Wireless communication technology and PLC

PLC power line carrier communication is a communication method that uses power line to transmit data signals. Because power line is used as communication carrier, it provides great convenience for network deployment. Nowadays, the technology is becoming more and more perfect, and the transmission speed and distance are greatly improved.

The most common application scenario of PLC is smart grid. Because the line does not need to be reconstructed and the deployment cost is low, many national networks will use programmable controllers to realize power meter reading. In addition, there are Internet of things scenarios such as home automation and smart home, such as electric cat. Programmable controllers are divided into narrowband and broadband. The working frequency and data transmission speed of the programmable controller are low, but the transmission distance can be longer. On the contrary, the broadband programmable controller is only suitable for short-range applications, but it can still be transmitted remotely through the programmable controller.

Although limited by the sending power, PLC is too sensitive to interference, there are often a variety of electrical equipment on low-voltage power lines, which will produce different noise and impedance on power lines. Moreover, in order to ensure the transmission quality, PLC does not pursue long-distance transmission. In order to solve these limitations, in addition to large foreign manufacturers such as Qualcomm and Broadcom, many domestic manufacturers have developed their own PLC chips and modules to seek innovative breakthroughs in the PLC market.

Huawei Hisilicon

Hi3921sv100 is an integrated high-speed / low-speed multimode PLC modem and high-performance application processing core chip of Huawei Hisilicon. It implements the iee1901.1 standard subset on the physical layer, as long as it is the same subset. Interconnection can be realized. The CPU of the chip adopts Cortex-M3 processor with 200MHz working frequency and embedded 256Kb SRAM content.

Huawei claims that the chip can quickly form a PLC IOT network, and its strong anti-interference ability has become the best choice for smart home applications. In addition, the chip supports open liteos system and a variety of encryption algorithms. Developers can also connect and debug with various external devices through rich external interfaces.

Neusoft carrier

Since 1996, Neusoft carrier has been studying PLC technology and successively launched the first to sixth generation communication chips. At present, the cumulative sales of PLC chips has reached 300 million, and the PLC schemes running on the Internet have exceeded 100 million.

Neusoft carrier ssc1667 chip is an HPLC high-speed carrier power line carrier communication chip, which adopts 40nm process and integrates ARM processor and 1mbsram. The communication frequency band of ssc1667 is 0.7mhz to 12Mhz, and the communication speed can be up to 6Mbps.

According to official data, the chip supports the new national network interconnection standard and the old national network interconnection standard, and supports four band six mode switching. In addition, the chip also supports wire online upgrade, and adopts concurrent reading mechanism to improve the work efficiency of meter reading application.

Neusoft carrier said that in terms of meter reading efficiency and communication stability, especially the success rate of one-time meter reading and real-time communication ability, the narrowband carrier product has been greatly improved. It is not only suitable for the extended application of power grid meter reading and smart grid, but also can be used as a high-speed and reliable smart home application solution.

Dingxin communication

Dingxin communication is a high-tech enterprise focusing on PLC technology and bus communication technology. Its main terminal products are applied to the electrical information acquisition system of the National Smart Grid. While expanding the field of low-voltage power consumption, Dingxin communication also continues to carry out the development of medium voltage carrier, distribution network automation and 10kV charging station technology

Tcc091 and tcrs091 are broadband programmable controller chips independently developed and produced by Dingxin, integrating analog front-end, baseband modulation and demodulation, digital signal processing and CPU core. The chip adopts lattice core 28nm slpcmos process, which improves the performance by 60%, reduces the switching power consumption by 40%, and reduces the standby power consumption by 50%.

Tcc091 and tcrs091 also integrate the fifth generation simplified and efficient MCU + dspzspnano architecture to facilitate developers to transplant and optimize code while balancing performance, power consumption and area.

Cloud semiconductor

As a domestic CPU / MCU chip design company, Shanghai Yunjian Semiconductor Technology Co., Ltd. is committed to the design of independent CPU core and the research and development of SOC chip and system products based on independent CPU core. The company's main HPLC products are cr600 series and cr700 series, both of which are 32-bit PLC chips.

The carrier bandwidth of cr600 and cr700 is 2 ~ 28MHz, and the maximum transmission speed of physical layer is 240mbps. The transmission distance of the power line can be up to 10km through the maximum 10 level relay. Cr600 has built-in Cortex-M0 core with main frequency of 125MHz and SRAM of 256Kb. Cr700 has built-in ARM9 CPU, which is easy to run complex movie system and protocol stack.

At present, the largest market for programmable controllers is still the bidding of electricity meters and electrical information acquisition equipment of the State Grid. In addition to programmable controllers, these devices also integrate wireless technologies such as 4G, Nb Internet of things and private networks. As a wired technology, programmable controller can well cover the blind spot of wireless network.

For grid users, smart meters replace traditional mechanical and electronic meters. They can pay fees and see the use of electricity without going out. In the smart home market, wireless communication technology has developed rapidly, and the home scene can not give full play to the advantages of PLC wired transmission and transmission distance.

The one machine and two networks mentioned in Huawei's whole house intelligent scheme may be the best configuration scheme in the home market, which realizes central control through modular home intelligent host. Wi-fi6 + network is responsible for high-speed full coverage, while PLC whole house network focuses on stability and reliability. However, the key to this scheme lies in the system ecology of Hongmeng. Otherwise, even if the number of smart devices in each family promotes the networking requirements, different communication standards between devices will bring a split smart home experience.