Sharetechnote 4g throughput. Finding the Root Cause of the low throughput . 2. Example 1 > PHY throughput and RLC Throughput in a drive test Following plot is from the data captured by a drive test tool Azenqos Drive Test tool (AZQ Android) . I would say PDCP is a kind of interface between inside world and outside world. In many cases, I had been asked to be on-site saying "SOMETHING is NOT WORKING" (These two words are what we most frequently use, but most ambiguous word. 3. The most important factors to determine the ideal throughput are as follows : Number of RBs; MCS (Modulation Coding Scheme) which determines I_TBS; MIMO or SISO; The way to calculate the ideal throughput using these factors are explained in "Throughput Calculation Example" in Quick Reference page. Som to improve the cell-edge throughput; to increase the system throughput (See following 'Note'). Opinion 1 : I know the ideal max throughput is 100 Mbps, but I think it doesn't make much sense at least for a mobile device because in live network, you would never be in such a situation where a network allow such a huge resource allocation for any single UE and Radio Signal Quality also would not be good enough to achieve those throughput Overall Network Architecture. Followings are topics that will be covered in this page. This modulation order is defined as a Parameter called Qm in 3GPP and the relationship between MCS value and Qm is defined in a little bit differently for PDSCH and PUSCH in the three tables This throughput often get configured with the throughput calculated at the last step of this process. So, it is very likely that you would see low CQI when you see throughput drop in livenetwork test. So I want to talk about general technique for increasing the data rate. The simplest definition of performance test would be "to test if UE achieves maximum throughput at each and every layer". There are several factors that is critical to determine the throughput can be summarized in an illustration as shown below. I think I need to admit that I don't have enough experties to fill in this section, but I think I can some references that I found very useful. The plot in the middle (labeled as 'PHY throughput with HARQ ACK' is the amount of data getting ACKED per second from the reiever PHY layer. SDR. e, 0% BLER) around 30 dB SNR. Why CoMP ? As you may learned from the evolution path of any wireless communication, the strongest motivation for new technology and new feature is to increase the throughput and/or to increase the reliability of the communication. These are what I found in internet. NB-LTE stands for Narrow Band LTE. and tooooooooooooo confusing (at least very confusing to me). Note : I just learned (after discussion with expert engineer in this area) that the CoMP does not support special Multiplexing between TPs, so there would be no increase of the throughput in terms of Max throughput on UE side. What is Ideal/Expected throughput ? One of the most common questions that I have been getting for the past 10 years or so (probably from early HSDPA period and all the way up to now) was 'I have a UE with such and such category, what kind of throughput I need to get from this device ?' (Usually they carry the document like 36. For this mechanism to work properly, there should be a certain level of agreement between UE and the network about "which CQI value means which transport block size". Concept; Overall Configuration and Procedure; Mathematical Modeling of MIMO 4g/lte - rrc SIB(System Information Block) As the functionalities of LTE evolves and start interplay with other radio technologies (e. TBS (Transport Block Size) for BL/CE UE is determined by 36. (It would be a little bit tricky to draw a line between profile (A) and (B) because it would be difficult to achieve very high data rate without Throughput Calculation - TDD . 5G UE 4G/LTE - CCE Index CCE Index Calculation . Code Rate . 4G/LTE - Protocol Stack Typical Packet Call. LTE RACH in Details . This is the first message from UE to eNB when you power it on. The plot showing at the top (labeled as 'PHY Transmission Rate') is the amount of data being transmitted per second by PHY layer of the transmitter. Simply put, it is a technique to increase the data throughput by using multiple transmitter antenna and multiple reciever antenna. If you look at the table carefully, you would notice that the modulation This site is for everything on 4G/LTE. LTE level throughput (e. This site is for everything on 4G/LTE. If it is 4 x 4 and 4 layers, the performance would degrade further. 