Wednesday, May 19, 2010

Measurement report UMTS and LTE

Measurement report 3G

Two types of Measurement reporting is possible in 3G

1. Periodic

2. Event triggered

Measurement reporting parameters for both Periodic and Event triggered are set through system information.

Measurement report is send by the UE if a specific condition fulfilled.

To set the reporting condition, parameters are set in the system information 11 for idle state and system information 12 for connected state. If the parameters are not set in system information, it could be send through Measurement control.

Following are the different measurement reporting that UE can Perform:-

1. Intra-frequency measurements:

Parameter: - CPICH Ec/No, CPICH RSCP, pathloss

Event 1a:
A Primary CPICH enters the reporting range
Event 1b:
A Primary CPICH leaves the reporting range
Event 1c:
A non-active primary CPICH becomes better than an active primary CPICH
Event 1d:
Change of best cell
Event 1e:
A Primary CPICH becomes better than an absolute threshold
Event 1f:
A Primary CPICH becomes worse than an absolute threshold

2. Inter-frequency measurements:

Parameter :- CPICH Ec/No, CPICH RSCP

Event 2a:
Change of best frequency
Event 2b:
The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold.
Event 2c:
The estimated quality of a non-used frequency is above a certain threshold
Event 2d:
The estimated quality of the currently used frequency is below a certain threshold
Event 2e:
The estimated quality of a non-used frequency is below a certain threshold
Event 2f:
The estimated quality of the currently used frequency is above a certain threshold

3. Inter-RAT measurements:

Parameter: - GSM carrier RSSI

Event 3a:
The estimated quality of the currently used UTRAN frequency is below a certain threshold and the estimated quality of the other system is above a certain threshold.
Event 3b:
The estimated quality of other system is below a certain threshold
Event 3c:
The estimated quality of other system is above a certain threshold
Event 3d:
Change of best cell in other system

4. Traffic Volume Measurements

Parameter: - total buffer occupancy (BO) of RLC buffer, average of BOs, variance of BOs

Event 4a:
Transport Channel Traffic Volume becomes larger than an absolute threshold
Event 4b:
Transport Channel Traffic Volume becomes smaller than an absolute threshold

5. Quality measurements:

Parameter: - BLER (transport channel block error rate)

Event 5a:
A predefined number of bad CRCs are exceeded

6. UE internal measurements:

Parameter: - UTRA carrier RRSI (intra or interfrequency), UE Transmitted power, UE Rx-Tx Time difference

Event 6a:
The UE Tx power becomes larger than an absolute threshold
Event 6b:
The UE Tx power becomes less than an absolute threshold
Event 6c:
The UE Tx power reaches its minimum value
Event 6d:
The UE Tx power reaches its maximum value
Event 6e:
The UE RSSI reaches the UE's dynamic receiver range
Event 6f:
(FDD) The UE Rx-Tx time difference for a RL included in the active set becomes larger than an absolute threshold
(1.28 Mcps TDD): The time difference indicated by TADV becomes larger than an absolute threshold
Event 6g:
The UE Rx-Tx time difference for a RL included in the active set becomes less than an absolute threshold

7. Positioning measurements:

Parameter: - UE GPS timing, Synchronization measurements SFN-SFN, SFN-CFN, GSM carrier observed time difference

Event 7a:

The UE position changes more than an absolute threshold

Event 7b:

SFN-SFN measurement changes more than an absolute threshold

Event 7c:

GPS time and SFN time have drifted apart more than an absolute threshold

Event 7d: GANSS time and SFN time have drifted apart more than an absolute threshold

Measurement reports in LTE

1. Event A1 (Serving becomes better than threshold)

2. Event A2 (Serving becomes worse than threshold)

3. Event A3 (Neighbor becomes offset better than serving)

4. Event A4 (Neighbor becomes better than threshold)

5. Event A5 (Serving becomes worse than threshold1 and neighbor becomes better than threshold2)

6. Event B1 (Inter RAT neighbor becomes better than threshold)

7. Event B2 (Serving becomes worse than threshold1 and inter RAT neighbor becomes better than threshold2)

Measurement report UMTS and LTE comparison

LTE Measurement Events and Description

UMTS Measurement Events and Description

Comments

Event A1 - Serving becomes better than threshold

e2f - The estimated quality of the currently used frequency is above a certain threshold

In LTE this may be used to stop looking for a cell on a different frequency or technology, as e2f is used in UMTS.

