The document provides an overview of LTE physical layer specifications including OFDMA frame structure, resource block structure, protocol architecture, physical channel structure and procedures, UE measurements like RSRP and RSRQ, and key enabling technologies of LTE such as OFDM, SC-FDMA, and MIMO. It describes the LTE requirements for high peak data rates, low latency, support for high mobility users, and enhanced broadcast services.
In this paper, we discussed about LTE system throughput calculation for both TDD and FDD system.
3GPP LTE technology support both TDD and FDD multiplexing. The paper describes all the factors which affect the throughput like Bandwidth, Modulation, UE category and mulplexing. It also describes how we get throughput 300Mbps in DL and 75Mbps in UL and what are assumptions taken to calculate the same.
Paper describes the steps and formulae to calculate the throughput for FDD system for TDD Config 1 and Config 2.
The throughput calculations shown in this paper is theoretical and limited by the assumptions taken to calculate for calculations
This is presentation by Keysight technologies on 5G NR Dynamic Spectrum Sharing. Very well articulated presentation as always by Keysight. Details on the 3GPP support for NR DSS implementation in LTE bands in Rel 15 and Rel 16.
An introduction to Cellular communications Signaling, Specifically LTE Signaling.
Introducing 3GPP approach to handover and handoff mechanisms.
LTE architecture by alcatel-lucent included in this presentation.
This presentation focuses on mobility management protocols such as GTP-C and GTP-U.
In this paper, we discussed about LTE system throughput calculation for both TDD and FDD system.
3GPP LTE technology support both TDD and FDD multiplexing. The paper describes all the factors which affect the throughput like Bandwidth, Modulation, UE category and mulplexing. It also describes how we get throughput 300Mbps in DL and 75Mbps in UL and what are assumptions taken to calculate the same.
Paper describes the steps and formulae to calculate the throughput for FDD system for TDD Config 1 and Config 2.
The throughput calculations shown in this paper is theoretical and limited by the assumptions taken to calculate for calculations
This is presentation by Keysight technologies on 5G NR Dynamic Spectrum Sharing. Very well articulated presentation as always by Keysight. Details on the 3GPP support for NR DSS implementation in LTE bands in Rel 15 and Rel 16.
An introduction to Cellular communications Signaling, Specifically LTE Signaling.
Introducing 3GPP approach to handover and handoff mechanisms.
LTE architecture by alcatel-lucent included in this presentation.
This presentation focuses on mobility management protocols such as GTP-C and GTP-U.
LTE specifications support the use of multiple antennas at both transmitter (tx) and receiver (rx). MIMO (Multiple Input Multiple
Output) uses this antenna configuration.
ď§ LTE specifications support up to 4 antennas at the tx side and up to 4 antennas at the rx side (here referred to as 4x4 MIMO
configuration).
ď§In the first release of LTE it is likely that the UE only has 1 tx antenna, even if it uses 2 rx antennas. This leads to that so called
Single User MIMO (SU-MIMO) will be supported only in DL (and maximum 2x2 configuration).
What LTE Parameters need to be Dimensioned and OptimizedHoracio Guillen
Â
How to Dimension user Traffic in 4G networks
What is the best LTE Configuration
Spectrum analysis for LTE System
MIMO: What is real, What is Wishful thinking
LTE Measurements what they mean and how they are used
How to consider Overhead in LTE Dimensioning and What is the impact
How to take into account customer experience when Designing a Wireless Network
LTE specifications support the use of multiple antennas at both transmitter (tx) and receiver (rx). MIMO (Multiple Input Multiple
Output) uses this antenna configuration.
ď§ LTE specifications support up to 4 antennas at the tx side and up to 4 antennas at the rx side (here referred to as 4x4 MIMO
configuration).
ď§In the first release of LTE it is likely that the UE only has 1 tx antenna, even if it uses 2 rx antennas. This leads to that so called
Single User MIMO (SU-MIMO) will be supported only in DL (and maximum 2x2 configuration).