3G throughput (i. Comm. Ping Path from UE PC to Server PC : This site is for everything on 4G/LTE . Basic . One direction is 'higher and higher throughput' based on Carrier Aggregation (2 CC, 3CC and even 4CC) and the other direction is 'lower and lower throughput' with 'Low Cost' and 'Lower Energy Consumption'. You see there is pretty much gap between the two plots. ii) Low throughput does not necessarily mean low CQI. 1. For many people working in LTE, one of the most important question would be what is the maximum throughput for a network, device or network operator. < Increasing Modulation Depth > According to this plot, you may say you would get almost 100% peak throughput (i. MAX Throughput . I start seeing UEs supporting higher category and carrier aggregation and seeing troubleshoot case mainly for achieving maximum throughput. g, QPSK, 16 QAM, 64 QAM, 256 QAM). Proposed Scenarios 4G/LTE - LTE Advanced 64 QAM UL . We are doing various kinds of throughput related test in the lab, but the most meaningful test is to test in the field like downloading / uploading files in out doors sometimes walking along the street or in driving because those are most closes related to real user experience. And Why do you need this kind of special technique ? Does this mean that current LTE cannot achieve such a low throughput ? Of course there is no problem with the current LTE to work for such a low throughput application. Tech. Another difference is about TBS each subframe as marked in blue. 1-1: Transport block size table as in legacy LTE. Data Throughput LTE - Readings/Test Result TCP throughput is seriously decreased up to only 36% of maximum bandwidth. g, wlan, V2X, NR etc), the list of SIB is getting longer and longer. Overall RAN architecture of EN-DC can be illustrated as below (this is based on 37. Example 1 > Throughput, CQI, BLER while driving on a highway 4g/lte - catm / bl-ce NB-IoT . The throughput for a device working in a live net Opinion 1 : I know the ideal max throughput is 100 Mbps, but I think it doesn't make much sense at least for a mobile device because in live network, you would never be in such a situation where a network allow such a huge resource allocation for any single UE and Radio Signal Quality also would not be good enough to achieve those throughput 4G/LTE - Frame Structure / Downlink LTE DL Frame Structure in a Nutshell . The illustration and comments would need to be changes if the test condition gets different. CCE Index is the CCE number at which the control channel data (PDCCH) is allocated. Following is the mapping table for PUSCH (Uplink). Realistic LTE Performance (from Motorola) Field Trial for LTE Network System (from Fujitsu) Recommended Links for Throughput Test/Optimization The illustrations shown here are examples for a specific case (typical max throughput condition). But in a very high throughput configuration (e. Common Profiles . Drive Test . In this case, you may try transmitting/recieving multiple files simultaneously. MCS and Modulation Order . At least, you have to check the first three item (PHY/MAC condition) for sure. I got the log captured by the tool and exported the data as csv file and then plot it on Microsoft Excel. S1 mode retains the overlapping 4G and 5G cores. This is the most important item UE has to measure for cell selection, rese Recently as LTE Category goes higher, USB specification tend to become the bottleneck of the throughput. Even though they use a little bit different name, in all cellular technology (CDMA, GSM, WCDMA, LTE) there is a specific signal that perform the same function. This logic applies at least to 4G and 5G. Downlink TBS Determination . You may know that MCS (Modulation Coding Scheme) is related to Modulation Order (Modulation Depth, e. 4G to 5G Evolution; 4G vs 5G; Post-deployment Evolution (Cell Coverage, Test Report) Post-deployment Challenges; 5G Definitions; 5G Indication : upperLayerIndication; 5GMM; 5GSM; 5QI; 5G Release 16 Highlights; 5G Release 17 Highlights; 5G Release 18 Highlights; 5WWC/ATSSS; Acronyms; Agreed Items; AI/ML (Aritificial Intelligence / Machine Check-up before test . Performance like throughput, latency is superior in N1 mode compared to when anchored via 4G core in S1 mode. By "Inside World", I roughly mean "Network Access 4G/LTE - Access Control Quick Reference Access Confrol (ac-Barring, SSAC, EAB, Cell Barring) This site is for everything on 4G/LTE. However, one