COFDM simsiz video uzatuvchi va qabul qiluvchi
Mundarija
COFDM Wireless video transmitter and receiver Dimension
2-watt PA COFDM Wireless Video Transmitter
hajmi: 90x65x22 mm
The most recent advancements in COFDM (Kodlangan ortogonal chastotali bo'linish multiplekslash) 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, simsiz video uzatish, va raqamli radio. It’s also found in military and aerospace applications like satellite communications and unmanned aerial vehicles.
Nihoyat, 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.
Would you like a bir tomonga yoki ikki tomonlama tizim? 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 yoki 128 shifrlash? the output format is full hd?
ha, COFDM-912T supports AES 128 shifrlash. 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. shu sababli, the signal transmitted wirelessly is easily interfered with. So here are the suggestions:
1. Try to use a high-power transmitter, kabi 10 Vatt yoki 20 Vatt. 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, a 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?
Quyida rasm tekshiring. 
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 millisekundlarda, o'ng?
With our 100 millisekundlarda, it’s about 300 uchun 400.
We also have one with 30 millisekundlarda, 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?
ha, COFDM-912T supports transferring the serial data for you. Quyida rasm tekshiring. 
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.
javob: 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 metr – 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.
javob:
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?”, javob: 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. Xuddi shu paytni o'zida, 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, bizga murojaat qiling.
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
Tez-tez so'raladigan savollar
- ha, chastota diapazoni 170 MGts dan o'zgarishi mumkin (yaxshiroq 220 MGts dan) 860 MGts gacha. Shunday qilib, u 260 MHz diapazonida yaxshi ishlashi mumkin.
- Chastotani uzatuvchi va qabul qiluvchida bir xil qilib o'zgartirish kerak. Sabab bilan, Quvvat kuchaytirgich va antenna chastotasi bir xil chastotani o'zgartirishi kerak. (O'zgartirilgan chastotangizni qondirish uchun uzatuvchi va qabul qilgich uchun quvvat kuchaytirgich va antenna sotib olishingiz kerak).
- Etkazish va qabul qilishning sezgirligini oshirish uchun, chastota tarmoqli kengligi odatda juda tor qilingan (markaziy chastota ±15MGts, shuning uchun tarmoqli kengligi 30 MGts bo'lishi kerak). Transmitterning quvvat kuchaytirgichi va antennaning chastotasi sizga kerak bo'lgan chastotaga qarab maxsus moslashtirilgan.
- Buyurtma berganingizda eng yaxshisidir, Iltimos, menga qanday ish chastotasi kerakligini ayting. Bizning muhandislarimiz uzatuvchi va qabul qiluvchining chastotasini o'zgartiradilar, va shuningdek, ushbu chastota diapazoniga muvofiq PA va maxsus antennani o'zgartiring eng yaxshi sezgirlikni ta'minlash va eng uzoq uzatish masofasini qo'llab-quvvatlash.
- Standart chastota 590 MGts, 30 MGts bilan (+/-15MGts), siz uni quvvat kuchaytirgich va antennani o'zgartirmasdan o'zgartirishingiz mumkin. Masalan, 578MGts, 584MGts, 590MGts, 596MGts, va 602 MGts.
- Transmitter chastotasi va tarmoqli kengligini o'zgartirish kerak bo'lsa, Sizga parametrlarni sozlash panelining maxsus vositasi kerak, iltimos, quyidagi rasmga qarang, u standart aksessuar emas, iltimos, uni qo'shimcha narxda sotib oling yoki buyurtma berishdan oldin biz bilan bog'laning.
ha, u video va UART ma'lumotlarini yuborishni qo'llab-quvvatlaydi uzatuvchi va qabul qiluvchidan.
Chunki u bir tomonlama uzatish, shuning uchun u boshqaruv buyrug'ini qabul qilgichdan uzatuvchiga yubora olmaydi.
Transmitterdagi kameralar yoki dronlar kabi boshqa qurilmalarni boshqarish uchun qabul qiluvchidan boshqaruv buyruqlari yoki boshqa ma'lumotlarni yuborish kerak bo'lsa, arzon raqamli uzatish uskunalari to'plamini qo'shishingiz mumkin, Biz bilan bog'lanish, va biz uni siz uchun sozlashimiz mumkin.
Iltimos, quyidagi havolada uzatuvchi va qabul qiluvchidagi UART taʼrifini tekshiring. Iltimos, qo'rg'oshin kabeliga ega bo'lishni xohlaysizmi, ayting. (standart yo'q)
Transmitterning standart quvvat kuchaytirgichi 2 Vatt, shuning uchun qo'llab-quvvatlashi mumkin 30 Ko'rish chizig'ida KM.
Quyidagi rasm tog'dan dengiz qirg'og'igacha bo'lgan sinovdan o'tgan masofamiz.
Agar siz uzoqroq masofani uzatmoqchi bo'lsangiz, quvvat kuchaytirgichini oshirishingiz mumkin. Bir vatt va ikki vattga qo'shimcha ravishda, biz ham qila olamiz 5 vatt, 10 vatt, va 20 Sizning tanlovingiz uchun vatt. Kattaroq kuchaytirgichlar ham kattaroq batareyalar va joriy yordamni talab qiladi.
