免费国产直接看片av

<li id="dokzq"></li>
  • <center id="dokzq"><progress id="dokzq"></progress></center><sub id="dokzq"></sub><track id="dokzq"><center id="dokzq"></center></track>
  • <track id="dokzq"><li id="dokzq"></li></track>
  • <tbody id="dokzq"></tbody><track id="dokzq"><li id="dokzq"></li></track>
  • <track id="dokzq"></track>
  • <tbody id="dokzq"></tbody>

    Microwave solves fiber shortage problem at LTE backhaul site

    On December 4, 2013, the Ministry of Industry and Information Technology officially issued TD-LTE standard 4G licenses to China Mobile, China Telecom and China Unicom. China has officially entered the 4G network rapid growth period. The issuance of 4G licenses is a great opportunity for Chinese operators, but it also faces challenges: LTE base stations have small coverage, deployment density is much higher than GSM base stations and 3G base stations, and LTE construction will face a large number of new site requirements. However, some new sites have a shortage of fiber resources, and new fiber is laid, which has high cost and long cycle, which cannot meet the needs of LTE rapid station construction and affects LTE network coverage. In the face of challenges, domestic operators began to use microwave backhaul to solve the problem of lack of fiber resources. Microwave transmission does not require fiber-optic cable connection, and can quickly establish base station backhaul connection, cooperate with existing network fiber network, realize rapid deployment of new sites, and help LTE network construction. .

    In other parts of the world, such as Europe, Southeast Asia and other countries, these countries are restricted by the privatization of property rights, and the end fiber resources are extremely scarce. Microwaves have become the 3G/LTE mobile backhaul in such regions due to their wireless transmission and rapid deployment. The mainstream solution. Microwave is widely used in the world, and its products and solutions are also very mature. Mainstream telecom equipment suppliers (such as Huawei, Ericsson, ALU, NEC, etc.) provide mature microwave products, and the industry chain is quite perfect and mature. At present, the global microwave market space is about 5 billion US dollars, of which 83% of microwave equipment is used for mobile backhaul.

    Microwave evolution to packetization and large bandwidth

    Two characteristics of LTE base station service backhaul: 1. Uplink interface packetization; 2. Backhaul bandwidth demand is large.

    As a supporting wireless backhaul solution, microwave technology is also evolving. Packet microwave was introduced in 2008. It is a microwave that supports packet switching and dynamically adjusts the transmission bandwidth. It can implement MPLS/PWE3-based mobile backhaul solution, suitable for 3G/LTE scenarios. Compared to traditional TDM microwaves, which provide more bandwidth, packet microwaves can achieve single carrier frequency up to Gbps, providing advanced packet technologies such as MPLS/MPLS-TP and 1588v2 clock synchronization. Moreover, it has the same reliability as the TDM microwave, and can achieve similar service operation and maintenance capabilities with the SDH network, providing graphical network management, automatic protection switching, and real-time and accurate monitoring of alarms and performance.

    The current packet microwave technology is still moving forward, and more and more new features and technologies are emerging. At the 2013 Barcelona Communication Exhibition, the second-generation E-BAND and V-BAND new band packet microwave technology was launched. Among them, the second-generation E-BAND is the first to support large bandwidth (single carrier frequency 2.5Gbps), high spectrum utilization (1Gbps throughput only needs 250MHz spectrum), strong packet capability, high reliability and easy maintenance, etc. Favor. V-BAND products for free frequency bands are small, simple, low-key and environmentally friendly, suitable for street, building and other occasions. In particular, the unique smart antenna used by V-BAND can realize automatic alignment of the system, which greatly simplifies the installation method of the traditional antenna and attracts the attention of many operators at the exhibition.

    Packet microwave can effectively carry LTE services

    Compared with 3G networks, LTE networks have higher requirements on bearer networks, including large bandwidth, large network management, high QoS guarantee, high network reliability, and accurate clock synchronization. The packet microwave can fully meet these requirements of LTE bearer:

    Large bandwidth: With its 1024QAM high modulation mode, frame header compression, and air interface physical link aggregation, packet microwave can achieve ultra-large bandwidth of single carrier frequency Gbps, fully meeting the access and bearer requirements of LTE large bandwidth services.

    High network reliability: The 3GPP protocol imposes strict requirements on the delay and availability of LTE services. Packet microwave supports multiple carrier-class protection technologies based on MPLS/MPLS-TP, making packet services connection-oriented and achieving the same score as SDH. Layer management to ensure reliable business.

