COFDM Wireless Video Sender en Untfanger
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COFDM Wireless video transmitter and receiver Dimension
2-watt PA COFDM Wireless Video Transmitter
Grutte: 90x65x22mm
The most recent advancements in COFDM (Kodearre Ortogonale Frequency Division Multiplexing) wireless video transmitter and receiver technology have transformed how video is transmitted and received. COFDM is a modulation technique that allows digital data to be transmitted over a wide range of frequencies, resulting in a more reliable signal and improved data transmission.
We use COFDM technology in numerous applications, such as digital television, wireless video oerdracht, en digitale radio. It’s also found in military and aerospace applications like satellite communications and unmanned aerial vehicles.
Úteinlik, recent advancements in COFDM wireless video transmitter and receiver technology have transformed the way video is transmitted and received. This technology has enabled high-definition video transmission over wireless networks, as well as video transmission over a variety of networks and devices. The use of advanced coding techniques, such as forward error correction (FEC) and adaptive modulation, has enabled this.
5-watt PA COFDM Wireless Video Transmitter
5-Watt PA COFDM-912T Weight
Package for one full set of the COFDM Wireless Video Transmitter
FAQ of the COFDM Wireless Video Transmitter and Receiver
Hoi, I am looking for a long-range hd video transmitter with hdmi input and a receiver with hdmi output.
Would you like a ien rjochting of twa-wei systeem? As long as you need to send the video, do you still need to send the control operation of the drone?
Only transmit and receive in a surveillance center. The idea is to use the HDMI output of the remote control and retransmit it to the central. The drone has a system to transmit over the internet, but there is no internet in the desert, so we need to retransmit but not with the internet.
OK, our one-way long-range wireless video transmission solution is the base of COFDM technology (similar to DVB-T digital TV broadcasting). It is not on the base of the Internet.
Does this COFDM wireless video transmitter and receiver have AES 256 of 128 fersifering? the output format is full hd?
Ja, COFDM-912T supports AES 128 fersifering. Please notify us to plus a Parameter Configuration board for setting the AES128 password when you are placing the order. It is optional to buy.
The COFDM-912T transmitter only supports SD720P Video input. So even if the receiver has HDMI output, it cannot output real 1080P high-definition video, only 720P.
If you have very high requirements on the definition of picture output, I suggest you choose a model that both the transmitter and receiver support 1080P, COFDM-908T
Can it reach 30 km around?
In the introduction of the wireless video transmission system, all the transmission distances mentioned are based on the visible range (DE). The 2WPA power amplifier supports 30 kilometers and is usually used on drones. The altitude is very high and the receiver is on the ground, so there is an obvious height difference between the transmitter and the receiver, and the wireless signal is transmitted in accordance with the waveform. The signal loss is small and other interference is very little clutter.
You mentioned that your usage scenario is that both the transmitter and receiver are on the ground, especially in desert areas, and there may be rolling sand dunes. Dêrom, the signal transmitted wirelessly is easily interfered with. So here are the suggestions:
1. Try to use a high-power transmitter, lykas 10 Watt of 20 Watts. Many of our ship customers use 20W transmitters.
2. Try to use a higher antenna or put the antenna on the roof or a nearby hill, and you can also increase the antenna tripod. Our clients always choose some 1.8-meter FRP omnidirectional fiberglass antennas.
3. If conditions permit, in repeater can also be added to enhance the signal strength and increase the transmission distance. The repeater can be fixed at a high place or on the roof of a moving car.
How to assemble the wireless video transmitter, kamera, and battery?
Kontrolearje asjebleaft de ôfbylding hjirûnder. 
There are two power connectors at the transmitter, the red connector is 12V output for the camera, and the black connector is 12V input.
What is the lag or delay in milliseconds of your COFDM-912T?
200-300ms with a regular camera and monitor.
Normal camera and screen have a delay of 200 millisekonden, rjochts?
With our 100 millisekonden, it’s about 300 nei 400.
We also have one with 30 millisekonden, but the price is 6 times that
300 milliseconds is acceptable if your plane has an automatic obstacle avoidance function.
I noted your transmitter can support up to 30 kilometers in LOS. How far will it support in the NLOS environment?
It’s hard to say the range of non-line-of-sight use, it depends on how many obstacles are in the middle. It is difficult to transmit if fully surrounded metal or mountains block it.
