Wireless video surveillance systems (VSS) are actually easier to install in your home than hard-wired systems. Wireless VSS transmits radio signals from your camera or transmitter to a receiver. The receiver will be connected to your TV or VCR (or whatever kind of monitoring equipment you buy) via a cable, but that's the only cable you'll have to use when you set up a wireless video surveillance system. You don't have to connect the transmitter and the receiver with wires.
Basic Components of a Wireless Video Surveillance System:
at least one camera/transmitter
power supply (typically 12-volt DC)
receiver and antenna
cable (to connect your receiver to your monitoring equipment)
optional additional monitor and VCR
A VCR is only a necessary component to a video surveillance system if you want to record the images being broadcast by your transmitter. Some homeowners will just broadcast the signal live to monitor instead of recording hours worth of footage.
Tools Needed to Install a Wireless Video Surveillance System:
a drill
a pencil for marking your drill spots
a screwdriver
a ladder
a small wrench for tightening cable ends
Before you start installing your VSS though, you'll want to make sure you thought through where to put your cameras and equipment. Draw a diagram of the area you want to cover whether it be indoors or outdoors. Figure out where you can put your cameras where they will be most effective. Remember to read the documentation that came with your cameras.
Wireless technology: the latest model to build video surveillance - video surveillance, technical articles - Security Industry
Video surveillance from the cable into the wireless access mode is an inevitable trend. With the increasing development of wireless technology, Wireless transmission Technology is increasingly being accepted by all walks of life. As a special-use wireless control methods have gradually been optimistic about the user. Its easy installation, flexibility, cost-effective advanced features make the industry more Monitoring System Use of wireless monitoring, establish monitoring points and monitoring center is the connection between. Wireless monitoring technology has been in modern communities, Traffic , Transportation, water conservancy, shipping, security, fire and other fields has been widely used.
Wireless video transmission to break the traditional coaxial and optical images Monitoring Subject to the adverse situation of the hardware connections, with more flexibility and convenience of wireless network based video surveillance system came into being. Wireless video transmission technology has the structure of the wireless mobile networks and protocols had a profound impact, but because of the limited wireless channel bandwidth, interference by many factors, but the video signal data volume, real-time requirements such problems. car key remote control
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Three major advantages of wireless transmission China car key duplicate
1, integrated, low cost, just a one-time investment, without trenching pipe, suitable for outdoor distance and has Decoration Good occasion; in many cases, users are often due to geographical conditions and work content of the restrictions, such as mountains, ports and open to other special geographic environment, on cable networks, cable transmission wiring works great inconvenience, with Cable The construction period will be very long, or even impossible to achieve. Then, using wireless monitoring can get rid of the shackles of cable, installed a short cycle, easy maintenance and expansion capability, the advantages of rapid cost recovery.
2, low maintenance cost, wireless monitoring and control is maintained by network provider maintenance, front-end devices are Plug and Play, maintenance-free system.
3, wireless monitoring and control system is a combination of wireless transmission technology, it can be in different locations on-site information in real time via wireless communication means to transmit to the wireless monitoring center. In the wireless monitoring system, real-time wireless monitoring and control center needs to be monitored by point of video information, and the video information must be continuous, clear. In the wireless monitoring point, commonly used Camera The situation in real time on-site collection, a video camera connected to the wireless transmission equipment, and through the radio waves to send data signals to the monitoring center.
Wireless video surveillance transmission technology
Reliable signal transmission channel purpose of the study is to make full use of channel bandwidth; and unreliable channel for transmission in the focus of the study is to make full use of bandwidth resources to achieve reliable transmission, that is fault-tolerant transmission technology. Discussed here in the wireless channel on the video transmission system, its main research is fault-tolerant transmission control. Fault-tolerant transmission control technology under its control method can be divided into three categories: namely, the forward error control, ARQ, and based on the feedback of the joint source and channel coding. Forward Error Control (ForwardErrorControl, FEC), including the channel error correction coding, interleaving packaging technology and optimized packet scheduling mechanism. ARQ techniques based on feedback information including the use of multi-frame reference picture selection mechanism (ReferencePictureSelection, RPS) mechanisms, hybrid ARQ (Hybrid, HARQ) feedback mechanisms and ARQ-based error tracking. As the ARQ-based fault-tolerant transmission control technology has excellent performance, so this highlights the ARQ transmission control-related technologies, and discuss the existing fault-tolerant video transmission system weaknesses.
Forward error control coding using forward error correction method to overcome channel errors. Fluctuations in the channel error probability of more severe cases (such as existing mobile channel), in order to obtain a certain transmission quality, forward error correction coding must be present to increase the estimated worst-case redundancy check bits, which will lead to waste of bandwidth resources. On the already limited bandwidth wireless channel is concerned, obviously can not meet the requirements. To this end, consider the ARQ and forward error control techniques combine, called HARQ technology. HARQ is divided into two types: I type HARQ, the sending side to have some forward error correction coding ability, when the receiver was detected, the first use of forward error correction coding to correct errors. If the error is corrected, then the sender sends a packet reception success of the current feedback information (ACK), the contrary is received failed to send a message (NACK). Sender if received ACK, then continue to send the next packet, otherwise, the re-issue of wrong packets. So I need a strong class of ARQ FEC, in applications where a lower error rate would result in waste of bandwidth resources, but the error rate in the environment can be better than other types of ARQ system throughput efficiency. Only the required class ARQ FEC error detection capability can have, according to error-correcting capability of channel coding theory known, it can play a role in saving bandwidth. When the receiver found in error, send a repeat request; the sending end only the error data transmission with error correction ability corresponding checksum. When the receiver received, if still not correct the error, then continue to send the retransmission request, the sender can choose to retransmit the data and the overall error check code, you can also choose to send a stronger ability to check error-correcting codes, specifically for different control strategies can be adjusted. View of the wireless channel error rate, with the feedback channel usually used for wireless transmission of HARQ-I. Figure 2 shows the use of HARQ-I of the wireless video transmission system, the figure dashed box represents a transmission error control of the process. According to the design principle of HARQ-I, the receiver found that error, the error corrected before the first (shown in the first layer of error screen), if not corrected and the current system to meet the delay constraints, then send the ACK request to let the sender re- outgoing wrong part of the data (second error screen). This retransmission can be repeated to correct data received by the receiver or retransmission delays within the system until the delay constraints. If the retransmission can not be correct even after the end of the packet, the receiver will use the error concealment techniques for error recovery (the third layer error screen). Can be seen, the basic idea of this mechanism is to make use of ARQ techniques mistakes to restore the error, so there will be named "best effort" ARQ mechanism (BestEffort ARQ, BEA, RQ).
As video signals have a strong correlation between time and space, and the encoder can not completely remove this correlation, so the decoder can use to restore the relevance of these residues in some quality video. Restore the quality also, and restored part of the texture and motion are closely related, in general, compared to the texture
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