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5G NR UE Initial Access Message Content
In this previous chapter we learnt about 5G NR initial access process in brief. In this chapter we shall see the important message contents. 1. RRCSetupRequest: UE sends a setup request IE:...
View Article5G NR RRC Message Protection
In this chapter we shall see which RRC messages can be sent: 1. RRC messages can be sent Unprotected prior to AS security activation. 2. RRC messages can be sent Unprotected after AS security...
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5G NR Access Process
Cell Search and Cell Selection 1. When a UE is powered on, it searches for a specific frequency according to Synchronization Raster as defined in TS 38.104. 2. UE tries to detect PSS/SSS to get...
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5G NR: Mobile Network Access Procedure
UE access procedure is as below: Step 1: UE is Switched ON Step 2: PLMN Selection PLMN Introduction PLMN stands for Public Land Mobile Network, will be established by the network and is used to provide...
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5G NR PDCCH order
PDCCH Order will be initiated by network to trigger a Random Access procedure. This is initiated when there is an upstream loss. When gNB has downstream data to send, PDCCH order will be used to...
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5G NR RRC States
In this chapter we shall have a look at the functionalities of different RRC States. There are 3 RRC states in 5G NR. 1. RRC Connected 2. RRC Inactive 3. RRC Idle RRC Connected State: 1. Initially UE...
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5G RAN Fronthaul, Midhaul and Backhaul, RRU, BBU, CU, DU
Fronthaul, Midhaul and Backhaul are used to connect RU, DU and CU and the core network together. They tells us about the transport network architecture. What is Fronthaul ? It is the link between RRU...
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5G NR: Interfaces available in 5G NR – Xn, NG, E1, F1, F2, CPRI
Above image shows overall architecture from 3GPP TS 38.300 specification. Xn interface exists between 2 base stations. Xn-U stands for Xn User Plane Xn-C stands for Xn Control Plane NG interface is...
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5G NR: Simple guide to C-RAN vs Cloud RAN vs vRAN vs O-RAN
In previous chapter we shall learned about RRU, BBU, CU, DU fronthaul, midhaul; In this chapter we shall learn about: D-RAN C-RAN cloud RAN vRAN oRAN D-RAN vs C-RAN vs vRAN vs O-RAN What is D-RAN? DRAN...
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5G NR: RAN Functional Splits
A single Central Unit can be connected to multiple Distributed Units. CU-CP will have RRC, PDCP CU-UP will have SDAP, PDCP Distributed Units will include RLC, MAC, H-PHY. F1 interface is used to...
View ArticleArrays: Find numbers with even number of digits
Problem Statement: You are given an array of integers. You need to return the count of the numbers that has even number of digits. Example Input arr = {12, 123, 1234, 12345, 123456} Output: 3 The...
View ArticleArrays: Find unique numbers that sum upto zero
Problem Statement: You are given an integer n. You need to return the integers that sum upto 0. Example Input: n = 5 Output: {-5, -1, 1, 2, 3} Solution Method 1: In this method, we will use the...
View ArticleArrays: Check If N and Its Double Exist
Problem Statement: You are given an array, you need to check if a number and its double exist in that array. Example Input arr = {10, 2, 5, 3} Output: True N = 5 M = 10. 5*2 = 10. So there exist 2...
View ArticleArrays: Check if 3 consecutive odds exist
Problem Statement: You are given an array, you need to check if there are 3 consecutive odds exist. If exist then return true else false. Example Input: arr = [2,6,4,1] Output: false Solution The...
View ArticleArrays: Merge sorted array inplace
Problem Statement: You are given with 2 sorted arrays, you need to merge the array in-place. You may assume that the first array will have enough space to accomodate all the array elements. Example:...
View ArticleArrays: Find triplet with minimum sum
Problem Statement: Given an unsorted array, you need to find 3 elements whose sum is the minimum. Example: arr = {-1, 2, 3, -2}; Output: -1 The elements are: -1, -2, 2 The solution in very simple, take...
View ArticleArrays: Program to check if an Array is Palindrome or not
Problem Statement: Given an unsorted array, check if it is palindrome array or not. Example: arr[] = {1, 2, 0, 2, 1} Output: Palindrome Solution: The solution is very simple, below are the steps to...
View ArticleSearching and Sorting: Find the majority element in the array
Problem Statement: You are given an arrya of repeating elements. You need to find and print the majority element. An element that appears more tha n/2 times, is called as majority element. Example...
View ArticleHello world!
Hello World, On Jan 1 2025, this website has be built ground up with a new website theme and a new hosting provider. This website will be much faster than compared to previous. We are planning to bring...
View ArticleSearching in a Nearly Sorted Array
Problem Statement: Given a sorted array where an element that should be present in i’th position, can be present in i-1’th position or i+1’th position. You are also given a key element. Check if the...
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