20 Vt PA uchun, quvvat manbai 24 ~ 28 V bo'lishi kerak. Faqat soat 28 volt quvvat kuchaytirgichi eng yaxshi ish qobiliyatiga erisha oladi.
Bizning muhandisimiz chastotani standart 590 MGts dan 300 MGts ga o'zgartirishi mumkin, Antenna, va ombordagi PA 590Mhz, 300Mhzni sozlash uchun ikki hafta kerak bo'ladi, shuning uchun etkazib berish muddati standart 590 MGts dan ko'proq vaqt talab qiladi.
Qadam 1: Iltimos, bir vaqtning o'zida OK va o'ng tugmani bosing, ekranda saqlash yoki saqlamaslik menyusi paydo bo'ladi.
Qadam 2: Saqlash uchun OK tugmasini bosing.
Eslatma, Agar loyihangiz imkon bersa, kattaroq yoki uzunroq antennadan foydalaning, kengroq diapazonda yaxshiroq qabul qilish ko'rsatkichlariga ega bo'lishi mumkin.
Standart toʻliq toʻplam
- SD transmitter ( PA 0,5 Vt, 1W, 2W, 5W, 10W, 20W, 50W buyurtma talabiga ko'ra ixtiyoriy)
- SD transmitter antennasi
- Parametrlarni boshqarish menyusi va kichik ekranli HDMI CVBS chiqish qabul qiluvchisi
- 0.8-metr qabul qiluvchi antenna 1 dona. (Antennani o'rnatish yoki o'rnatishning ikki turi mavjud: 1. magnit so'rg'ichli asosiy antenna, 2. Default U tipidagi qisqich FRP shisha tolali antenna )
- ixtiyoriy, simsiz video uzatuvchi uchun parametr konfiguratsiya taxtasi.
(Agar sizga magnit so'rg'ichli antenna kerak bo'lsa, ekspress yoki tashuvchi magnit mahsulotlar ularning samolyot xavfsizligiga xalaqit beradi deb o'ylaydi, shuning uchun yuk tashish narxi U tipidagi qisqich antennadan yuqori. )
Standart toʻliq toʻplam oʻlchami
- 84*21*12SM
- Yalpi og'irligi 4,5 kg
- Agar siz 100 sm dan ortiq antenna va magnit so'rg'ich tayanch antennasini tanlasangiz, Ba'zi ekspeditorlar qo'shimcha haq olishadi, kuchli magnit buyumlar uchun qo'shimcha uzoq to'lovlar va qo'shimcha to'lovlar kabi.
- Transmitter parametri platani sozlash qabul qilgichdagidan farq qiladi. Parametrlarni sozlash taxtasidagi proshivka uzatuvchi va qabul qilgichdan farqli edi, ularni bir-birining o‘rnida ishlatib bo‘lmaydi.
- Transmitter parametri platani sozlaydi, transmitterdagi signalning zaiflashishini sozlashi mumkin. 0,3 db boshiga 0,5 Vt PAni kamaytiradi.
savol: Chiqish quvvatini o'zgartirish mumkinmi? (ichki PA 0,5 w, 1 w, 2 w) konfiguratsiya paneli orqali?
- Yuqorida javob berilganidek, transmitterdagi parametrlarni sozlash paneli vositasi orqali ATTEN parametrlarini o'rnatish orqali chiqish quvvatini sozlashingiz mumkin.. (Ushbu vosita standart paketni o'z ichiga olmaydi, buyurtma berganingizda ushbu vositaga ega bo'lishni xohlayotganingizni bildirishingiz kerak)
- Agar siz 2W PA sotib olsangiz, keyin siz uni 0,5 Vt o'rnatishingiz mumkin, 1W, lekin uni 5W ga o'zgartira olmaydi.
- Biz uni 5 Vtga ham qila olamiz, 10W, 20W, va agar siz uzoq masofani qo'llab-quvvatlashingiz kerak bo'lsa, 50 Vt.
yo'q.
Ushbu simsiz video uzatuvchi faqat CVBS kamerasi yoki video kiritishni qo'llab-quvvatlaydi, boshqa turdagi videokamera uchun qo'shimcha konvertor qutisi kerak.
yo'q. Bu COFDM (DVB-T) texnologiya.
Shunday qilib, COFDM chastota diapazoni 170-860 MHz. Qo'llab-quvvatlashi mumkin 477, 610, 675, 724, 816MGts, lekin qo'llab-quvvatlamaydi 970, 1180, 1230 MGts.
Bizning maxsus model uzatgichimiz yuqoridagi barcha diapazonlarni qo'llab-quvvatlaydi, lekin qabul qiluvchi pastga aylantiruvchi blokdan foydalanishi kerak.
Simsiz uzatish tizimimizga kengroq diapazonni va yaxshi signal kuchini qo'llab-quvvatlashga imkon berish uchun, biz odatda ish chastotasini ma'lum bir nuqtaga o'rnatamiz (170~860 MGts), va uning qo'llab-quvvatlanadigan diapazoni faqat ortiqcha yoki minus 15MHz. Masalan, markaziy chastota - 590 MGts, maksimal qo'llab-quvvatlash chastota diapazoni 575Mhz ~ 605MHz bo'lishi kerak, PA va antenna ushbu markaz chastotasiga muvofiq maxsus moslashtirilgan.
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.