What LTE Parameters need to be Dimensioned and OptimizedHoracio Guillen
Â
How to Dimension user Traffic in 4G networks
What is the best LTE Configuration
Spectrum analysis for LTE System
MIMO: What is real, What is Wishful thinking
LTE Measurements what they mean and how they are used
How to consider Overhead in LTE Dimensioning and What is the impact
How to take into account customer experience when Designing a Wireless Network
This documents will cover basic LTE principles along with some brief impression about LTE features. Additionally, LTE Link Budget, LTE Coverage & Capacity Planning and Cell Radius calculation methodology have been depicted comprehensively in this document.
Dev Dives: Train smarter, not harder â active learning and UiPath LLMs for do...UiPathCommunity
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đĽ Speed, accuracy, and scaling â discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Miningâ˘:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing â with little to no training required
Get an exclusive demo of the new family of UiPath LLMs â GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
đ¨âđŤ Andras Palfi, Senior Product Manager, UiPath
đŠâđŤ Lenka Dulovicova, Product Program Manager, UiPath
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
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Are you looking to streamline your workflows and boost your projectsâ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, youâre in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part âEssentials of Automationâ series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Hereâs what youâll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
Weâll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Donât miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
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The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. Whatâs changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
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In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
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Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
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Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
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In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
⢠The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
⢠Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
⢠Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
⢠Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
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A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
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Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
Â
Here is something new! In our next Connector Corner webinar, we will demonstrate how you can use a single workflow to:
Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But thereâs more:
In a second workflow supporting the same use case, youâll see:
Your campaign sent to target colleagues for approval
If the âApproveâ button is clicked, a Jira/Zendesk ticket is created for the marketing design team
Butâif the âRejectâ button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
Â
The field of Information retrieval (IR) is currently undergoing a transformative shift, at least partly due to the emerging applications of generative AI to information access. In this talk, we will deliberate on the sociotechnical implications of generative AI for information access. We will argue that there is both a critical necessity and an exciting opportunity for the IR community to re-center our research agendas on societal needs while dismantling the artificial separation between the work on fairness, accountability, transparency, and ethics in IR and the rest of IR research. Instead of adopting a reactionary strategy of trying to mitigate potential social harms from emerging technologies, the community should aim to proactively set the research agenda for the kinds of systems we should build inspired by diverse explicitly stated sociotechnical imaginaries. The sociotechnical imaginaries that underpin the design and development of information access technologies needs to be explicitly articulated, and we need to develop theories of change in context of these diverse perspectives. Our guiding future imaginaries must be informed by other academic fields, such as democratic theory and critical theory, and should be co-developed with social science scholars, legal scholars, civil rights and social justice activists, and artists, among others.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
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Clients donât know what they donât know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clientsâ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Â
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
3. LTE Requirements
⢠Peak bit (not data) rate
â 100 Mbps DL/ 50 Mbps UL within 20 MHz bandwidth (i.e., SISO)
⢠Up to 200 active users in a cell (5 MHz)
⢠Less than 5 ms user-plane latency condition (i.e., single user with single data
stream)
⢠Mobility
â Optimized for 0 ~ 15 km/h
â 15 ~ 120 km/h supported with high performance
â Supported up to 350 km/h or even up to 500 km/h
⢠Enhanced multimedia broadcast multicast service (E-MBMS)
⢠Spectrum flexibility: 1.25 ~ 20 MHz
⢠Enhanced support for end-to-end QoS & QoE
4. LTE Enabling Technologies
⢠OFDM (Orthogonal Frequency Division Multiplexing) for Down Link
⢠Frequency domain equalization
⢠SC-FDMA (Single Carrier FDMA) for Up Link
⢠Utilizes single carrier modulation and orthogonal frequency Multiplexing using
DFT-spreading in the transmitter and frequency domain equalization in the receiver
⢠A salient advantage of SC-FDMA over OFDM/OFDMA is low PAPR.
⢠Efficient transmitter and improved cell-edge performance
⢠MIMO (Multi-Input Multi-Output)
⢠e.g., Open loop, Close loop, Diversity, Spatial multiplexing
⢠Multicarrier channel-dependent resource scheduling
⢠Fractional frequency reuse
⢠Active interference avoidance and coordination
5. LTE Key Features
⢠Multiple access scheme
⢠DL: OFDMA with CP (Cyclic Prefix)
⢠UL: Single Carrier FDMA (SC-FDMA) with CP
⢠Adaptive modulation and coding
⢠DL/UL modulations: QPSK, 16QAM, and 64QAM
⢠Convolutional code and Rel-6 turbo code
⢠Advanced MIMO spatial multiplexing techniques
⢠(2 or 4)x(2 or 4) downlink and uplink supported
⢠Multi-user MIMO also supported
⢠Support for both FDD and TDD
⢠H-ARQ, mobility support, rate control, security, and etc...