Event A2 - Serving becomes worse than threshold

e2d - The estimated quality of the currently used frequency is below a certain threshold

In LTE this may be used to start looking for a cell on a different frequency or technology, as e2d is used in UMTS.

Event A3 - Neighbor becomes offset better than serving

e1a - A Primary CPICH enters the reporting range

This comparison is a bit of a stretch. The reason I have equated them is because in both cases a neighbor should be considered for a handover, either soft or hard depending on the technology.

Event A4 - Neighbor becomes better than threshold

e1e - A Primary CPICH becomes better than an absolute threshold

Event A5 - Serving becomes worse than threshold1 and neighbor becomes better than threshold2

e2b - The estimated quality of the currently used frequency is below a certain threshold and

the estimated quality of a non-used frequency is above a certain threshold

This comparison is good for saying that the current cell is below an absolute threshold and the new cell is above a threshold. This would mean that the current cell is not good enough and the new one is good, which is a good reason to do a hard handover (in either technology).

Event B1 - Inter RAT neighbor becomes better than threshold

e3c - The estimated quality of other system is above a certain threshold

Event B2 - Serving becomes worse than threshold1 and inter RAT neighbor becomes better than threshold2

e3a - The estimated quality of the currently used UTRAN frequency is below a certain

threshold and the estimated quality of the other system is above a certain threshold

This comparison is good for saying that the current cell is below an absolute threshold and the new cell on a different technology is above a threshold. This would mean that the current cell is not good enough and the new one is good, which is a good reason to do a hard handover to the new technology.

Monday, May 17, 2010

3GPP, ITU-T Important Specifications

3GPP, ITU-T Important Specifications

I.1. Introduction
Specification Number Specification Title
3GPP TR 21.900 Technical Specification Group working methods

I.2. Principles of WCDMA
3GPP TS 25.214 Physical layer procedures (FDD)
3GPP TS 25.401 UTRAN overall description

I.3. UMTS Network Architecture

3GPP TS 23.002 Network Architecture
3GPP TS 23.003 Numbering, addressing and identification
3GPP TS 23.101 General UMTS Architecture
3GPP TS 23.107 Quality of Service (QoS) concept and architecture

I.4. User Equipment

3GPP TS 27.001 General on Terminal Adaptation Functions (TAF) for Mobile Stations (MS)
3GPP TS 27.007 AT command set for 3G User Equipment (UE)
3GPP TS 31.101 UICC-terminal interface; Physical and logical characteristics
3GPP TS 31.111 USIM Application Toolkit (USAT)

I.5. Access Network

3GPP TS 23.002 Network Architecture
3GPP TS 25.301 Radio Interface Protocol Architecture
3GPP TS 25.331 Radio Resource Control (RRC) protocol specification
3GPP TS 25.401 UTRAN overall description
3GPP TS 25.413 UTRAN Iu interface RANAP signaling
3GPP TS 25.423 UTRAN Iur interface RNSAP signaling
3GPP TS 25.433 UTRAN Iub interface NBAP signaling

I.6. Core Network
3GPP TS 23.002 Network Architecture
3GPP TS 23.060 General Packet Radio Service (GPRS) Service description
3GPP TS 24.008 Mobile radio interface Layer 3 specification: Core Network protocols (Stage
3)
3GPP TS 29.002 Mobile Application Part (MAP) specification
3GPP TS 29.060 GPRS Tunnelling Protocol (GTP) across the Gn and Gp interface
ITU-T Q.714 Signaling Connection Control Part procedures
ITU-T Q.764 ISDN User Part signaling procedures
ITU-T Q.774 Transaction Capabilities procedures

I.7. Radio Resource Control Procedures

3GPP TS 25.331 Radio Resource Control (RRC) protocol specification

I.8. UTRAN Signaling Procedures
3GPP TS 25.401 UTRAN overall description
3GPP TR 25.931 UTRAN Functions, Examples on Signaling Procedures.

