antenna book

In the Last Post, "LTE Physical Transmission Resources (3)-time-frequency resources," the final mention of Pcfich and other downstream physical channels, this blog post originally wanted to write Pcfich channel, but in preparation for writing Pcfich, found the need to use the antenna port related content, and these content is not yet written. So this paper first write the antenna port and downlink reference

obtained by measuring the polarization. If not added, this book says that the direction map refers to the field intensity amplitude direction map. The mapping of three-dimensional spatial direction map is very troublesome, in the actual work, generally only need to measure the horizontal plane and the vertical plane (that is, XY plane and XZ plane) of the direction map on the line. Figure 1 Measuring the coordinates of the direction map The

of the method of transmitting information. Other MIMO, in terms of the concept may be better understood, such as 2 transmitting antenna t1t2 respectively to two receiving antenna R1R2 launch, then the equivalent of two people working at the same time, speed up twice times and so on. However, it is very complicated and time-consuming to compute the hardware, on the one hand, we need multiple receiving ante

With the rapid development of modern Wireless communication technology, Wireless Local Area network (WLAN) is widely used. WLAN uses wireless communication technology to transmit data, voice and video signals in the air, so that users can exchange information anytime, anywhere. Worldwide Interoperability for MicrowaveAccess (WiMAX) is a new broadband wireless access technology that provides high-speed internet-oriented connections, and the data transmission distance is up to 50 km. Currently, WL

Recently saw a classmate in order to enhance the mobile phone GPS signal, the antenna DIY to the outside, pulled a very long antenna, their own in the suspicion that this is in line with the principle of antenna design, can really make the signal enhancement? So find the following article to learn.1. RFID Fundamentals RFID (radio frequency identification) is a

Mobile phone antennas can be divided into PIFA antennas and Single Pole antennas. As debugging becomes more difficult, a new IFA antenna is added. PIFA AntennaPIFA antenna has the same requirements on antenna height and area. Generally, the dual-band height must be above 5mm. The proposed height of PIFA antenna must b

In general, our common antenna tests in engineering practice are divided into the following types: Near-Field Test In the near-field antenna test, the distance from the test probe to the plane of the tested antenna port is about 3 λ 5 λ. In this case, the antenna test is near-field test.The near-field

1. Is the effect of placing an external antenna in the trunk of the car station worse than that in the middle of the roof?A: There are four main indicators of the vehicle's antenna: maximum withstand power, center frequency, bandwidth, and standing wave ratio.The first indicator is generally not taken into consideration, because generally, the maximum withstand power of the external

When you are using a wireless network, you are sure to experience wireless network signal quality problems. To solve these problems, in addition to reducing the shielding, reduce the interference of the same band equipment, the most effective way is to replace the high gain antenna, with the antenna to enhance the transmission effect of wireless network, coverage. However, the purchase of wireless gain

In wireless networking, we need Wireless antennas to help increase the coverage area. Especially in office buildings, we often see long, mushroom-like wireless antennas, which are used to enhance wireless signals. For wireless antenna products, let's take a look at the following introduction. For many wireless users, the deployment of every wireless lan wlan is not a simple task. The home network may be a good solution. For some enterprise networks, d

The antennas are clear to everyone. We used to build antennas on the roof to receive TV signals. However, with the development of the times, we have seldom seen strange TV antennas, instead of Various wireless antennas. What is a wireless antenna? Of course it is an antenna related to wireless signals. What is a wireless antenna? Before answering this question, l

An antenna (antenna) is a transducer that transforms a traveling wave propagating on a transmission line into an electromagnetic wave propagating in a unbounded medium (usually a free space), or in reverse. A component used in radio equipment to transmit or receive electromagnetic waves. Radio communications, radio, television, radar, navigation, electronic confrontation, remote sensing, radio astronomy and

With the development of global 4G networks in full swing in recent years, how to simplify the deployment of remote adjustment antennas and improve their reliability has become a new concern of operators for the antenna feed system. Due to its inherent requirements for on-site access, low operation and maintenance efficiency, and affected antenna radiation performance, the method of mechanical tilting optimi

With the popularization of 3G technology and the development of wireless standards and technologies such as LTE, NFC, Bluetooth 4.0, cmms B, and MIMO, mobile Terminals need to integrate multi-band main antennas (supporting 2g, 3G, LTE and other multi-standard), as well as GPS, BT, WiFi, NFC, wireless charging and other antennas. As a result, terminal antenna engineers are facing huge challenges: Antenna siz

The antenna theory of the experts is simple: http://www.52rd.com/bbs/Detail_RD.BBS_187060_42_1_3.html The problem must be analyzed in essence. The above two images can be used for analysis. Antenna evolution can be analyzed by transmission lines. The transmission lines are represented by the same axis. The same axis is divided into core, insulation layer, and shielding network. When the complete Coa

Reference: 1. wikipedia The dipole antenna is the simplest and most widely used class of antenna. It consists of identical conductive elements such as metal wires or rods, which is usually bilaterally symmetrical. Each side of the feedline to the transmitter or receiver was connected to one of the conductors. Dipoles is resonant antennas, meaning that the elements serve as resonators, with standing waves

Smart antenna is a kind of bidirectional antenna installed in the base station, which obtains directivity through a set of fixed antenna units with programmable electronic phase relation, and simultaneously obtains the directional characteristic of each link between the base station and the mobile station. The principle of the smart

In the previous article, we introduced what is a wireless antenna and the two basic parameters of the antenna. Next we will introduce in detail what are the outdoor wireless antennas. We have already introduced indoor wireless antennas. We will not repeat them here. Outdoor wireless antenna 1. Omnidirectional Antenna A

#include 2#include 3#include 4 using namespacestd;5 intmatch[ the];6 structnode{7 intx, y;8}dir[4]={{1,0},{-1,0},{0,1},{0,-1}};9Vectorv;Ten intn,m,cnt; one Charmatrix[ -][ -]; a intmp[ -][ -]; - intbook[ the]; - inte[ the][ the]; the voiddeal () { - for(intx=0; x) { - for(inty=0; y) { - if(matrix[x][y]!='*')Continue; + intI=mp[x][y]; - for(intD=0, xx,yy; d4; d++) { +xx=x+dir[d].x; ayy=y+dir[d].y; at if(xx0|| X>=n | | yy0|| Yy

Source: Length calculation method of single whip antennaWhen doing radio frequency transmission, the choice and length of the antenna has a great influence on the reception sensitivity of the signal, the following is a brief overview of the antenna calculation:Alternating currents in a piece of metal wire can be emitted to the space to alternately change the induced electric field and the induced magnetic f