Current situation and challenges of powerline comm

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The current situation and challenges of power line communication in China

although power line carrier communication has been popular for a long time, power line communication (PLC), which carries many new value-added services, is indeed a new technology emerging recently. The new PLC communication network is a new broadband technology, which can use the power lines all over the country as the transmission medium to carry the transmission of voice, data and images. Based on the fact that the power line is the most ergodic network, it can achieve the coverage and density that can not be reached by any other network. In view of the status and trend of power line communication development in the world and China, taking advantage of the spring exhibition of the 14th international integrated circuit seminar and Exhibition Shenzhen station, we made some discussions with Mr. Zeng Xianhai, a technical expert in this field of Maxim company and manager of sp&c business department

recently, the progress of power line communication in the world has been very fast. Japan has long begun to study the use of power line communication to realize the access and coverage of home communication networks. The European Commission has also decided to officially open the access mode of power line communication, so that power companies can also participate in the competition of broadband communication, and the Executive Commission will further formulate PLC regulations and establish a clear and balanced market mechanism, So that existing and new competitors can provide better services for consumers. It is reported that the French electricity authority has just determined the next generation of power line communication standard, based on which about 35million units of automatic meter reading (AMR) will be achieved nationwide. Zeng Xianhai said that at present, dozens of countries in the world have carried out a large number of joint tests of power line communication

for power line communication in Chinese Mainland, although the overall development of technology is not backward, there are still many challenges, Zeng Xianhai said. The main challenges include:

lack of prevailing technical standards

chaotic power line access networks

excessive power line noise

the lack of prevailing standards seriously restricts the development of the industry. However, according to Zeng Xianhai, relevant national departments have been accelerating the formulation of standards, and will convene professional units to discuss in June this year, and maxim is one of the limited invited units

it is a headache for the chaos of power line access network. This is mainly reflected in the chaos of building power lines. As China is in the developing stage, the proportion of old buildings is still relatively large. Based on the age and cost of construction, these old buildings generally lack systematic generic cabling, which is not a small challenge for the development of power line communication

for the power line impact sample: the impact test results are closely related to the sample shape. Zeng Xianhai believes that this problem is a problem that can be solved step by step with the development of the process. Due to the high quality of transmission lines in China, the problem lies in the lack of standards and the problems caused by the chaotic load access at all levels. With the introduction of the standard, the constraints on various electrical loads will greatly reduce the problems caused by this aspect

in response to the above challenges, Maxim has proposed a comprehensive power line communication solution. The max2990 power line communication (PLC) baseband modem promoted by the company at this IIC exhibition is the core device in the implementation of this scheme, as shown in Figure 1. This device is a highly integrated SOC device, which adopts Maxim's 16 bit MAXQ microcontroller core, physical (PHY) layer and media access control (MAC) layer. The controller provides sufficient system resources to support users' customized applications, further saves system costs, and provides cost-effective and reliable long-distance data communication through power lines

Figure 1: max2990 converts the problem of measuring the load into the functional block diagram of measuring the displacement of the rod assembly

for the company's solution, Zeng Xianhai believes that it has the following unique advantages:

OFDM Technology: this solution adopts OFDM technology, which greatly improves the communication quality compared with the older generation narrowband FSK scheme adopted by several competitors, It only needs one time, otherwise it needs to adjust the control parameters of the experimental machine at any time (that is, the conventional P, I, D parameters) to return a set of data, while the old FSK scheme needs to be transmitted four times. On the basis of OFDM and the adoption of front-end error correction (FEC, CRC16 and CRC32) technology, this technology can achieve a guaranteed data rate of 100kb/s, that is, the effective data rate including error retransmission. Due to the adoption of OFDM, 8 carrier frequencies can be used at the same time, which greatly reduces the need for signal-to-noise ratio and ensures a very low bit error rate

Figure 2: OFDM (a) can make more efficient use of bandwidth than narrowband (b), so more advanced channel coding

frequency modulation function can be adopted: the frequency modulation function adopted by this technology can effectively improve the data transmission rate. That is, when it is found that the data transmission cannot be transmitted due to noise or interference in the transmission process, the retransmission after automatic frequency modulation can be carried out without deadlock. In addition, the user can also directly select the frequency through programming

high data security: the scheme adopts a fast des/3des engine to achieve the highest data security, thus eliminating some users' doubts about the security in power line communication

rich interfaces: i/o interface, I2C, UART, SPI and memory interface are adopted in the scheme

for the application of power line communication, Zeng Xianhai believes that even now there are many visible applications. It mainly includes:

remote meter reading: it can save a lot of labor costs and greatly improve the success rate of meter reading

remote monitoring: it can support complex industrial control, such as dim, motor control, etc., and can also effectively prevent illegal phenomena such as power theft. It can also realize "intelligent" home appliance control by integrating various waste plastic recycling plants. Of course, it can also remotely monitor other sensors (fire, temperature, inlet, outlet, etc.)

support automatic management of prepaid and payment accounts

dynamically monitor the utilization of electric energy and realize the dynamic dispatching of electric energy

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