The test environment is unique, and the distance obtained from the test is also different. We can’t make any guarantees or promises about this.
We are a company that offers a solution to some rural areas here in the Philippines to monitor their rivers. If we purchased a 2W(30km) in the NLOS location, it could be reduced to 20km or more?
It is hard to say, it should depend on the obstacles between the transmitter and receiver. We don’t test it in your use environment, So I can’t tell you.
The same product will be interfered with differently in different environments, and the transmission distance is hard to say. Only the actual test will know.
Buyer: Actually, we have installed a radio transceiver that gathers a data sensor and transmits its data to an 18km distance center command. The operation is smooth and ok.
The same place we’re going to put up the device that we will buy from you.
As you have said, only an actual test will answer all of my questions.
Can the COFDM-912T TX device output separate serial data?
Data can only be transmitted in one direction from the transmitter to the receiver.
If you need to transmit data in both directions, you need to add a digital radio telemetry. (wireless data transceiver).
I would like to know if the transmitter can also output serial data on what the camera is capturing. Other than RF does it have a separate rs232 output for the transmitter?
Ja, COFDM-912T supports transferring the serial data for you. Kontrolearje asjebleaft de ôfbylding hjirûnder. 
In this module where I can put up the camera? What type of camera is suited for this device?
The black one on the left shows a little bit of the above picture, which is connected to the camera.
It supports a 720p CVBS composite AV camera. or any HDMI camera by HDMI to AV converter box.
How can I let the transmission still work well if I remove the menu and panel board from the receiver?
Is there any way to disable the control panel so that the receiver can see the video from the transmitter?
If I remove the control panel on the receiver, the receiver does not see the signal from the transmitter.
Antwurd: Please check the FAQ in the below link.
https://ivcan.com/p/cofdm-video-transmitter-receiver-av-in-hdmi-out/#accordion-item-6._i_have_changed_the_parameter_on_the_configure_board_tool,_why_it_is_not_saving_when_i_restart?
I guess that you did not save the frequency, after you remove the menu on the receiver, the system will be back to the default frequency of 340Mhz. So you can not get the signal.
If GPS and TX are separated less than 1 meter – GPS is jammed. COFDM-912T has significant noise in GPS l1 and l2 freq. Do you have any low-pass filters to solve this problem?
Hoi! We did extensive testing before ordering a bigger batch. And faced issues if combining the COFDM-912T transmitter with GPS.
Antwurd:
1. If you buy it again, I can add a low pass filter in the transmitter inside free. I can also provide an external low-pass filter for you for free.
2. “Do you know what insertion loss is in non-filtered frequency?”, Antwurd: max 0.6db
3. “Do you know what dBm loss is pass frequency?” 0.4DBM
COFDM-912T Customize Development
2 Watts default 595Mhz with 1.8-meter transmitter and receiver antenna
The client told us that his application details, the transmitter and receiver, are both used on the ground. In order to enhance the wireless transmission distance and avoid other signal interference, I recommend that both the transmitter and receiver antennas use 1.8-meter fiberglass antennas.
It was the first time the customer took the sample for testing, so he used the default two-watt amplifier and 595 MHz frequency.
The customer requires that the transmitter have an HDMI output so that he can transmit the received video to other devices. Tagelyk, in order to support HDMI input, I also matched an HDMI to CVBS RCA AV converter box.
The customer has added an optional parameter adjustment tool, the main function of which is to modify the transmitter’s transmission frequency and impedance. You can also add a password to the wirelessly transmitted video to encrypt the video of the transmitter. We must enter the same password on the receiver to decode the video to improve the security of the video.
Change COFDM Transmitter to 200 mW NET, with a power switch of the cooling fan for body wear
Customize a video on-off switch on the COFDM Transmitter for audio-only wireless transfer.
Here is the test video for this client’s requirement, added a video on-off switch at the 10-watt PA wireless video transmitter to transfer the audio only.
Here is a video to show you that we can add one video on-off switch on the COFDM wireless video audio transmitter.
Video on, then the transmitter will transfer the video and audio at the same time.
Video off, then the transmitter will transfer the audio only.
If you have any project or need to customize the function of the wireless video transmitter and receiver, nim dan kontakt mei ús op.
The default power amplifier is 2-watt, we also make a 10-watt PA inside, to support long-range and transfer more extended distances.
