4G wireless communication covers a large number of frequency bands and must be backward compatible with 3G/2G technology, which poses great design challenges for network devices and end-user devices. Therefore, related product developers have begun to simplify hardware configuration using software defined radio (SDR) technology. And to increase the flexibility to support various radio frequency bands to accelerate the development of multi-frequency multi-mode products.
Due to the popularity of mobile devices, end consumers often have multiple mobile devices at the same time, and these have become essential necessities for modern people. The increase of these devices has also caused users' demand for communication traffic to continuously increase to large traffic and large bandwidth. Therefore, wireless network communication will continue from 2G to 3G, and then to today's 4G extension, and the future 5G planning is also in progress. Expanded among countries.
Through such a trajectory, it can be found that in response to different network speed requirements, the network equipment providing services must be continuously developed and updated, and the explosive growth of data demand in recent years has also caused equipment development engineers to face time-lapse pressure. On the other hand, for operators providing communication services, the rapid network infrastructure is built at the same speed as a large number of users, which is also equivalent to good user experience and profits.
As early as the mid-1990s, software-defined radio (SDR) was developed in North America. At that time, it focused on 2G Air Interface, but due to technical factors, the business model of user-side equipment adopting SDR development is not Success, so the application of SDR on 3G base station equipment has become the development direction of this technology, so it continues to be paid more attention to the development of 4G base station.
Traditionally, building a radio system is not an easy task. Most of its designs use analog circuits and components such as antennas, oscillators, filters, signal amplifiers, signal modulation and demodulation transformers, and multitasking/demultiplexers. Wait. In addition, the design of the analog components not only causes the price to be expensive, but also the manufacturing cost cannot be lowered. It often requires engineers to constantly adjust and test in order to achieve a good operation mode. The wireless system thus designed does not provide the ability to adjust or reconfigure the device after the finished product is finished, so that once it needs to be modified or the system is updated internally, it must be redesigned and manufactured, which affects the design cost. Biggest reason.
The emergence of SDR is to provide a radio hardware solution that can be adjusted or reorganized, and can be set and configured by software, which can provide different network bandwidth and different according to different usage requirements and different radio frequency bands. The signal modulation and demodulation functions required by the wireless device are required.
The software radio concept proposed by Professor Joseph Mitola III in 1992 also hopes to eventually reach the equipment and systems in the system architecture of the software radio, and can dynamically adjust and set the radio on the system without offline. The signal processing module is equipped with various parameters to meet different needs. In the current development stage of the long-range evolution plan (LTE), it is also hoped that components with adjustable or reconfigurable capabilities will accelerate the development time of the equipment and improve the flexibility of the operators.
SDR RF front end is changing with each passing daySince the idea of ​​SDR has been proposed, related functions and applications have been continuously developed. Many manufacturers' products claim to have SDR function. Here, the main functional blocks are introduced.
The SDR of the small cell's RF front-end can be divided into two large architectures, a module that simulates RF signals, and a block that is processed by a baseband signal. At present, many manufacturers have introduced their own SDR module design, and provide a test environment for engineers to quickly use, increase the market share of their own chips, and also promote to open hardware and software forums, so that more people can actually The test is used, and the published information can also be used to understand the SDR design architecture and the situation on the Small Cell application.
Since the radio module integrated circuits of the RF front-end are evolving, the RF transceiver signal circuit composed of the early discrete components has been modularized since 2000, and can be used by small radio manufacturers who manufacture low-power output. Analog components such as analog/digital converters and signal modulation and demodulation transformers, as well as multitasking/demultiplexers, have been integrated and modularized, reducing the complexity of the lines used to fabricate front-end RF modules. a lot of. But to make multi-frequency multi-mode products, equipment vendors still use hardware-defined radio (HDR) (Figure 1), using multiple layers of hardware to achieve multi-frequency multi-mode system requirements.
Figure 1 Multi-frequency multi-mode hardware definition radio
When a small base station developer makes a multi-frequency multi-mode product, if the circuit of the separate RF transceiver signal chain modular scheme is used (Fig. 2), the production will still lead to lengthy product design time and high production cost. So there are vendors that have developed integrated RF transceivers that are expected to help developers simplify product design and reduce overall bill of materials (BOM) costs.
Figure 2 RF transceiver block consisting of separate components
Litz Wire Typical applications are: high frequency inductor, transformer, frequency converter, fuel cell, the horse, communication and IT equipment, ultrasound equipment, sonar equipment, televisions, radios, induction heating, etc.In 1911, New England became the first commercial manufacturer in the United States to produce the Leeds line.Since then, New England has remained the world leader in providing high-performance Leeds line products and solutions to customers around the world.It is also transliterated as the "litz line".
Litz Wire,Copper Litz Wire,Copper Transformer Litz Wire,High Temperature Litz Wire
YANGZHOU POSITIONING TECH CO., LTD , https://www.yzpstcc.com