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How to Reduce Website Latency Using Cloudflare

This guide shows you how to put your website behind Cloudflare (Free Plan) to reduce global latency and improve performance. What This Will Do Visitors in Asia, i.e., India, will hit the Cloudflare Mumbai edge server. Cloudflare fetches content from your origin server (Australia) Static files get cached globally Latency drops dramatically Step 1 — Create Free Cloudflare Account Go to https://cloudflare.com Click Sign Up Choose the Free Plan Click Add a Site Enter your domain: example.com Step 2 — Cloudflare Scans DNS Cloudflare will automatically detect your DNS records. Make sure: Your A record IP matches your current hosting server IP The orange cloud ☁️ is ON (Proxied) Type: A Name: @ IP: 123.123.123.123 Proxy status: Proxied If it’s gray → click it → turn orange. Step 3 — Change Nameservers (MOST IMPORTANT) Cloudflare will give you two nameserve...

Channel Estimation using Hybrid Beamforming

For channel estimation in hybrid architecture: Here I will discuss communication between a BS (base station) and vehicles for mm Wave communication channel. Both N BS and N v have linear arrays (ULAs), with half-wavelength spaced antenna elements in a compact area uniformly. Let assume, f n is the beamforming vector at BS side. BS need to transmit a symbol, s , such that | s | 2 = 1. On the other hand, vehicle assigns a unit-norm measurement vector w m . Now, the signal received at MS (user) side is written by …………………………………………………..(vii) Where, H = N v X N BS matrix σ 2 = variance of white Gaussian noise …………………………………………………………….(viii) where α = channel gain a v (θ)= vehicle’s ULA array response for line of sight AOA (θ) a BS (φ)= For Line of sight AOD (φ), BS’s ULA steering vector response represented as ……………………………(ix) (Garcia, 2016) Equation (ix) showing phase difference in succeeding antenna elements of MIMO at vehicle and BS side, respectively. . …………………………………………...

Digital Beamforming for Multi-User scenario

Baseband precoding: Baseband precoding is to cancel interferences between multi stream in MIMO communication. Here in hybrid precoding each RF chains are connected to more than one antenna element. And each RF chain responsible of one data stream The signal that has been sent can be denoted as. x=Ds ........................................................(i) Where, x = transmitted signal vector D = N t X N r digital precoder s = N r X 1 symbol vector Now, received signal vector y at receiver side, y= √ρHDs + n …………………………….. (ii) Here, ρ = average received power H =channel matrix ( N r X N t ) n = additive white Gaussian noise vector Digital Beamforming for Multi-User scenario Here in above figure 6.2, BS uses N BS antennas and N BS RF chains for communication with U mobile stations (MSs) simultaneously. N MS antennas are there in each MS. The total number of data streams for communication is equal to the number of antennas on the receiver side, N MS U, wh...

Channel estimation using Beam Steering

Channel estimation using Beam Steering For millimetre wave communication we need site specific information about the particular environment for smooth communication between BS and UE (User Equipment) because propagation distance of millimetre wave in atmosphere is limited without beamforming or directional transmission of signal. Figure 1: Beam training with analog architecture Beam steering is usually used to find best beam pair between BS an UE. To enable beam steering we use codebook where like this Where each element in codebook indicates the quantified azimuth (elevation) angles of departure and arrival are, respectively, ϕ t l (θ t l ) and ϕ l r (θ r l ), That are assumed to cover the full ranges of angle of arrivals/departures (AoDs/AoAs) uniformly. But one of the limitation of analog beamformer is that it can enable only single data stream between Tx and Rx. So, we need to deploy hybrid architecture. Fig 2: Architecture of transceiver at Tx & Rx both which c...

Antenna array response

Antenna array response In case of wireless communication signal reaches receiver thru multipath. Multipath signals are correlated if antenna elements are closely packed in a compact region. Figure 1: Illustration of multipath communication in wireless environment For a path l (say) is described along following parameters Angle of arrival θ r l ; Angle of departure θ t l ; Complex channel gain α l ; Figure 2: Directional cosine vectors at receiver side for transmission from Tx Figure 3: Antenna array response at different antenna array and simplified channel model Let assume, in the above figure 2, BS is transmitting at receiver side and receiver antenna array contain four ULA antenna elements. Then we can observe in the figure that to reach 2 nd element (from left) the signal has to travel more distance with compare to 1 st element. The extra path distance will be dcosθ or λ/2*cosθ as the antenna elements are spaced in half wave length interval. That’s why there wi...

UWB and mm-Wave Indoor Communication

UWB and mm-Wave Indoor Communication 8.1. Introduction: Higher frequency bands are intended for wireless and wired broadband networks. Since it allows for more spectrum coverage and higher bandwidth demands. To ensure that a wireless communication device performs well, it is essential to define the radio transmission channel. Wireless communication is also becoming popular in industrial operation day by day. It is needed to control appliances i.e, automated vehicles, machine to machine communication in factories, etc. compare to wired communication, and wireless communication is cost efficient. Fifth generation (5G) technology has gathered a great interest in industrial operation due to its low reliable latency. Industrial applications need more careful evaluation. Industrial environment faces a great quantity of reflective metal surfaces. So it is required to develop a suited physical layer for this particular environment. Indoor residential: This environment is suitable for home...

Ray tracing Method

  Ray tracing Method Because of its advantages in industry, wireless networking is increasingly growing to new heights, with the ability to provide high-speed information sharing between handheld devices anywhere in the globe. Any empirically based radio propagation model is useful for a specific application. We can't adapt a model developed for one application to another, and these models lack the generality and ease of use that a simple theoretical formulation provides. As a result, deterministic models that can be used to various conditions without affecting the precision. It is basically based on EM wave propagation characteristics. Reflection and transmission Dielectric Boundary: For radio wave propagation, the physical properties of the walls and other materials for which it reflect and scatter radio waves are determined by boundary conditions. In practise, specifying information with precision less than the wavelength is impractical in dynamic environments. Ray tracing (site...

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