Pemancar dan Penerima Video Tanpa Wayar COFDM
Isi kandungan
COFDM Wireless video transmitter and receiver Dimension
2-watt PA COFDM Wireless Video Transmitter
saiz: 90x65x22mm
The most recent advancements in COFDM (Pegandaan Pembahagian Frekuensi Ortogon Berkod) 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, penghantaran video tanpa wayar, dan radio digital. It’s also found in military and aerospace applications like satellite communications and unmanned aerial vehicles.
akhirnya, 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
Hi, I am looking for a long-range hd video transmitter with hdmi input and a receiver with hdmi output.
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.
okey, 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 atau 128 penyulitan? the output format is full hd?
Ya, COFDM-912T supports AES 128 penyulitan. 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 (THE). 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. Oleh itu, the signal transmitted wirelessly is easily interfered with. So here are the suggestions:
1. Try to use a high-power transmitter, seperti 10 Watt atau 20 Watt. 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, yang pengulang 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?
Sila semak gambar di bawah. 
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 milisaat, betul?
With our 100 milisaat, it’s about 300 kepada 400.
We also have one with 30 milisaat, 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?
Ya, COFDM-912T supports transferring the serial data for you. Sila semak gambar di bawah. 
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.
jawapan: 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?
Hi! We did extensive testing before ordering a bigger batch. And faced issues if combining the COFDM-912T transmitter with GPS.
jawapan:
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?”, jawapan: 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. Pada masa yang sama, 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 PA, 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, sila hubungi kami.
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
Soalan Lazim
- Ya, julat frekuensi boleh ditukar daripada 170Mhz (lebih baik daripada 220Mhz) kepada 860Mhz. Jadi ia boleh berfungsi dengan baik pada jalur 260Mhz.
- Frekuensi harus diubah suai kepada yang sama pada pemancar dan penerima. Sebab, Penguat Kuasa dan frekuensi antena harus mengubah suai frekuensi yang sama. (Anda perlu membeli penguat kuasa dan antena untuk pemancar dan penerima untuk memenuhi frekuensi anda yang diubah).
- Untuk meningkatkan sensitiviti penghantaran dan penerimaan, lebar jalur frekuensi biasanya dibuat sangat sempit (kekerapan pusat ±15Mhz, jadi lebar jalur hendaklah 30Mhz). Penguat kuasa pemancar dan frekuensi antena disesuaikan khas mengikut frekuensi yang anda perlukan.
- Ia adalah yang terbaik apabila anda membuat pesanan, sila beritahu saya jenis kekerapan kerja yang anda perlukan. Jurutera kami akan mengubah suai frekuensi pemancar dan penerima, dan juga mengubah suai PA dan antena tersuai mengikut julat frekuensi ini untuk memastikan sensitiviti terbaik dan menyokong jarak penghantaran terpanjang.
- Kekerapan lalai ialah 590Mhz, Dengan 30Mhz (+/-15Mhz), anda boleh menukarnya tanpa mengubahsuai Power Amplifier dan antena. Sebagai contoh, 578Mhz, 584Mhz, 590Mhz, 596Mhz, dan 602Mhz.
- Jika anda perlu mengubah suai frekuensi pemancar dan lebar jalur, anda memerlukan alat khas papan konfigurasi parameter, sila lihat gambar di bawah, ia bukan aksesori lalai, sila beli dengan kos tambahan atau hubungi kami sebelum membuat pesanan.
Ya, ia menyokong untuk menghantar video dan data UART daripada penghantar dan penerima.
Memandangkan ia adalah penghantaran sehala, jadi ia tidak boleh menghantar arahan kawalan daripada penerima kepada pemancar.
Jika anda perlu menghantar arahan kawalan atau data lain daripada penerima untuk mengawal peranti lain seperti kamera atau dron di pemancar, anda boleh menambah satu set peralatan penghantaran digital yang murah, hubungi kami, dan kami boleh menyesuaikannya untuk anda.
Sila semak definisi UART pada pemancar dan penerima di pautan di bawah. Sila beritahu saya jika anda ingin mempunyai kabel plumbum. (lalai ialah tidak)
Penguat Kuasa lalai pemancar ialah 2 Watt, jadi ia boleh menyokong 30 KM pada jarak pandang.
Gambar di bawah adalah jarak kami yang diuji dari gunung ke tepi laut.
Jika anda ingin menghantar jarak yang lebih panjang, anda boleh meningkatkan penguat kuasa. Sebagai tambahan kepada satu watt dan dua watt, kita pun boleh buat 5 watt, 10 watt, dan 20 watt untuk pilihan anda. Penguat yang lebih besar juga memerlukan bateri yang lebih besar dan sokongan semasa.
