Hidden Wireless Cameras Work

1. 

   Components of a Wireless Security Camera

   • A wireless security camera relies on communication between video transmitters and receivers. Most new digital-video cameras come with a built-in wireless feature that allows the cameras to connect to a computer or the device being used to receive the signal. The receiver must also maintain a wireless connection to a monitor or time-lapse recorder in order for the wireless security camera to capture the feed going into the receiver.

   Wireless Security Camera Frequencies

   • The communication between camera and receiver takes place at a frequency specific to both devices. Most wireless devices, cameras in this case, allow you to select from only four frequencies. Frequency limitations usually limit you to four cameras per location at a given frequency.

   Powering Your Wireless Security Camera

   • While the video signal that transfers the signal from the camera to the receiver and monitor is wireless, each of the devices (camera, receiver and monitor) still needs a power source. At this point, a totally "wireless" security camera setup is not available. Security cameras must be set up near electrical outlets.

1. Wireless Basics

   • A wireless camera may or may not be truly "wireless." Although some are powered by batteries, many actually need to be discretely plugged into the wall or otherwise attached to an electric system. They do use wireless transmission, however, which means that you do not have to run a cable from the camera to the receiver. This can make them more convenient to use and easier to hide.

   Detecting the Image

   • A wireless hidden camera creates pictures like any other digital video camera. Light comes through the lens, which focuses it on a small grid of light detectors. In a black-and-white surveillance camera, each detector simply gauges how much light there is at a particular place in the image. In a color camera, each detector only measures red, green or blue light, and then groups of three detectors are combined to show the color of light in a particular place. All of these individual photo detectors are then combined to make a complete picture. Some wireless hidden cameras also have a motion detector and a motor that automatically makes the camera follow any movement in the room. Other cameras just continue to focus fixedly on the same spot.

   Transmitting the Image

   • Wireless cameras have small radio transmitters on board. The camera turns the image into a radio signal on a particular frequency. The radio transmitter is typically not a large, powerful one, but a small one designed to broadcast the signal to a receiver in the same building. The receiver then picks up the signal and turns it back into an image.

   Using the Footage

   • The receiver can do different things with the image depending on its purpose. If the wireless camera is there for continuous surveillance, the image might be displayed along with the images from other cameras on a bank of video screens for a security guard to watch. The image can also be recorded, either to a computer hard drive or some other storage media. In some cases, the receiver will only store a couple of frames per second, creating a time-lapse picture of an area. This saves storage space and makes it easy to review the tape quickly later.