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The detailed difference between 4G industrial router...   4G industrial router and 4G DTU both realize the wireless network data transmission function, and the differences between them are mainly from the use method, appearance interface and application environment, etc. Today, we will introduce some differences between 4G router and 4G DTU.   Different methods...

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Application analysis of iot sensing technology   The Internet of things (iot) is widely used in the integration of networks through intelligent perception, recognition technology, pervasive computing and other communication perception technologies. The iot is understood as "Internet connected by things". The Internet of things (iot) connects all objects with...

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What is a single/dual frequency wireless 4G router 1. Introduction to "single frequency" router The single-frequency router only works in the 2.4ghz band, which is generally supported by wireless terminals. However, the 2.4ghz band has large interference, which may affect the wireless rate and stability.   2. Introduction to "dual-frequency" router Dual-frequency...

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Wireless communication DTU features Data Transfer unit (DTU) is a wireless terminal device specially used to convert serial Data into IP Data or convert IP Data into serial Data for transmission through wireless communication network.   DTU advantages: Rapid and flexible network, short construction cycle, low cost; Wide network coverage; Good...

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The advantage of using wireless data transmission module... Data transmission can be simply divided into two major types: wired (including the installation of optical cables, cables or leased telecommunication lines) and wireless (including the establishment of dedicated wireless data transmission system or the borrowing of CDPD, GSM, CDMA and other public network information platforms).     In...

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TDD LTE and FDD LTE

Category : 技术相关

As we know, the LTE mainly covers two types, which are TDD and FDD.  Let’s talk something about TDD LTE and FDD LTE’s Advantages / disadvantages of for cellular communications.

There are a number of the advantages and disadvantages of TDD and FDD that are of particular interest to mobile or cellular telecommunications operators. These are naturally reflected into LTE.

COMPARISON OF TDD LTE AND FDD LTE DUPLEX FORMATS
PARAMETER TDD LTE FDD LTE
Channel reciprocity Channel propagation is the same in both directions which enables transmit and receive to use on set of parameters Channel characteristics different in both directions as a result of the use of different frequencies
Paired spectrum Does not require paired spectrum as both transmit and receive occur on the same channel Requires paired spectrum with sufficient frequency separation to allow simultaneous transmission and reception
Hardware cost Lower cost as no diplexer is needed to isolate the transmitter and receiver. As cost of the UEs is of major importance because of the vast numbers that are produced, this is a key aspect. Diplexer is needed and cost is higher.
UL / DL asymmetry It is possible to dynamically change the UL and DL capacity ratio to match demand UL / DL capacity determined by frequency allocation set out by the regulatory authorities. It is therefore not possible to make dynamic changes to match capacity. Regulatory changes would normally be required and capacity is normally allocated so that it is the same in either direction.
Guard period / guard band Guard period required to ensure uplink and downlink transmissions do not clash. Large guard period will limit capacity. Larger guard period normally required if distances are increased to accommodate larger propagation times. Guard band required to provide sufficient isolation between uplink and downlink. Large guard band does not impact capacity.
Cross slot interference Base stations need to be synchronised with respect to the uplink and downlink transmission times. If neighbouring base stations use different uplink and downlink assignments and share the same channel, then interference may occur between cells. Not applicable
Discontinuous transmission Discontinuous transmission is required to allow both uplink and downlink transmissions. This can degrade the performance of the RF power amplifier in the transmitter. Continuous transmission is required.

 

Advantages and Disadvantages of 4G WIRELESS TECNOLOGY

Category : 技术相关

Today is the day of high data requirement in internet. In most field the wireless system is very widely used. Currently a number of technologies like 1G, 2G, 2.5G, 3G, 3.5G etc.  A new technology is introduced which is called as 4G technology.

Fourth generation wireless system is a packet switched wireless system with wide area coverage and high throughput. It is designed to be cost effective and to provide high spectral efficiency. Data rate of 20mbps is employed. Mobile speed will be up to 200km/hr. The high performance is achieved by the use of long term channel in both time termchannel in both time and frequency, scheduling among users and smart antennas combined with adaptive modulation and power control. Frequency band is 2-8 GHz. it gives the ability for world wide roaming to access cell anywhere.It uses OFDM (ortogonal frequency divisional multiplexing) and Ultra Wide Radio Band(UWB), and Millimeter wireless and smart antenna.4G uses a multi network functional device software which is very helpful for multiple user.

Advantages
-support for interactive multimedia, voice, streaming video, Internet, and other broadband services -IP based mobile system-High speed, high capacity, and low cost per bit. -global access, service portability, and scalable mobile services -Seamless switching and a variety of Quality of

-Better spectral efficiency. Service driven services.
- Better scheduling and call admission control techniques

Disadvantages
-Expensive and hard to implement
-bettery usage is more
-needs complex hardware

Conclusion
There is a need for next generation of wireless technology i.e. 4G which will be a platform for seamless technology providing widespread coverage, band width and power consumption with higher data rates (100Mbps, 150Mbps and 300Mbps, future will update to 1000Mbps, etc.).