2 Watts default 595Mhz with Yagi Directional Antenna and Omnidirectional antenna
300 Watts power amplifier modified 230Mhz COFDM wireless video transmitter and receiver
FAQs
- Ja, it frekwinsjeberik kin feroare wurde fan 170Mhz (better fan 220Mhz) oan 860Mhz. Sa kin it goed wurkje op 260Mhz band.
- De frekwinsje moat oanpast wurde oan deselde op 'e stjoerder en ûntfanger. Fan oarsaak, de Power Amplifier en antenne frekwinsje moatte feroarje deselde frekwinsje. (Jo moatte in krêftfersterker en antenne keapje foar de stjoerder en ûntfanger om te foldwaan oan jo feroare frekwinsje).
- Om de gefoelichheid fan ferstjoeren en ûntfangen te ferbetterjen, de frekwinsje bânbreedte wurdt algemien makke hiel smel (sintrum frekwinsje ±15MHz, dus bânbreedte moat 30Mhz wêze). De machtfersterker fan 'e stjoerder en de frekwinsje fan' e antenne wurde spesjaal oanpast neffens de frekwinsje dy't jo nedich binne.
- It is it bêste as jo in bestelling pleatse, fertel my asjebleaft hokker soarte wurkfrekwinsje jo nedich binne. Us yngenieurs sille de frekwinsje fan 'e stjoerder en ûntfanger oanpasse, en feroarje ek de PA en oanpaste antenne neffens dit frekwinsjeberik om de bêste gefoelichheid te garandearjen en de langste oerdrachtôfstân te stypjen.
- De standert frekwinsje is 590Mhz, Mei 30Mhz (+/-15MHz), jo kinne it feroarje sûnder de Power Amplifier en antenne te feroarjen. Bygelyks, 578MHz, 584MHz, 590MHz, 596MHz, en 602Mhz.
- As jo de stjoerderfrekwinsje en bânbreedte moatte wizigje, jo moatte in spesjale ark fan de parameter konfiguraasje board, sjoch asjebleaft de ôfbylding hjirûnder, it is gjin standert accessoire, keapje it asjebleaft tsjin in ekstra kosten of nim kontakt mei ús op foardat jo bestelle.
Ja, it stipet om de fideo- en UART-gegevens te ferstjoeren fan de stjoerder en ûntfanger.
As it is ien-wei oerdracht, sadat it it kontrôlekommando net fan 'e ûntfanger nei de stjoerder kin stjoere.
As jo kontrôlekommando's of oare gegevens fan 'e ûntfanger moatte ferstjoere om oare apparaten te kontrolearjen lykas kamera's of drones by de stjoerder, jo kinne in set goedkeape digitale oerdrachtapparatuer tafoegje, kontakt mei ús opnimme, en wy kinne it foar jo oanpasse.
Kontrolearje asjebleaft de UART-definiearje op 'e stjoerder en ûntfanger op' e ûndersteande keppeling. Fertel my asjebleaft as jo in leadkabel hawwe wolle. (standert is nee)
De standert Power Amplifier fan de stjoerder is 2 Watts, sadat it kin stypje 30 KM op line-of-sight.
De foto hjirûnder is ús testte ôfstân fan 'e berch nei de see.
As jo in langer berik wolle ferstjoere, jo kinne fergrutsje de macht fersterker. Neist ien watt en twa watt, wy kinne ek meitsje 5 watts, 10 watts, en 20 watt foar jo kar. Gruttere fersterkers fereaskje ek gruttere batterijen en aktuele stipe.
Foar 20W PA, de macht oanbod moat wêze 24 ~ 28V. Allinnich by 28 volt kin de macht fersterker berikke de bêste workability.
Us yngenieur kin de frekwinsje feroarje nei 300Mhz fan 'e standert 590Mhz, De antenne, en PA yn it pakhús binne 590Mhz, 300Mhz hat twa wiken nedich om oan te passen, sadat de levertiid langer nedich is dan ús standert 590Mhz.
Stap 1: Druk asjebleaft op OK en de rjochter knop tagelyk, in menu fan oft jo wolle opslaan ferskynt op it skerm.
Stap 2: Druk op OK om Ja te kiezen om op te slaan.
Remind, brûk asjebleaft de gruttere of langere antenne as jo projekt it talit, it kin bettere ûntfangstprestaasjes krije yn it gruttere berik.