    High-quality service transmission: Packet microwave supports H-QoS, which makes QoS control more precise. Different customer services can have different priorities. Different priority guarantees can also be performed within the same customer service, thus effectively ensuring high-priority services and truly achieving high Quality business delivery.

    High-precision time synchronization: 1588v2 can fully meet the frequency and phase synchronization requirements of TD-LTE, reducing installation and maintenance costs.

    E2E network management: The common network management of packet microwave and packet optical equipment can realize the E2E pull-through of the service, protection, management and clock of microwave and packet optical equipment, effectively cooperate with packet optical equipment, and accelerate the pace of LTE network construction.

    Simple and fast deployment: The all-outdoor solution for packetized microwave equipment eliminates the need for a computer room, and is quick and easy to install and deploy, meeting the needs of LTE-intensive miniaturization and rapid deployment.

    Application of Packet Microwave in LTE Backhaul Network

    The packet microwave can be regarded as the wireless extension of the optical fiber, which mainly solves the problem of insufficient fiber in some scenarios, and quickly realizes service backhaul and improves network reliability. With the advent of the LTE era, packet microwaves have three main application scenarios as LTE mobile backhaul:

    End LTE service backhaul and integrated access for large customer services: If the fiber resources of the new site are unreachable, packet microwaves can be used to quickly access the services and then transmit to the fiber nodes. At the same time, packet microwaves can support multiple services. Customer business comprehensive bearer. The packet microwave can be seamlessly connected to the existing network packet optical device, and the network side adopts a unified NNI interface to implement end-to-end service distribution and management.

    Cooperate with packet optical equipment to form a ring-filled network: The accelerated construction of LTE consumes a large amount of resources for accessing optical fibers. Only 60% of the network access networks at the end of the network are expected to be optical fiber loops. If the fiber fails, the base station service on the single chain will be dropped, which has a huge impact. However, if the fiber is to be laid again, the cycle is long and the capital construction cost is high, which cannot improve the network reliability in a short period of time. The packet-based microwave can be seamlessly connected to the optical network of the existing network to form a ring network solution. The service ring network protection is configured to improve network reliability.

    Disaster recovery backup and emergency rescue: Packet microwave construction is flexible and fast. It can establish independent disaster recovery backup links between important network nodes, especially in natural disasters, to ensure permanent connection of important nodes. . In the event of a disaster, packet microwaves can be quickly built to achieve emergency communications.

    Concluding remark

    As one of the mainstream solutions for mobile backhaul, microwave is widely used for its fast construction and small investment. 70% of mobile base stations in the world use microwave backhaul, and nearly tens of millions of hops are running on the live network. According to the latest report in the third quarter of 2013, Dell's authoritative analyst Dell'oro showed that Huawei's growth in the microwave field was rapid. In the fourth quarter (Q12~3Q13), Huawei's global microwave market share was 22.4%, ranking first.

    With the issuance of 4G licenses in China, domestic LTE construction will enter a period of rapid growth. Packet microwaves, as a powerful complement to optical fiber, will become an accelerator for LTE backhaul network construction, helping operators to quickly establish high-quality 4G networks and enhance end-users. Experience and win market opportunities.

    A good laminate structure can control the characteristic impedance of the printed circuit board, and the traces can form an easily controllable and predictable transmission line structure called an impedance plate. The characteristic impedance of the conductor on the printed circuit board is an important indicator of the circuit design. Especially in the PCB design of the high frequency circuit, it must be considered whether the characteristic impedance of the wire and the characteristic impedance required by the device or signal are consistent and match.

    Impedance Control PCB

    Impedance Control In Pcb,Impedance In Pcb,Control Impedance Board,Industry Control Circuit Board

    Chuangying Electronics Co.,Ltd , https://www.cwpcb.com

    免费国产直接看片av
    <li id="dokzq"></li>
  • <center id="dokzq"><progress id="dokzq"></progress></center><sub id="dokzq"></sub><track id="dokzq"><center id="dokzq"></center></track>
  • <track id="dokzq"><li id="dokzq"></li></track>
  • <tbody id="dokzq"></tbody><track id="dokzq"><li id="dokzq"></li></track>
  • <track id="dokzq"></track>
  • <tbody id="dokzq"></tbody>