thing to be noticed is that the throughput would drop by 50% with only 2 dB SNR change at slighly lower than 30 dB SNR. This is from one of the most famous rule in communication theory called Shannon's law. There are three types of Frame Structure : Type 1 for FDD, Type 2 for TDD, Type 3 for LAA So, you would want to know the correlation between data throughput and the signal quality. In this section, I will go through a typical protocol sequence of LTE packet call. RACH stands for R andom A ccess Ch annel. Even before you try any throughput test (e. However, getting deeper into the details. In normal DL or UL subframe, TBS/subframe can be calculated in the same way as in FDD. UE Category for PHY layer throughput . Basic. TDD throughput calculation is very similar to FDD case as you see below. UE Category is the set of information (parameters) that defines the maximum throughput for a UE. WiFi. For now, I am illustrating only one specific cases but you can draw varying illustrations depending on situation. For the high level description of NB-LTE and some comparative view of other technology, refer to LTE-M/Category M/M1/M2 page. Simply put, the code rate can be defined as the ratio of the data rate that is allocated for a subframe and the maximum data rate that ideally can be allocated in the subframe. That correlation can be expressed as follows. 306 with the tables showing This site is for everything on 4G/LTE. Search Home Community. 213 10. Just in terms of theoretical throughput, M1 Downlink Max throughput is same as DL Category 0 which is 1 Mbps, but considering the repetivity scheduling, MPDCCH and PDSCH in separate subframes, Half Duplex operation, it will not be easy to achieve this throughput. But the issue is not with the low throughput, but with some other constraints. 4G/LTE - Measurement Multi Cell Measurement . Generally we do this kind of test in two different level, one at L1/PHY layer and one at IP layer. So, in stead of directly jumping into max throughput test, increase the throughput step-by-step and check CPU utilization (e. Followings are some of the items that is worth noticing from 3GPP 36. According to my experience, it would be relatively easy to achieve the optimum throughput for medium range of throughput (e. N1 mode requires deploying the new 5G core first. This is 2 x 2 and 2 layer case. This will be the backbone structure Example 1 > PHY throughput and RLC Throughput in a drive test Following plot is from the data captured by a drive test tool Azenqos Drive Test tool (AZQ Android) . This page will explain about various aspect of Measurement Process that is happening in a LTE. < 2014 ~ > I think most of the basic functionality (Single Cell, Throughput focused) for LTE UE became mature at least for a leading chipset manufacturer. The key difference is 'number of subframes /sec' parts as marked in red. As LTE evolves, the length of UE category list gets longer and longer, and the interpretation of the category gets more complicated, you will need to go through many tables listed below to figure out the exact throughput capability of a UE. Make it sure that your USB on the device and the server PC support enough throughput capacity for this kind of test. 5G NR Throughput Calculator | 5G NR Throughput Formula ; 5G NR Throughput calculator; Reference. Some TM is designed mainly to increase throughput, some are to increase communication reliability and some are to handle multiple users simultaneously etc. 213 Table 7. RSRP(Reference Signal Recieved Power) RSRP is the linear average of reference singal power (in Watts) accorss the specified bandwidth (in number of REs). Links on Throughput Test in the field. In NR, there are roughly two large frequency range specified in 3GPP. g, UDP, TCP), there are several critical steps to go through. The throughput at the last step in the process can be defined as physical layer throughput. not my tool, but I think all of these tools are based on the fornula in 3GPP as summerized above. CoMP . e, HSPA) is determined by a little bit different set of factors (parameters) but I would focus more on 4G/5G throughput. There are several different approaches for throughput testing and followings are a couple of possible sectors (or profiles) I can think of for throughput testing. g, Cat 6 or Cat 9 as of 2015 Jan timeframe) or very low throughput based on very small packet size. I think the first video only would give you a lot of insight and troubleshooting tips b One thing for sure for 5G would be that the required data throughput for 5G will be much higher (probably tens of Gbps) than 4G. g, you can monitor the CPU utilization using Windows Task Manager) Whenever you are doing the throughput test for your initial device, I always recommend you to check first if these assumptions are met before you are expecting any good throughput. 