6. LTE Standard Specifications
Specification
index
Description of contents
TS 36.1xx Equipment requirements: Terminals, base stations, and repeaters
TS 36.2xx Physical layer
TS 36.3xx Layers 2 and 3: Medium access control, radio link control, and
radio resource control
TS 36.4xx Infrastructure communications (UTRAN = UTRA Network) including
base stations and mobile management entities
TS 36.5xx Conformance testing
8. OFDM (2/3)
Figure 2. OFDM useful symbol generation using an IFFT
OFDM essential concept: Subcarrier spacing ( f) = 1/Tu
9. OFDM (3/3)
⢠High spectrum efficiency
⢠Inter-OFDMsymbol-interference caused
by Multipath Delay Spread
⢠Inter-carrier-interference caused by
Doppler Frequency Spread
⢠High Peak to Average Power Ratio (PAPR)
caused by multiple frequency harmonics
⢠UL SC-FDMA reduces PAPR, but of more
signiďŹcance - particularly for the ampliďŹer
â is the Cubic Metric (CM)
19. Cell Search
⢠Cell search: UE acquires time and frequency synchronization with a cell and detects
the cell ID
⢠Based on BCH (Broadcast Channel) signal and hierarchical SCH (Synchronization Channel)
signals.
⢠P-SCH (Primary-SCH) and S-SCH (Secondary-SCH) are transmitted twice per radio
frame (10 ms) for FDD
⢠Cell search procedure
⢠5 ms timing identified using P-SCH
⢠Radio timing and group ID found from S-SCH
⢠Full cell ID found from DL RS
⢠Decode BCH
20. UE Measurements (1/4)
⢠In cellular networks, when a mobile moves from cell to cell and performs cell
selection/reselection and handover, it has to measure the signal strength/quality of
the neighbor cells.
⢠In UMTS, a UE measures Carrier RSSI, CPICH RSCP, and CPICH Ec/No on preamble.
⢠In LTE network, a UE measures two parameters on reference signal: RSRP (Reference
Signal Received Power) and RSRQ (Reference Signal Received Quality).
21. UE Measurements (2/4)
Definition Reference signal received power (RSRP), is defined as the linear average over
the power contributions (in [W]) of the resource elements that carry cell-
specific reference signals within the considered measurement frequency
bandwidth.
For RSRP determination the cell-specific reference signals R0 according TS
36.211 [3] shall be used. If the UE can reliably detect that R1 is available it may
use R1 in addition to R0 to determine RSRP.
The reference point for the RSRP shall be the antenna connector of the UE.
If receiver diversity is in use by the UE, the reported value shall not be lower
than the corresponding RSRP of any of the individual diversity branches.
diversity branches.
Applicable for RRC_IDLE intra-frequency,
RRC_IDLE inter-frequency,
RRC_CONNECTED intra-frequency,
RRC_CONNECTED inter-frequency
3GPP TS 36.214 V9.2.0
22. UE Measurements (3/4)
Definition Reference Signal Received Quality (RSRQ) is defined as the ratio NĂRSRP/(E-
UTRA carrier RSSI), where N is the number of RBâs of the E-UTRA carrier RSSI
measurement bandwidth. The measurements in the numerator and
denominator shall be made over the same set of resource blocks.
E-UTRA Carrier Received Signal Strength Indicator (RSSI), comprises the linear
average of the total received power (in [W]) observed only in OFDM symbols
containing reference symbols for antenna port 0, in the measurement
bandwidth, over N number of resource blocks by the UE from all sources,
including co-channel serving and non-serving cells, adjacent channel
interference, thermal noise etc.
The reference point for the RSRQ shall be the antenna connector of the UE.
If receiver diversity is in use by the UE, the reported value shall not be lower
than the corresponding RSRQ of any of the individual diversity branches.