I.9. Mobility Management Procedures

3GPP TS 23.012 Location management procedures
3GPP TS 23.060 General Packet Radio Service (GPRS) Service description
3GPP TS 24.008 Mobile radio interface Layer 3 specification; Core network protocols

I.10. Call Handling Procedures

3GPP TS 23.018 Basic Call Handling

I.11. Session Management Procedures

3GPP TS 23.060 General Packet Radio Service (GPRS) Service description
3GPP TS 24.008 Mobile radio interface Layer 3 specification; Core network protocols

I.12. Supplementary Services

3GPP TS 22.004 General on Supplementary Services
3GPP TS 23.011 Technical Realization of Supplementary services – General Aspects

I.13. Value-added Services

3GPP TS 23.040 Technical realization of Short Message Service (SMS)
3GPP TS 23.041 Technical realization of Cell Broadcast Service (CBS)
3GPP TS 23.140 Multimedia Messaging Service (MMS); Functional description
3GPP TS 23.271 Location Services (LCS)

I.14. Security Related Procedures

3GPP TS 33.102 3G Security; Security Architecture
3GPP TS 33.200 Network Domain Security; MAP application layer security
3GPP TS 33.203 Access security for IP-based services
3GPP TS 33.210 Network Domain Security: IP network layer security

I.15. IP-Based Signaling Transport

3GPP TS 29.202 SS7 Signaling Transport in Core Network (Stage 3)
RFC 3332 SS7 MTP3 User Adaptation Layer (M3UA)
Internet Draft Signaling Connection Control Part User Adaptation Layer (SUA)
I.16. IP Multimedia Subsystem
3GPP TS 23.002 Network Architecture
3GPP TS 23.228 IP Multimedia Subsystem (Stage 2)
3GPP TS 24.229 IP Multimedia Call Control based on SIP and SDP
RFC 3261 SIP: Session Initiation Protocol

I.16. 3GPP UMTS architecture specs

3GPP TS 22.101: "Universal Mobile Telecommunications System (UMTS): Service aspects; Service principles".
3GPP TS 23.101: "Universal Mobile Telecommunications System (UMTS): General UMTS Architecture".
3GPP TS 23.105: "Universal Mobile Telecommunications System (UMTS): Network Principles".

I.17. Layer 1 Specs

3GPP TS 25.211: "Physical channels and mapping of transport channels onto physical channels (FDD)".
3GPP TS 25.212: "Multiplexing and channel coding (FDD)“
3GPP TS 25.213: "Spreading and modulation (FDD)“
3GPP TS 25.215: "Physical layer – Measurements (FDD)“
3GPP TS 25.101: "UE Radio transmission and Reception (FDD)“
3GPP TS 25.214: "Physical layer procedures (FDD)".
3GPP TS 25.302: "Services Provided by the Physical Layer".

I.18. Layer 2 Specs

3GPP TS 25.321: "Medium Access Control (MAC); protocol specification".
3GPP TS 25.322: "RLC Protocol Specification".
3GPP TS 25.323: “PDCP”
3GPP TS 25.324: “BMC”

What happen when 3G UE switch on...???