4G/LTE - Protocol Stack MAC I would be almost impossible to explain everything about LTE MAC in a single column without making it a thick book or without making everybody falling in sleep since MAC is the center of all LTE procedure. The data rate at this step is determined only by number of REs allocated for the data and the modulation method (QPSK, QAM, 16 QAM etc). I found a couple of examples of the max throughput calculator as listed below. g, over 100 Mbps), single file transfer at a time may not be enough to achieve max throughput. 2). g, 100 Mbps and over) is pretty tough task not only for IP stack, but also the IP application software and CPU utilization. HOT KEY Throughput TechSlide Flashcard . g, Cat 3 or Cat 4 max throughput), but it is not easy to achieve the extremley high throughput (e. In this section, I would focus more on L1/PHY layer performance test rather than IP layer throughput. In any technology Max Throughput Calculators. In other words, it means "The code rate is defined as the ratio between the transport block size and the total number of physical layer bits per subframe tha UMTS - CQI vs Throughput In live network for HSDPA, Network sends data with different transport block size depending on CQI value reported by UE. Normally this index changes for each Some TM is designed mainly to increase throughput, some are to increase communication reliability and some are to handle multiple users simultaneously etc. The practical throughput may vary widely depending on DL / UL 4G/LTE - Measurement Report NOTE : At high level view, it would not be difficult to understand overall concept of CSI. (The reason is same as above) iii) With low CQI, it is for sure that you cannot achieve the maximum throughput. The difference between M1 and legacy LTE lies. AI/ML/LLM 5G FR(Frequency Range) / Operating Bandwidth in Detail. Early July in 2016 (around Jul 10), the first version of 3GPP TS documents on NB IoT were posted and I started working on note based on these docum 2 CC Aggregation - 2x2 MIMO, Cat 3, 40 Mhz Aggregated BandWidth, 200 Mbps Throughput at IP layer 2 CC Aggregation - SISO, Cat 4, PUSCH enabled : HARQ Ack/Nack is carried by PUSCH 2 CC Aggregation - SISO, Cat 4, PUSCH diabled : HARQ Ack/Nack is carried by PUCCH Format 1b This throughput often get configured with the throughput calculated at the last step of this process. 340 - 4. With LTE Category 6 or higher, the max throughput is 300 Mbps or higher. For pure max throughput especially over 100 Mbps, you would need to use item i) combination, but for moderate throughput (below 100 Mbps) and in more realistic situation, I recommend you to try with combination ii) or iii). 1 and 4. LTE-BL/CE (LTE-M1) - MCS/TBS Determination . it would become much complicated . Learn about 4G DCI formats, fields, and decoding methods with clear diagrams and examples from ShareTechnote , a reliable source of wireless technology. Throughput Calculation - From UE Cateogory . One is what we usually call (sub 6 Ghz) and the other is what we usually call millimeter wave. In relatively low throughput, it would be enough to download/upload only one file at a time to achieve the max throughput. Amarisoft TechAcademy. RF. TCP Throughput . 3 TDD HARQ-ACK feedback procedures (I revised the statement a little bit to make it simple and hopefully clearer) I think everybody would know what MIMO is. . . 7. In this section, I would show you some examples showing the increased communication reliability with a couple of different Transmission Mode. 4G/LTE - Protocol Stack PDCP . S1 mode allows introducing 5G NR with existing 4G core. Latest Update : IP Network - SCTP (Update, Feb 2023) Learn From chatGPT (Update, Feb 2023) NR - NGAP (Update, Feb 2023) N1 mode simplifies the architecture with a common core for different access types. As you see here, UE is communicating with both LTE eNB and NR gNB in Radio side, but all those communication (signaling and data) are going through LTE core network. Category M(LTE-M) Recently (as of Sep 2015) you might have seen two obvious directions of LTE evolution. zaqngfx gzmh seu fnhd nsvlw cyybh lgitnm caoalk suz yvktt