Applicable for RRC_IDLE intra-frequency,
RRC_IDLE inter-frequency,
RRC_CONNECTED intra-frequency,
RRC_CONNECTED inter-frequency
23. UE Measurements (4/4)
⢠For example, assume that only reference signals are transmitted in a
resource block, and that data and noise and interference are not considered.
In this case RSRQ is equal to (1/2) or -3 dB. If reference signals and
subcarriers carrying data are equally powered, the ratio corresponds to
(1/12) or -10.79 dB.
⢠RSRQ is not suitable for LTE measurement. We use RSRP and Ăs/Iot measurement defined in TS
36.133 to determine the intra frequency cell delectability.
⢠An intra frequency cell is considered to be detectable if: RSRP|dBm > -124 dBm for Bands 1, 4, 6,
10, 11, 18, 19, 21, 33, 34, 35, 36, 37, 38, 39, 40 and RSRP Ăs/Iot -4 dB,âŚ).
Ăs: Received energy per RE (power normalized to the subcarrier spacing) during the useful part of the symbol,
i.e. excluding the cyclic prefix, at the UE antenna connector.
Iot: The received power spectral density of the total noise and interference for a certain RE
(power integrated over the RE and normalized to the subcarrier spacing)
as measured at the UE antenna connector.
CPICH RSCP: Received Signal Code Power, the received power on one code measured on the Primary CPICH.
UMTS FDD carrier RSSI: The received wide band power, including thermal noise and noise generated in the receiver,
within the bandwidth defined by the receiver pulse shaping filter.
CPICH_Ec/No: The received energy per chip divided by the power density in the band. If receiver diversity is not in use
by the UE,
the CPICH Ec/No is identical to CPICH RSCP/UTRA Carrier RSSI.
24. Reference Signal with 6 frequency-shift
predefined pattern
A
B
E
F
B
E
D
A
B
D
A
C
C
D
E
F
C
A
A
A
B
B
B
C
C
C
E
E
E
D
D
D
F
F
F
F
25. Conclusions
⢠LTE Requirements and Key Features
⢠OFDMA Frame and Resource Block Structures
⢠Physical Channel Structure and Procedure
⢠UE measurements
⢠RSRP & RSRQ
26. Reference
[1] 3GPP LTE http://www.3gpp.org/ftp/Specs/html-info/36-series.htm.
[2] 3GPP TR 25.892; Feasibility Study for Orthogonal Frequency Division Multiplexing (OFDM) for
UTRAN enhancement (Release 6)
[3] S. Sesia, et.al. âLTE-The UMTS Long Term Evolution- from Theory to Practiceâ, John Wiley &
Sons Ltd. (Good book on PHY layer concept)
[4] H. Holma, et.al. âLTE for UMTS OFDMA and SC-FDMA Based Radio Accessâ, John Wiley & Sons
Ltd. (Good book on System Architecture concept)
[5] H.G. Myung, Technical Overview of 3GPP LTE. http://hgmyung.googlepages.com/scfdma.pdf
[6] P. Wang, et. Al. âRF Pattern Matching Performance in LTEâ, Polaris Wireless internal report,
April 17, 2010.
28. LTE bit rate calculation
⢠From the 3gpp specification:
-1 Radio Frame = 10 Sub-frame
-1 Sub-frame = 2 Time-slots
-1 Time-slot = 0.5 ms (i.e 1 Sub-frame = 1 ms)
-1 Time-slot = 7 Modulation Symbols (when normal CP length is used)
-1 Modulation Symbols = 6 bits; if 64 QAM is used as modulation scheme
Radio resource is manage in LTE as resource grid....
-1 Resource Block (RB) = 12 Sub-carriers
Assume 20 MHz channel bandwidth (100 RBs), normal CP
Therefore, number of bits in a sub-frame
= 100RBs x 12 sub-carriers x 2 slots x 7 modulation symbols x 6 bits
= 100800 bits
Hence, data rate = 100800 bits / 1 ms = 100.8 Mbps
* If 4x4 MIMO is used, then the peak data rate would be 4 x 100.8 Mbps = 403 Mbps.
* If 3/4 coding is used to protect the data, we still get 0.75 x 403 Mbps = 302 Mbps as data rate.
