoor temperature, it must be used for a few minutes-because the temperature difference will make the lens blindfold.This phenomenon will disappear after 15-20 minutes.If your eyelids or fingers touch the eyepiece, the cloth that can't afford the hair will be gently wiped to see the mirror to prevent blurred images.It takes about 30 minutes to enlarge your pupils to adapt to darkness, so use a Telescope at night. After half an hour, you can see a much dark celestial body.

5. Various factors that may affect the observation results

Observation results are not all taken in the optical properties of the Telescope, and many factors also affect the quality of the image.

A. The atmosphere surrounded by the earth is always moving. This kind of atmospheric movement and rotation will cause bad images at a high rate. Perhaps after a few nights, the observation will improve.

B. The heat on the surface of the earth will also cause the fluctuations of the air and make the image distort and deform, resulting in poor observation.

C. The observation angle of the Telescope and the star and horizon has a great impact on the observation effect: if the star body is close to the horizon, the goal will be blurred.

D. Pollution of light sources: use your Telescope (such as under street lights, under room Lights, etc.) as much as possible in a light -free environment, high -mortar astronomical Telescope is very sensitive to light.Even more obvious, it seems that many stars will disappear over the urban area.

E. Moonlight may also be another factor that affects observation. The dazzling full moon or bright moonlight will blur the nearby stars or planets, and the moon itself is the best observation state between darkness and Tianming.

f. Try to avoid observation from opening the window (let alone observation of closed windows), especially in the cold season, the indoor and outer temperature difference can be worse, which will make the observation quality worst.

G. The cloud layer accumulated in the sky cannot penetrate the observation, but this cloud will often move.

H, star flashes are caused by air convection, which will also affect observation.

Remember, in any case, do not directly observe the sun through a star -seeking mirror or main lens barrel, otherwise it will seriously damage your eyes.

How to raise red worms

1. Breeding conditions

When breeding red worms, prepare a glassware, then put the selected red worms into it, and then inject clean and sterile natural water. If you want to use tap water, it is best to place tap water in the sun 2-3God, remove the chlorine gas in it to prevent red insects from growing poorly.

2. Control light source

The growth of red worms is inseparable from light. Lack of light sources can cause red worms to breathe and suffocate death. It is best to hang a 5 -watt Light bulb above the container to provide adequate light irradiation to the red worm to make them free.Breathing, healthy growth.

3. Water quality regulation

In the process of breeding red worms, you need to replace the water once a day to keep the water clean. In the process of changing water, clean the red worms and containers to clean the mucus to avoid breeding bacteria. It is best to control the depth of the breeding water.About 3-5 cm, deepen the water level at night, playing a warmth.

4. Feeding bait

Red worms mainly eat Organic fertilizer, and like some sour, sweet feed.In general, you need to be fed once every three days.You can use rice bran, sludge, pigeon dung, sawdust and other fermentation into feed.

5. Breeding management

Natural air flow should be performed in the breeding venue, and it can be exposed to the air, which can effectively improve the oxygen content.When the temperature is too high, you can use some artificial methods to increase the oxygen content of the breeding venue. When the temperature is below zero, frozen phenomenon will occur.At this time, they are easily frozen to death. They can use some other warm measures to reduce the icing of the water surface so that they can effectively grow them.

How to save time for red worms

1. Pick up insects

First, the bugs I bought are as much as I have just entered, so that they can be fed for a long time and can not die for a long time.

2, density

The density of insects should not be too large. If the density of the bugs is high, it is easy to die. Generally, it is raised with one to two or two cm stainless steel pots. The density is just right and the water is basically full.

3. Change water

The water needs to be changed every day, and placed in a cold place. If there is no cold place, place it in the shade window sill near the window.board, this can be insulated. It is best to keep the water of the red worm. The water temperature in the water in the pot is close, and the worm is easier to live.

4. Wash

The first is to wash the pot. After changing the red worm into the sieve every time the water is changed, the basin must be washed with water. At this time, some of the pots will be stained on it.Go down, rinse the pot. The second is to wash the insects, connect the water from the pot, and rinse the bugs in the sieve with water with water, and the mucus and dirty things on the insects.

5. Others

Pick out the dead bugs before changing the water or before changing the water to ensure that there is no blood water in the water polluting the water.