isotropic antenna

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

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 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

The antenna pattern is also called the Radiation Direction map (radiation pattern), the far-field direction map (Far-field pattern). The antenna gain is not obtained from the pattern above, and the directional coefficients are obtained from the direction graph. Antenna gain = directional coefficient * antenna efficienc

http://acm.pku.edu.cn/JudgeOnline/problem?id=3020 Antenna Placement Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 2319 Accepted: 1082 Description The Global aerial Centre has been allotted the task of building the fifth generation of mobile phone Nets in Sweden. The most striking reason so they got the job, is their discovery of a new, highly noise resistant,

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

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

First of all, a misunderstanding is: the more the antenna coverage, the more the antenna signal stronger MIMO (Multiple-entry) is the technology of multiple antennas is from the 802.11N protocol only after the 802.11a,b,g have not. That is to say, the first generation of routers (802.11n ago) will never have more than one antenna. And you bought a new 3-day line

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

"POJ 3020" antenna Placement The maximal independent set problem of binary graphs' O ' means that the break point requires that all * connections be connected to one or two consecutive lines per route *The maximum match can satisfy only the longest path that can be formed by only two consecutive connections, and the points that are not connected need to be circled separately.i.e. N (total * number)-m (maximum match) +m (maximum match)/2(due to the fac

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