xbee wireless communication

Years ago to study how Android to achieve wireless communication function, wrote a small demo, recently nothing, so tidy up, and share with you. Earlier research found that Android want to achieve wireless communication has the following several technologies: 1,bluetooth has long been, easy to use, helpless speed is a

Key LTE technologies for wireless communication network learning ICIC (20141220), lteicic ICIC: Inter Cell Interference Coordination, Inter-Cell Interference Coordination technology. Cell interference is a key indicator that limits cell network cell throughput, especially for cell edge users. Because the Frequency Multiplexing factor supported by the LTE system is 1, meticulous management of inter-cell inte

In view of the previous day to write a relevant knowledge point, and occasionally due to work reasons, did not follow up every day, so decided to write today another on the key technology of LTE knowledge, but also the last son.SON: (self organized network) ad-organized networks ;Contains three aspects: self-configuring, ANR (Automatic neighborhood optimization), MRO (switching self-optimizing);Automatic configuration is the base station cell equipment automatic completion of the basic parameter

While we are still lamenting that the next generation of 802.11n Wi-Fi is so fast, Japanese scientists have begun to study the key technologies of the next generation of wireless networks. They recently broke the world record for Wi-Fi wireless transmission speed, with a transfer rate of 20 times higher than the current Wi-Fi transmission speed. By using a 1mm-cubic-meter device as a resonant diode, scie

Ask the communication problem between two wireless NICs ~ -- Linux general technology-Linux programming and kernel information. The following is a detailed description. I have two wireless NICs, the chip is intesil prism 2.5, and the driver I have installed is hostap. Now I want to communicate with the two NICs, And I want to implement it through a bridge, but no

today, let's elaborate on the evolution of GSM,TD to LTE :Let's take a look at the next evolution:2G,3G network in the architecture has four physical devices, LTE in the network architecture only eNodeB and access gate two physical devices, removed the original 3G network support circuit switching (circuit-switch) function, transform the IP routing network of the packet, The complexity of the core network is greatly simplified;The hosting service architecture meets the diverse QoS requirements:F

, frequency of the three three-dimensional parameter structure to see OFDMA.The effective wave of orthogonal post data, transverse is frequency, sub-carrier interval 15K, longitudinal axis is time, 1ms Dispatch once, the CP is inserted between each layer wave to reduce ISI (inter-symbol interference).For the Fourier transform those algorithms, do not go into the deep, I believe that you also have a certain understanding of OFDM,OFDMA, tomorrow we continue to explore other key technologies.Taking

divided into FFR and SFR according to the reuse degree of Edge band.FFR (fractional Frequency reuse): Partial frequency multiplexing;SFR (Soft Frequency reuse): soft frequency multiplexing;Frequency multiplexing factor of 1 (same frequency multiplexing)Summary: Would rather sacrifice a certain bandwidth to avoid the edge of the same frequency interference technology, called ICIC (inter-cellinterference coordination, inter-cell interference coordination).I CIC is a little introduced here, you ar

The following describes how to read and obtain information from cnttr and other network resources. In wireless communication, there are two kinds of fading,1. Large-scale fadingThat is, the distance between the mobile station and the base station space and the buildings are blocked when the radio waves are transmitted;2. Small Scale fadingIncluding the time Selective Fading Caused by the relative motion of

was opening quickly, which led us to the station, but too late.In the case of slow channel changes, such as indoor or nomadic access services in large cities, it is necessary to use the closed-loop MIMO to further improve the performance of the shampoo.Closed-loop system is the receiving end of the information channel feedback to the transmitter, and then the transmission of data encoding, beamforming or antenna selection and other operations.The feedback method is divided into full feedback or

of the pass-through channel parameters. For example, in the case of a heart rate watch paired with a heart rate band, it is common for xiaoming to wear a heart rate band and then operate the heart rate meter for pairing. According to Xiao Ming's operating habits, we can set the heart rate belt in the opening of the 10s pre-pairing bit, 10s automatically reset the pairing bit, so that, as long as the nearby surrounding other users not in 10s to open another heart rate belt, Xiaoming will be able

--uhvlZRAABIsNyAVSY871.jpg "title=" capture. PNG "alt=" Wkiom1wq--uhvlzraabisnyavsy871.jpg "/>Therefore, the maximum ratio of the letter to noise is the combination of MRC merger.Note: The above content is from Baidu Library "maximum ratio merger can obtain the maximum signal to noise ratio proof"Continue to analyze at this time and signal to noise ratio snr, may make 650) this.width=650; "Src=" http://s3.51cto.com/wyfs02/M02/6F/0F/wKioL1WQ_ Ghbyqohaaatcj9zwfa723.jpg "title=" capture. PNG "alt="