Hybrid electric vehicles bring new challenges to power management The two main trends of "green" vehicles that enhance energy efficiency and reduce gas emissions, enhance protection and improve safety function levels are driving the development of a new generation of vehicles. Obviously, a car with a green design is not necessarily a hybrid electric vehicle (HEV). In fact, there are many traditional technologies that can make cars more in line with environmental protection requirements, help to improve fuel efficiency and reduce gas emissions, such as direct fuel injection, variable valve control, cylinder fuel economy, turbocharged engines, lubricated engines, etc. From the perspective of energy saving, we see "green cars" of different designs and styles. Some of them allow consumers to meet their needs with less budget. The start-stop function is an energy-saving function at a reasonable price. This function allows the internal combustion engine to automatically suspend operation when the car encounters a red light or is in a traffic jam. European OEMs have regarded this feature as a standard feature of their mainstream platforms. The additional cost of the entire start / stop function is only $ 300, but it can save 3% to 10% of fuel, and the effect is very significant. If the car is driving in a city with very heavy traffic, it can even save up to 25% of fuel. Since the start / stop function can be run on a standard 12V power network without expensive higher voltage systems or extra energy storage batteries required for light and full hybrid vehicles (HEV), this design becomes the main feature of this function Cost advantage. Of course, for many people, HEV is equivalent to the green car of the future, but we must note that HEV has many different designs in development, including a miniature with a pure start / stop function through an integrated starter AC engine (ISA) HEVs, full HEVs and plug-in HEVs that continue to increase the energy efficiency of pure electric driving have a wide variety of designs. Since the light, comprehensive and plug-in HEV requires high-voltage electronic systems between 600V and 1,200V, this makes the design more challenging. In order to provide sufficient electric engine power to electric engine vehicles, or to provide sufficient support for internal combustion engines, some large engine drives are required, and these large engines were only used in the industrial world before, and are now gradually entering automotive applications. In addition, it is necessary to integrate the electric power system and other new electronic systems into the new HEV vehicle architecture. The new electronic system includes a DC / DC converter that can realize energy transmission between 12V and high-voltage power grids, as well as many electronic drive systems such as air conditioning and power steering systems. This is a challenge for the automotive engineering and semiconductor fields, because people used to work in a 12V battery environment, but now they suddenly face the dangers caused by high-voltage electronics, so these dangerous electronic systems must be Safely isolate. In addition, HEV's high-voltage architecture also requires the deployment of additional peripheral systems and energy and battery management units. Therefore, we must develop reliable, advanced driver ICs and switches in the field of power management to meet the challenges of the automotive environment. Its efficiency and cost-effectiveness must ensure that the technology of the entire design concept is practical and feasible, and the price will not exceed the user's acceptable range. . IR's power management semiconductors can support all of the above requirements, but the main challenge facing HEV is the technology of the battery itself. Today, batteries including new lithium-ion batteries have technical limitations and shortcomings. For example, they can only walk a limited distance between two storages; long charging time; and the high cost of the battery, the huge Volume and weight. While global battery manufacturers strive to improve the electrochemical technology of the battery itself, we believe that through intelligent electronic battery management solutions, we can promote the continuous improvement of the battery to extend the life of the battery, provide better performance, and reduce costs, volume and weight. Green design and HEV bring new challenges to power management in the automotive industry. International Rectifier (IR) has an absolute advantage in this regard. IR has a long experience in industrial engine drive power management, making us a unique automotive semiconductor supplier. IR can provide high voltage power switches such as high voltage driver ICs and IGBTs. Today, we have a first-class engine-driven product camp, and we plan to launch more than 200 new automotive products specifically designed for harsh automotive environments within the next 12 months. Take our engine control IC as an example. This IC has integrated various safety functions to prevent catastrophic failure in the event of a short circuit in the power engine. In addition, the latest DirectFET product line for bondless automobiles not only brings very low on-resistance to the design of DC / DC converters and battery management systems, but also eliminates the need for bonding wires, which enables very fast Under switching conditions, the parasitic inductance can basically reach zero, while having first-class EMI performance. IR's automotive business unit has five product lines, including high-voltage driver ICs, smart power ICs, smart switches, MOSFETs, and high-voltage IGBT switches for low, medium, and up to 1,200V. IR can provide a comprehensive chipset solution for almost all power management applications found in a modern HEV. First, Wireless Router Wifi 5 Wireless Router,5Gz Wifi Router,Wi-Fi Routers For The Home,Lte Modem Router Shenzhen MovingComm Technology Co., Ltd. , https://www.mcrouters.com
Dr. Henning M. Hauenstein, Vice President and General Manager, Automotive Products, International Rectifier
So what is a wireless router?
Wireless router, according to the definition of Baidu Encyclopedia: Wireless router is used for users to access the Internet, with wireless coverage of the router.
A wireless router can be thought of as a repeater that forwards the broadband network signal from the wall of your home through an antenna to nearby wireless network devices (laptops, Wifi-enabled phones, tablets, and all Wifi-enabled devices).
The popular wireless routers in the market generally support four access methods: dedicated xdsl/cable, dynamic xdsl, pptp, and generally can only support 15 to 20 devices online at the same time. It also has some other network management functions, such as dhcp service, nat firewall, mac address filtering, dynamic domain name and so on. The signal range of the general wireless router is 50 meters radius, and the signal range of some wireless routers has reached 300 meters radius.
