Ahd- anonymous HD, that is, analog high resolution. Regarding HD, simply speaking, in the field of security, formats with physical resolution above 720P are usually called HD, or HD for short. The vertical resolution of the picture is 1080i, 720P or 1080P. 1080i60 means that the resolution is 1920× 1080, and interlaced scanning is adopted to present 30 complete pictures per second; 720P60 means that the resolution reaches 1280×720, and 60 complete pictures are presented every second by progressive scanning; 1080P60 means that the resolution reaches 1920× 1080, and 60 complete pictures are presented every second through sequential scanning. Based on AHD protocol, AHD uses analog coaxial cable to transmit progressive HD video, and its chip is used in surveillance security camera.

According to You Shi, AHD is as simple and convenient as traditional equipment. Relevant publicity materials show that it can use ordinary 75-3 coaxial cable for high-definition lossless transmission up to 500 meters, which breaks through the transmission limit of the existing high-definition video transmission technology, and can realize low cost, long distance, no delay, high efficiency, anti-interference and easy realization of megapixel high-definition video transmission.

Some manufacturers claim that AHD follows the way and method of analog standard definition transmission, which can reduce the complexity of construction deployment, reduce the cost of auxiliary materials and maintenance complexity, and the technical requirements for construction personnel; It is suitable for upgrading the old system, and the SD can be easily upgraded to HD without changing the original system. In addition, the quality of high definition and the price of standard definition make AHD have great development space in both civil and industrial markets.