Untuk 20W PA, bekalan kuasa hendaklah 24~28V. Hanya di 28 volt boleh penguat kuasa mencapai kebolehkerjaan yang terbaik.
Jurutera kami boleh menukar frekuensi kepada 300Mhz daripada 590Mhz lalai, Antena, dan PA di gudang adalah 590Mhz, 300Mhz memerlukan dua minggu untuk menyesuaikan, jadi masa penghantaran memerlukan lebih lama daripada 590Mhz lalai kami.
Langkah 1: Sila tekan OK dan butang kanan pada masa yang sama, menu sama ada menyimpan akan muncul di skrin.
Langkah 2: Sila tekan OK untuk memilih Ya untuk menyimpan.
Ingatkan, sila gunakan antena yang lebih besar atau lebih panjang jika projek anda membenarkan, ia boleh mendapatkan prestasi penerimaan yang lebih baik dalam julat yang lebih besar.
Set penuh lalai
- Pemancar SD ( PA 0.5W, 1The, 2The, 5The, 10The, 20The, 50W pilihan mengikut permintaan pesanan anda)
- Antena Pemancar SD
- Penerima output HDMI CVBS dengan menu kawalan parameter dan skrin kecil
- 0.8-meter antena Penerima 1 pcs. (Terdapat dua jenis memasang atau membetulkan antena: 1. antena asas penyedut magnet, 2. lalai Pengapit U-jenis antena gentian kaca FRP )
- pilihan, papan konfigurasi parameter untuk pemancar video wayarles.
(Jika anda memerlukan antena asas penyedut magnet, ekspres atau pembawa berpendapat produk magnetik akan mengganggu keselamatan pesawat mereka, jadi kos penghantaran lebih tinggi daripada antena pengapit jenis U. )
Dimensi pakej set penuh lalai
- 84*21*12CM
- Berat Kasar 4.5KG
- Jika anda memilih lebih daripada 100cm antena dan antena asas penyedut magnetik, Sesetengah penghantar pengangkutan akan mengenakan bayaran tambahan, seperti yuran tambahan panjang dan yuran tambahan untuk barang magnetik yang kuat.
- Parameter pemancar mengkonfigurasi papan adalah berbeza daripada yang terdapat pada penerima. Perisian tegar pada papan konfigurasi parameter adalah berbeza daripada pemancar dan penerima, mereka tidak boleh digunakan secara bergantian.
- Parameter pemancar mengkonfigurasi papan boleh melaraskan pengecilan isyarat pada pemancar. Setiap 0.3db akan mengurangkan 0.5W PA.
Soalan: Adakah mungkin untuk menukar kuasa keluar (PA dalaman 0,5 w, 1 w, 2 w) melalui papan konfigurasi?
- Seperti yang dijawab di atas, anda boleh melaraskan kuasa output dengan menetapkan parameter ATTEN melalui alat papan konfigurasi parameter pada pemancar. (Alat ini tidak termasuk pakej lalai, anda perlu memaklumkan bahawa anda ingin memiliki alat ini apabila anda memesan)
- Jika anda membeli 2W PA, maka anda boleh menetapkannya 0.5W, 1The, tetapi tidak boleh menukarnya kepada 5W.
- Kami juga boleh mencapai 5W, 10The, 20The, dan 50W jika anda perlu menyokong jarak jauh.
Tiada.
Pemancar video wayarles ini hanya menyokong kamera CVBS atau input video, jenis kamera video lain memerlukan kotak penukar tambahan.
Tiada. Ia adalah COFDM (DVB-T) teknologi.
Jadi julat frekuensi COFDM ialah 170-860Mhz. Ia boleh menyokong 477, 610, 675, 724, 816Mhz, tapi tak boleh sokong 970, 1180, 1230 Mhz.
Pemancar model khas kami boleh menyokong semua julat di atas, tetapi penerima perlu menggunakan blok penukar bawah.
Untuk membolehkan sistem penghantaran wayarles kami menyokong julat yang lebih luas dan kekuatan isyarat yang lebih baik, kami biasanya menetapkan kekerapan operasi ke titik tertentu (170~860Mhz), dan julat yang disokongnya hanya tambah atau tolak 15Mhz. Sebagai contoh, frekuensi tengah ialah 590Mhz, julat frekuensi sokongan maksimum hendaklah 575Mhz~605Mhz, PA dan antena disesuaikan khas mengikut frekuensi pusat ini.
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.