The name of wireless router can be separated out of two keywords: wireless and routing.
Understand the technical principle behind these two words, you understand the wireless router.
Wireless is also what we often call Wi-Fi. Wireless routers can convert home broadband from wired to wireless signals, and all devices can happily surf the Internet as long as they connect to their own Wi-Fi. In addition, these devices also form a wireless local area network, where local data is exchanged at high speed and is not limited by the bandwidth of home broadband.
For example, many people have smart speakers in their homes that can be used to control various smart appliances. When you say small X small X, turn on the TV, the speaker actually finds the TV through the LAN and sends instructions, and does not need to connect to the Internet; And if you let it broadcast news, you have to get data through the Internet.
The Local Area Network we talked about earlier, also known as the Intranet, is represented by the Local Area Network (LAN) on the router, so the Wi-Fi signal is also called WLAN(Wireless LAN); The Internet we want to access, also known as the extranet, is represented on the router by the WAN(Wide Area Network).
On the Intranet, the IP address of each device is different, which is called a private address. All devices on the Internet share the same public address, which is assigned by broadband operators such as China Telecom Unicom.
The router is the bridge between the Intranet and the external network. The above mentioned IP address translation, packet forwarding, is the router routing function. In other words, the router is the hub of the home network, and the data of all the devices must be forwarded through it to access each other or reach the external network, which means that one husband is the key and ten thousand men are not open, so the comprehensive router is also called "home gateway".
Second, the demand for wireless routers
I do not know if there is a sudden WIFI break when you play games at home, and a stable router is crucial at this time. However, it is important to note that your WIFI frequently dropped may not be a problem with the router, it may also be a problem with the carrier network. (Router means I don't back this pot)
In fact, for most people, there are two basic requirements for wireless routers
Stable and do not drop
Fast Internet and easy setup
Some people will have some advanced needs:
There are some features, USB interface, can be external U disk or hard disk, can achieve simple nas functions, QOS, etc., to advertising and so on
Mesh networking, when the house area is large, multiple routers can be used for Mesh networking
How to choose a wireless router
The wireless router market is in the transition stage from WiFi 5 to WiFi 6, if you want to buy the first choice is definitely WiFi 6 wireless router, which is the future trend.
The speed of WiFi 6 is nearly 40% higher than the previous generation 802.11ac, and the highest connection speed can even reach 9.6Gbps, while the highest speed of 802.11ac is only 6.93Gbp. More importantly, unlike 802.11ac, which only covers the 5GHz band, WiFi 6 covers 2.4GHz and 5GHz. Although the 5GHz band has less interference, it has weak wall penetration ability, and the 2.4GHz band has strong wall penetration ability, which takes into account each other.
So why choose a WIFI6 router?
Compared with the previous generation of 802.11ac WiFi 5, the maximum transmission rate of WiFi 6 in the 5Ghz band has been increased from 3.5Gbps to 9.6Gbps, and the theoretical speed has been increased by nearly 3 times. WiFi 6's 5Ghz single-stream 80Mhz bandwidth can reach theoretical speeds of up to 1201Mbps and 160Mhz bandwidth of up to 2402Mbps.
The band supports 2.4Ghz and 5Ghz.
In terms of modulation mode, WiFi6 supports 1024-QAM, which is higher than the 256-QAM of WiFi 5, and the data capacity is higher. Some high-end WiFi 6 routers support 4096-QAM.
WiFi6 supports MU-MIMO (multi-user multiple-input multiple-output) technology, and supports both upstream and downstream MU-MIMO, with a maximum support of 8T×8R MU-MIMO. The speed is greatly improved. High concurrency, WiFi6 5GHz band, terminal connections up to 128! 5 times that of WiFi5. Effectively solve the Internet needs of multi-person networking and smart home;
WiFi6 adopts OFDMA (orthogonal frequency division multiple access) technology. After using OFDM to parent the channel, the transmission technology of transmitting data is loaded on the subcarrier, allowing different users to share the same channel, allowing more devices to access, with shorter response time and lower delay.
Low latency, WiFi6 time delay can be as low as 10ms, compared to WiFi5 30ms delay, only 1/3. This performance refresh is extremely friendly to game lovers;
If WiFi6 (wireless router) devices need to be certified by the WiFi Alliance, they must use the WPA 3 security protocol, which is more secure.
The WiFi6 wireless router is backward compatible with WiFi5 and WiFi4 terminals.
Fourth, the misunderstanding of purchasing routers
Is the through-wall router really through-wall?
Mistake; The country has strict limits on the transmission power of the wireless router antenna, if you have a lot of rooms in your home, and there are many walls between them, even if you buy an expensive wireless router, you can not do one to cover all the room signals. If the signal is not good, you can consider multiple wireless router Mesh networking.
Does a wireless router have a stronger signal with more antennas?
More antennas just to match the X*X MIMO mode, the more antennas, the more channels, can only ensure that the network is more stable, the impact on the signal is little, the strength of the signal is only related to the wireless transmission power. The wireless transmission power of the country has a standard.