AHD CCTV stands for “Analog High Definition”. It is a new HD surveillance video standard for CCTV cameras and DVRs. AHD is a newly developed solution for transmitting full HD digital video in a surveillance system. The core concept of AHD is to deliver high definition video using digital TV (DTV) transmission. With AHD, high definition digital video can be transmitted easily over coaxial cables, twisted pairs, or simply over the air. Multiple 1080p30 and 1080p60 video streams can be easily transmitted using AHD over a single 5C2V/RG6 cable up to a length of 1000 meters without any repeater ( Up to 500 meters in case of 3C2V/RG59 ).
What type of cable do AHD cameras use?
AHD CCTV cameras are connected to DVRs using the same type of coaxial cable as traditional analog CCTV cameras , typically RG59 or RG6 coax cable. One of the advantages of AHD over HD-SDI CAMERAS (another HD over coax security camera standard), is that RG59 coax cable can be run long distances without video loss. So far in our experience, installers can reliably use RG69 coax cable up to a max distance of 800 feet for AHD cameras. AHD CAMERAS CAN ALSO USE UTP CABLE WITH VIDEO BALUNS to run cable up to 320 Meters / 960 feet with CAT5 cable.
AHD vs 960H Video Resolution?
The below images compare a video surveillance photo captured by a 960H CCTV camera with an AHD CCTV camera. Both of these cameras were connected to an IDVR-E8 HYBRID ANALOG / AHD CCTV DVR to capture the images. Each camera was displayed full screen at 720p resolution when the image was captured. Please click on the images to see a full-size view.
CCTV technology is extremely stable and prices are very affordable.
Some people in the surveillance industry thought that analog CCTV would have been phased out years ago. Around 2007, megapixel resolution IP cameras were gaining popularity. However, most found that IP cameras tend to be more difficult to setup and the pricing never came down enough for many to justify the higher resolution.
HD-SDI came to the surveillance industry about 2010 (it has been used to make movies and HDTV for years). Although I really like HD-SDI cameras, the acceptance of them has been limited. Some say it is because you can not run coax cable very long distances for HD-SDI and there is no support for video baluns (to use with UTP cable). The image quality of 1080p HD-SDI is outstanding though.
AHD seems to address the main issues that held back the other HD security camera types from taking over the analog CCTV market. Installers can use the same coax cable as traditional analog CCTV cameras and they work at the same max distance. Video baluns for AHD cameras are available for those that prefer to use UTP cable such as CAT5. Pricing on AHD cameras is only slightly more than analog.
Last, there are high quality hybrid DVRs available that let users use both AHD and analog CCTV cameras. This will allow security system owners to use their existing CCTV cameras and upgrade over time to HD, while keeping their DVR in place.
I expect AHD and CCTV to co-exist together for many years.