De standert folsleine set
- SD stjoerder ( PA 0.5W, 1de, 2de, 5de, 10de, 20de, 50W opsjoneel neffens jo bestelling fraach)
- SD-stjoerder antenne
- HDMI CVBS útfier ûntfanger mei parameter kontrôle menu en lyts skerm
- 0.8-meter Untfanger antenne 1 pcs. (D'r binne twa soarten ynstallaasje of fixaasje fan 'e antenne: 1. magnetyske sucker basis antenne, 2. standert U-type clamp FRP fiberglass antenne )
- Fakultatyf, parameter konfiguraasje board foar de draadloze fideostjoerder.
(As jo in magnetyske suckerbasisantenne nedich binne, de ekspresje of ferfierder tinkt dat de magnetyske produkten har fleantúchfeiligens bemuoie sille, sadat de ferstjoerkosten heger binne as in U-type klemantenne. )
De standert folsleine set pakket diminsje
- 84*21*12CM
- Bruto gewicht 4,5 kg
- As jo mear dan 100 sm-antenne en magnetyske suckerbasisantenne kieze, Guon frachtferhierders sille ekstra fergoedingen ophelje, lykas ekstra lange fergoedingen en ekstra fergoedingen foar sterke magnetyske items.
- De stjoerder parameter konfigurearret board is oars as dy op 'e ûntfanger. De firmware op de parameter konfiguraasje board wie oars as de stjoerder en ûntfanger, se kinne net trochinoar brûkt wurde.
- De stjoerderparameter konfigurearret board kin de sinjaaldemping op 'e stjoerder oanpasse. Per 0.3db sil de 0.5W PA ferminderje.
Fraach: Is it mooglik om te feroarjen de outpout macht (ynterne PA 0,5 w, 1 w, 2 w) fia de konfiguraasje board?
- Lykas hjirboppe beäntwurde, jo kinne de útfierkrêft oanpasse troch de parameters fan ATTEN yn te stellen fia it ark foar parameterkonfiguraasjeboerd op 'e stjoerder. (Dit ark omfettet it standertpakket net, jo moatte ynformearje dat jo dit ark wolle hawwe as jo bestelle)
- As jo keapje 2W PA, dan kinne jo it 0.5W ynstelle, 1de, mar kin it net feroarje nei 5W.
- Wy kinne it ek meitsje nei 5W, 10de, 20de, en 50W as jo moatte stypje lange-range.
Nee.
Dizze draadloze fideostjoerder stipet allinich CVBS-kamera as fideo-ynfier, oare soarte fan fideo kamera hat in ekstra converter doaze nedich.
Nee. It is COFDM (DVB-T) technology.
Dat it COFDM-frekwinsjeberik is 170-860Mhz. It kin stypje 477, 610, 675, 724, 816MHz, mar kin net stypje 970, 1180, 1230 MHz.
Us spesjale modelstjoerder kin alle boppesteande berikken stypje, mar de ûntfanger moat it downconverter-blok brûke.
Om ús draadloze útstjoersysteem in breder berik en bettere sinjaalsterkte te stypjen, wy stelle oer it algemien de bestjoeringsfrekwinsje op in bepaald punt (170~860Mhz), en syn stipe berik is mar plus of minus 15Mhz. Bygelyks, it sintrum frekwinsje is 590Mhz, max stipe frekwinsje berik moat wêze 575Mhz ~ 605Mhz, De PA en antenne wurde spesjaal oanpast neffens dizze sintrumfrekwinsje.
How to add a low-pass filter chip to the transmitter?
Some customers reported that when the distance between our transmitter and the GPS antenna is less than one meter, the transmitter will interfere with the work of the GPS through the transmitting antenna.
GPS satellite signals are divided into L1 and L2, with frequencies of 1575.42MHZ and 1228MHZ respectively. Our transmitter frequency is 595Mhz by default. If we encounter this situation, we can consider adding a low-pass filter, which means frequencies below 600Mhz. Frequencies above 600 MHz can be suppressed to avoid interference with other emitting electronic products.
There are two ways to add a filter. One is to add a filter IC to the COFDM-912T transmitter board, and the other is to add a filter box outside the transmitter. The down-pass filter can suppress frequencies below a certain frequency point, and the wave-pass filter can suppress the frequencies below a certain frequency point by allowing them to pass through.