29. 3G LTE specification overview (1/2)
WCDMA
(UMTS)
HSPA
HSDPA / HSUPA
HSPA+ LTE
Max downlink
speed
bps
384 k 14 M 28 M 100M
Max uplink speed
bps
128 k 5.7 M 11 M 50 M
Latency
round trip time
approx
150 ms 100 ms 50ms (max) ~10 ms
3GPP releases Rel 99/4 Rel 5 / 6 Rel 7 Rel 8
Approx years of
initial roll out
2003 / 4
2005 / 6 HSDPA
2007 / 8 HSUPA
2008 / 9 2009 / 10
Access
methodology
CDMA CDMA CDMA
OFDMA / SC-
FDMA
LTE can be seen for provide a further evolution of functionality, increased speeds
and general improved performance.
30. 3G LTE specification overview (2/2)
Parameter Details
Peak downlink speed
64QAM
(Mbps)
100 (SISO), 172 (2x2 MIMO), 326 (4x4 MIMO)
Peak uplink speeds
(Mbps)
50 (QPSK), 57 (16QAM), 86 (64QAM)
Data type
All packet switched data (voice and data). No circuit
switched.
Channel bandwidths
(MHz)
1.4, 3, 5, 10, 15, 20
Duplex schemes FDD and TDD
Mobility
0 - 15 km/h (optimised),
15 - 120 km/h (high performance)
Latency
Idle to active less than 100ms
Small packets ~10 ms
Spectral efficiency
Downlink: 3 - 4 times Rel 6 HSDPA
Uplink: 2 -3 x Rel 6 HSUPA
Access schemes
OFDMA (Downlink)
SC-FDMA (Uplink)
Modulation types supported QPSK, 16QAM, 64QAM (Uplink and downlink)
31. OFDM offers distinct advantages compared to
the CDMA technology
When compared to the CDMA technology upon which UMTS is based,
OFDM offers a number of distinct advantages:
⢠OFDM can easily be scaled up to wide channels that are more resistant
to fading.
⢠OFDM channel equalizers are much simpler to implement than are
CDMA equalizers, as the OFDM signal is represented in the frequency
domain rather than the time domain.
⢠OFDM can be made completely resistant to multi-path delay spread. This
is possible because the long symbols used for OFDM can be separated
by a guard interval known as the cyclic prefix (CP). The CP is a copy of
the end of a symbol inserted at the beginning. By sampling the received
signal at the optimum time, the receiver can remove the time domain
interference between adjacent symbols caused by multi-path delay
spread in the radio channel.
⢠OFDM is better suited to MIMO. The frequency domain representation of
the signal enables easy precoding to match the signal to the frequency
and phase characteristics of the multi-path radio channel.
32. OFDM does have some disadvantages
⢠The subcarriers are closely spaced making OFDM sensitive to frequency
errors and phase noise. For the same reason, OFDM is also sensitive to
Doppler shift, which causes interference between the subcarriers (ICI).
⢠Pure OFDM also creates high peak-to-average signals, and that is why a
modification of the technology called SC-FDMA is used in the uplink. SC-
FDMA is discussed later.
⢠It is known that OFDM will be more difficult to operate than CDMA at the
edge of cells. CDMA uses scrambling codes to provide protection from
inter-cell interference at the cell edge whereas OFDM has no such feature.
Therefore, some form of frequency planning at the cell edges will be
required.
33. ⢠LTE system information is one of the key aspects of the air interface. It consists of the Master Information Block
(MIB) and a number of System Information Blocks (SIBs). The MIB is broadcast on the Physical Broadcast Channel
(PBCH), while SIBs are sent on the Physical Downlink Shared Channel (PDSCH) through Radio Resource Control
(RRC) messages. SIB1 is carried by "SystemInformationBlockType 1" message. SIB2 and other SIBs are carried by
"SystemInformation (SI)" message. An SI message can contain one or several SIBs.
