qam antenna

Wireless networks have become the preferred network access solution for families and small and medium-sized enterprises, and some problems have emerged. Due to the large area of some houses, the structure of the residential buildings is changeable, and there are many obstacles, the signal attenuation of the wireless network is great, resulting in incomplete wireless coverage, weak wireless signal strength and low wireless speed in some areas, there are even wireless blind spots and other situati

online.SIM300 Module appearance The SIM300 is a three-band Gsm/gprs module that operates on a global scale of egsm 900MHz, DCS 1800MHz, PCS 1900MHz Three frequencies, provides up to 10 GPRS multi-channel types, and supports CS-1, CS-2, CS-3 and CS-4 four kinds of GPRS coding schemes. SIM300 internal function modules are:Keyboard and SPI type LCD interface for users to develop their own application equipment.Two serial ports with debug and data output to help developers develop products more ea

Establish communication links between two points (e.g. headquarters and branch offices, network centers and communities). According to customer needs and the actual survey of the situation, there are the following types of transmission:(1) AB two points between visual, no obstruction, no electromagnetic interference, or small interference, AB two points between the distance between the network bridge equipment communication distance requirements.Can use the point to point Way direct transmission

The extensive use of wireless networks also brings about the security of wireless networks. Because wireless networks are different from wired network physical node access controllability, the security of wireless networks deserves our attention. For the current wireless network, we can improve the security of the wireless network through the following settings. 1. Disable unauthorized access The key to ensuring the security of wireless access points is to prohibit unauthorized users from access

own hardware. The wireless transmission rate is mostly 54 M, and the maximum is no more than 150 M. it is meaningless to have a high Router speed. Look at the brand. Be sure to select a big-brand product, because the chip that really determines the performance of the wireless router is its. The chips used by major brands are of high quality and stable performance. Some brands use low-end chips to reduce costs. Although some parameters are high, the performance is unstable. Look at the

One of the most prominent advantages of the Siemens SX1 mobile phone is that it supports stereo MP3 and built-in FM. Although the original stereo PTT headset is of good quality, it can also be used as an antenna with built-in FM, however, one of the traditional methods of using a Siemens mobile phone is to use a headset adapter to enable the use of standard 5mm stereo headphones, such as senhaiser mx300/400/500. Therefore, the modification of the SX1

, it can be widely used for interconnection between different buildings. In addition, according to different protocols, wireless bridges can be divided into 802.11b or 802.11 in the GHz band and 802.11a wireless bridges in the GHz band. In the absence of high obstacle peaks or buildings), a pair of fast networking and temporary networking for field operations. The distance depends on the environment and the antenna, and now 7km point-to-point microwa

Wireless LAN has become one of the most commonly used network technologies. However, if we are faced with a weak network signal, how can we solve it. Here is a detailed introduction. Q: I am now using a wireless LAN, but I feel that the data transmission speed is very slow. Is there any solution? A: It is estimated that the signal status is poor. You can try to add an external antenna or adjust the wireless channel to improve the communication speed.

With the development of technology, the number of technical problems also increases. For wireless networks, improving or improving the security of networks also brings inevitable problems. Here we will introduce them in detail. The extensive use of wireless networks also brings about the security of wireless networks. Because wireless networks are different from wired network physical node access controllability, the security of wireless networks deserves our attention. For the current wireless

priority. This is why such technology has been vigorously promoted internationally in recent years. However, the New Fixed Wireless Access Network must be FWA with a wide bandwidth to meet the needs of the user's development of data communication trends. As a matter of fact, the wireless cellular network of mobile communication has evolved from the current second generation to the coming third generation, and even to the far-reaching fourth generation. It also attaches great importance to the c

For solutions with weak Wireless LAN signal, the problem of Wireless LAN signal is very hot. As the name suggests, there are many ways to solve the problem of Wireless LAN signal, that is, the virtual network channel of the wireless router. This article also introduces several popular wireless routers on the market. Q: I am now using a wireless LAN, but I feel that the data transmission speed is very slow. Is there any solution? A: It is estimated that the signal status is poor. You can try to a

will not be perfect. After all, those obstacles will directly affect the normal transmission of data signals in the wireless LAN. 2. When the distance between the remote network and the local LAN is relatively long, we can appropriately reduce the size of the network transmission bandwidth to achieve the purpose of long-distance data transmission. If we really need to implement long-distance wireless transmission, we may try to set up a wireless LAN relay station in the middle so as to bypass t

overlapping frequencies, and can even theoretically overlap to an infinite number. However, to increase the sensitivity of demodulation, LTE currently supports half of the overlapping wavelength of OFDM. MIMO In fact, one of the important reasons why LTE abandoned CDMA in the Early Days was that CDMA had poor support for MIMO, while the sub-carrier data used by OFDM was converting serial data into parallel data, parallel data can be well adapted to MIMO reception. (For the reason why CDMA is no

Wireless Networks are no stranger. Laptops and smartphones can all access wireless networks. This is what we often do in our lives, however, many people may encounter various usage errors when using wireless networks. I. The main factors affecting the wireless network are transmit power, accept sensitivity, and antenna gain. Currently, the main trend of wireless networks is in signal coverage and transmission rate, generally, the method to enhance the

radiation coupling. Transmission must have a complete circuit connection between the interference source and the sensor. Interference signals are transmitted along the connection circuit to the sensor. This transmission circuit can include the power supply, public impedance, grounding flat, resistance, inductance, capacitance and mutual inductance of wires, conductive components of the equipment. Radiation transmission is carried out in the form of electromagnetic waves, and the interference en

the user's device. The ground monitoring system of GPS working satellite includes one master station, three injection stations, and five monitoring stations. GPS signal receiver the task of GPS signal receiver is to capture the signals of the satellite to be tested selected based on the cutoff angle of a certain satellite height and track the operation of these satellites, transform, zoom in, and process the received GPS signals to measure the transmission time of GPS signals from the satell

example, some users put a wireless router near the microwave, and found that when the microwave oven work, the wireless network will appear inexplicable network failure, and the microwave after the network back to normal. Small fat found a lot of colleagues in the use of walkie-talkie, and in the intercom "harassment", the wireless network will naturally be affected. Therefore, it is also necessary to keep the "purity" of the wireless network environment as much as possible. Xiao Fat reminds

radiation transmission mode. Therefore, from the disturbed sensors, the interference coupling can be divided into two kinds: conduction coupling and radiation coupling. The conduction transmission must have a complete circuit connection between the jamming source and the sensor, and the jamming signal is transmitted to the sensor through the connection circuit, and the interference phenomenon occurs. The transmission circuit may include a conductor, a conductive component of the equipment, a p

meters, outdoor farthest not exceeding 50 meters. In addition, the antenna with high gain can be considered to solve this problem. Because of its no directionality, omni-directional antenna is used in the central station of point-to-point communication. Directional antenna has the maximum radiation or receiving direction, so the energy concentration, the gain r

price is hard to accept. However, it should be emphasized that each product has its own market positioning, wireless packages are mainly facing the "impoverished" of the primary users. Those who already have a certain basis to buy wireless package although some inconvenience, but not necessarily spend money. Here is a kind of practice is worth learning: in the market to find a "like-minded" friends, two people need to buy a set of wireless package. Contact each other before you break up so tha