April 28, 2024

Three common transmission methods for wireless video surveillance

How to choose the wireless monitoring system that is suitable for your own use depends mainly on the actual needs and what kind of transmission method you choose. The current mainstream wireless video surveillance has 3G / 4G mobile video surveillance, WLAN (wireless local area network) wireless video surveillance, microwave (analog microwave) wireless video surveillance, COFDM wireless video monitoring, wireless monitoring satellite.

1, 3G transmission 2G transmission mode mainly includes CDMA, GSM two modes. The two modes have lower costs, have larger coverage, and have faster transmission speeds, among which the CDMA theoretical value transmission rate is 153.6 Kbps, and can reach 60~80 Kbps in practical use, and therefore cannot be used in wireless monitoring. Less favored by vendors. The GSM-based GPRS, although the coverage rate is higher than CDMA, but the transmission rate is slightly slower, so it is still in use. The 3G transmission methods mainly include 3G technology access methods for mobile (TD-SCDMA), telecom (CDMA2000EVDO) and China Unicom (WCDMA) operators. Since 2009, they have been vigorously promoted by various operators, and many monitoring manufacturers have R & D related products in this area. The 3G advantage that the projecting speed download capability, over a transmission rate can reach values ​​of 3Kbps ~ 1G, 4G devices currently on the market has also been widely used in 3G superior basis.

Advantages: Large range of mobile monitoring Disadvantages: Low bandwidth, monthly rental fees for the industry: Suitable for public transport video surveillance, real-time monitoring of long-distance bus, bankroll management and video surveillance, ship video surveillance, military training mobile command, reporter tracking interview, off-road Video monitoring system for event monitoring, event security management, traffic capture and other scenarios.

2. COFDM Transmission COFDM, the abbreviation of Orthogonal Frequency Division Multiplexing, is the world's most recent and most promising modulation technology. Its practical value lies in supporting the application of breakthrough line-of-sight restrictions. It is a technology that is fully utilized in the radio spectrum resources. It can have good immunity to noise and interference. Diffracting and penetrating obstructions are technologies of COFDM. core. The basic principle is to transfer high-speed data streams through serial-to-parallel conversion to several sub-channels with lower transmission rates.

Advantages: Small-scale mobile monitoring, non-line-of-sight, diffraction Difficulties: Frequency applications need to be applied, low bandwidth, high prices for the industry: mobile emergency transmission applications. Applied to *, fire, *, civil air defense emergency, * law enforcement, environmental protection monitoring, fire emergency, water conservancy flood control, power rescue, railway rescue, maritime law enforcement, maritime surveillance inspection, customs frontier defense, dock monitoring, forest fire prevention, oil field anti-theft, military reconnaissance In other fields, it is suitable for real-time mobile transmission and monitoring in various complex environments such as urban areas, seas, and mountains.

3. The concept of WLAN (Wireless Local Area Network) and general traditional Ethernet (Ethernet) is not much different. It is only the transformation of the line transmission part of Ethernet (Ordinary NIC - Category 5 - Ordinary HUB). Into a wireless transmission form. It can also be said to be digital microwave for two-way communication. The line-of-sight wireless bridge is designed for long-distance point-to-point interconnection between wireless LANs. It is an implementation of LAN interconnect devices store and forward link layer for long-distance between the fixed device and the other a fixed number of digital devices (up to 20km), high bandwidth (up to 11/54/108/150 / 300Mbps) wireless networking. It is suitable for the temporary networking of long-distance high-speed networking and field operations in cities.

Advantages: in the free working frequency (2.4G / 5.8G), higher bandwidth (11/54/108/150 / 300Mbps), distance (30-50km), flexible networking (supports point-to-multipoint, Relay, MESH, and cheaper prices Disadvantages: Fixed wireless transmission is suitable for the industry: the most effective and most economical network video monitoring system.

In-mould labelling (IML) was initially designed for blow molding, though developments using injection molding or thermoforming with reel-fed systems have increased the efficiency of the labelling process. The original concept involves coating the reverse side of the label with a heat seal layer, followed by a substrate material in which heat resistant ink is applied to. A heat resistant coating of lacquer is then applied .In-mould labelling is a popular method of decorating injection molded parts for consumer electronics and for plastic bottles. Notebook computer and cellphone manufacturers are adopting IML technology for greater wear resistance than spray painting or pad-printing. IML can provide greater decorating options than other methods. Multi-color screen printed and offset lithography printed graphics are used to produce products with higher quality graphics than available with other decorating methods. What is IML?The term "in mould labelling" is directly derived from the technique: a preprinted polypropylene (PP) label is placed in a mould. This mould has the shape of the end product, e.g. the shape of a butter tub.Then the molten PP is added to the mould. It fuses with the label, and while curing, takes the shape of the mould. Result: label and packaging become one.In mould labelling can be done in the following production processes:

Injection moulding  Blow moulding Thermoforming   In mould labelling offers several major advantages:   Maximum print quality,Strong and hygienic, Shorter production time and lower production costs,  Environmentally-friendly,Wide range of look & feel options,Quick design changeovers.    

Sumsung Case  Iml Plastic Mould 40  Iml Plastic Mould 10  Iml Plastic Mould 34  Iml Plastic Mould 44  Iml Plastic Mould

IML/IMD Moulding Parts

Imd Moulding Parts,Iml Container Cover,Waterproof Household Cover Iml Mould,Mould In Labeling Top Bottom Cover

Topwell Spring Development Ltd. , http://www.topwelldesign.com