⢠1. The MIB is the first thing a UE looks for after it achieves downlink synchronization. The MIB carries the most
essential information that is needed for the UE to acquire other information from the cell. It includes:
⢠The downlink channel bandwidth
⢠The PHICH configuration. The Physical Hybrid ARQ Indicator Channel carries the HARQ ACKs and NACKs for uplink
transmissions
⢠The SFN (System Frame Number) which helps with synchronization and acts as a timing reference
⢠The eNB transmit antenna configuration specifying the number of transmit antennas at eNB such as 1, 2, or 4,
which is carried by CRC mask for PBCH
⢠2. SIB1 is carried in a SystemInformationBlockType1 message. It includes information related to UE cell access
and defines the schedules of other SIBs, such as:
⢠The PLMN Identities of the network
⢠The tracking area code (TAC) and cell ID
⢠The cell barring status, to indicate if a UE may camp on the cell or not
⢠q-RxLevMin, which indicates the minimum required Rx Level in the cell to fulfill the cell selection criteria
⢠The transmissions times and periodicities of other SIBs
LTE system information (1/3)
34. LTE system information (2/3)
⢠3. SIB2 contains radio resource configuration information common for all UEs, including:
⢠The uplink carrier frequency and the uplink channel bandwidth (in terms of the number of
Resource Blocks, for example n25, n50)
⢠The Random Access Channel (RACH) configuration, which helps a UE start the random access
procedure, such as preamble information, transmit time in terms of frame and subframe number
(prach-ConfigInfo), and powerRampingParameters which indicates the initial Tx power and
ramping step.
⢠The paging configuration, such as the paging cycle
⢠The uplink power control configuration, such as P0-NominalPUSCH/PUCCH
⢠The Sounding Reference Signal configuration
⢠The Physical Uplink Control Channel (PUCCH) configuration to support the transmission of
ACK/NACK, scheduling requests, and CQI reports
⢠The Physical Uplink Shared Channel (PUSCH) configuration, such as hopping
35. LTE system information (3/3)
⢠4. SIB3 contains information common for intra-frequency, inter-frequency, and/or inter-RAT
cell reselection. This information does not necessarily apply to all scenarios; please refer to
3GPP TS 36.304 for the details. The basic parameters include:
⢠s-IntraSearch: the threshold for starting intra-frequency measurement. When s-ServingCell
(i.e., cell selection criterion for serving cell) is higher than s-IntraSearch, the UE may choose
not to perform measurement in order to save battery life.
⢠s-NonIntraSearch: the threshold for starting inter-frequency and IRAT measurements
⢠q-RxLevMin: the minimum required Rx level in the cell
⢠Cell reselection priority: the absolute frequency priority for E-UTRAN or UTRAN or GERAN or
CDMA2000 HRPD or CDMA2000 1xRTT
⢠q-Hyst: the hysteresis value used for calculating the cell-ranking criteria for the serving cell,
based on RSRP.
⢠t-ReselectionEUTRA: the cell reselection timer value for EUTRA. t-ReselectionEUTRA and q-
Hyst can be configured to trigger cell reselection sooner or later.
⢠5. SIB4 contains the intra-frequency neighboring cell information for Intra-LTE intra-
frequency cell reselection, such as neighbor cell list, black cell list, and Physical Cell Identities
(PCIs) for Closed Subscriber Group (CSG). CSG can be used to support Home eNBs.
⢠6. SIB5 contains the neighbor cell related information for Intra-LTE inter-frequency cell-
reselection, such as neighbor cell list, carrier frequency, cell reselection priority, threshold used
by the UE when reselecting a higher/lower priority frequency than the current serving
frequency, etc.
⢠(Note that 3GPP states that LTE neighbor cell search is feasible without providing an explicit
neighbor list. Since the UE can do blind detection of neighbor cells in LTE, the broadcast of LTE
neighbor cells is optional.)
36. âRSRQ reporting rangeâ and âRSRQ relationship to Es/Iotâ
⢠âR4-081419_RSRQ_reporting_rangâ gives an idea on how to
calculate RSRQ and how to define RSRQ reporting range.
⢠âR4-103007_Relay RSRQ Reporting Rangeâ gives a relationship
between RSRQ and Ăs/Iot .
⢠After a simple manipulation from this contribution,
⢠RSRQ(dB) = 10*log10[Ăs/(12*(Ăs+Iot)]. The unit is in dB.
â (where RSRQ =[(N*RSRP)/RSSI], RSSI=12*N*(Ăs+Iot) and RSRP=Ăs. The unit is in Watts.)