CELL SEARCH IN 3G: - Frequency and Time Synchronization in 3G


This procedure takes place when the power is turned on in the UE.
The synchronization procedure starts with downlink SCH synchronization.
The UE knows the SCH primary synchronization code, which is common to all cells.
The slot timing of the cell can be obtained by receiving the primary synchronization channel (P-SCH) and detecting peaks in the output of a filter that is matched to this universal synchronization code.
The slot synchronization takes advantage of the fact that the P-SCH is only sent during the first 256 chips of each slot. The whole slot is 2,560 chips long.
The UE can determine when a slot starts, but it does not know the slot number yet (there are 15 slots in each frame), and thus it does not know where the radio frame boundary may be.

Thereafter the UE correlates the received signal from the secondary synchronization channel (S-SCH) with all secondary synchronization codes (SSC), and identifies the maximum correlation value.
The S-SCH is also only sent during the first 256 chips of every slot.
Each code group identifies eight possible primary scrambling codes, and the correct one is found by correlating each candidate in turn over the CPICH of that cell.
Once the correct primary scrambling code has been identified, it can be used to decode BCH information from the primary common control physical channel (P-CCPCH), which is covered with the cell’s unique primary scrambling code.
The primary synchronization code is common to all cells, and it is used to gain slot synchronization from the P-SCH.
The primary scrambling code is unique to a cell; it is gained from the CPICH and used to demodulate common control channels

Saturday, May 15, 2010

3G Interview questions

1. Explain 3G?
2. What is 3GPP?
3. What is Generic Connection Framework (GCF )
4. Define FDMA TDMA,CDMA
5. Difference between CDMA and WCDMA
6. Difference between 3G and 2G
7. What is UMTS?
8. Difference between GERAN and UTRAN
9. what is Wcdma technology
10. 3GPP Specification for every layer
11. Benefit of spreading
12. Benefit of scrambling
13. What happen when Mobile switch on(Cell Search Procedure)
14. Mode of operations of RLC
15. Functions of RRC Layer
16. Functions of different MAC entities.
17. Information of all the system information
18. Channels and its mapping with different layers
19. What is channel
20. Role and architecture of RNC
21. How scrambling code is calculated
22. What are signaling radio bearer and there specific uses
23. Contents of Measurement control
24. Explain all seven Measurement reports
25. Differences between Rel99and HSDPA/HSUPA
26. What is Initial Direct Transfer
27. Explain the contents of Radio Bearer Reconfiguration. specify Dynamic and semi static part of Radio Bearer Reconfiguration
28. Explain soft , softer and Hard Handover
29. What is Compressed mode and why it is required
30. Explain HARQ and how it is different from ARQ


WCDMA (3G ) LTE (4G) Good Books

Introduction to 3G mobile communications

By Juha Korhonen

http://www.elib.hbi.ir/computer/networking/pdf/1580535070-Artech-Introduction%20to%203G%20Mobile%20Communications%202ed.pdf

WCDMA for UMTS: HSPA evolution and LTE

By Harri Holma, Antti Toskala

http://www.megaupload.com/?d=ST6EK1JM

HSDPA/HSUPA for UMTS: high speed radio access for mobile communications

By Harri Holma, Antti Toskala

http://iie.fing.edu.uy/~belza/Wiley.HSDPA.HSUPA.for.UMTS.High.Speed.Radio.Access.for.Mobile.Communications.ebook-Spy%282%29.pdf

LTE for UMTS - OFDMA and SC-FDMA Based Radio Access

By Harri Holma, Antti Toskala

http://rs381.rapidshare.com/files/269709821/LTE_for_UMTS_OFDMA_and_sc-FDMA_based_radio_Access.rar

LTE, The UMTS Long Term Evolution: From Theory to Practice

By Stefania Sesia, Issam Toufik, Matthew Baker

http://www.megaupload.com/?d=4LS45D4L

Evolved packet system (EPS): the LTE and SAE evolution of 3G UMTS

By Pierre Lescuyer, Thierry Lucidarme

LTE and the Evolution to 4G Wireless: Design and Measurement Challenges

By Moray Rumney


IF you don't find above books on the given link contact me wirless3g4g@gmail.com


Enjoy 3G 4G !!!!!!!!!!!!