GSM Phase 2+ Um Air Interface - 4 days

PUBLIC COURSES; 3-6 MARCH, 5-8 MAY

Day 1

GSM Spectrum allocation for PGSM, EGSM, GSM1800, GSM1900. Radio channels and radio channel numbering - ARFCN.
The spectrum and radio channel constraints of GSM, the 200kHz radio channel.
Optimising the radio channel, GMSK and voice encoding. The radio channel bit rate and the TCH information bit rate. The TCH bit rate after channel encoding and Um framing. The number of TCH's which will fit into the bit rate of the radio channel. Developments in raising the TCH bit rate - channel encoding leading to the CS 14.4kb/s TCH. EDGE. PDCH bit rates for GPRS, types of channel encoding.
Classifying the 8 TCH's of the Radio Channel
Numbering them -TN0-7, the TDMA structure of GSM. The Physical channel. Relationship of the 'burst' and TN. The period of the Um burst. The guard period. The Um frame period. Numbering of the frames. Structures of the normal, access, dummy and SCH/FCCH bursts. The purpose of the TSC. How the guard period defines the maximum radius of the GSM cell.
CS Logical channels
The importance of the BCCH carrier. The definition of the logical channel. Common channels and dedicated channels. The information content and functions of the FCCH, SCH, BCCH, EBCH, NCH, CCCH, PCH, AGCH, RACH, SDCCH, SACCH.
Types of TCH. The FACCH.
Structures of the CS logical channels on the BCCH carrier (and non-BCCH carriers)
The difficulty of representing the structures. 'Abstractions' used in the GSM specifications and textbooks.
The combined and non-combined CCH structures. The 51-frame control channel multiframe and the 26-frame TCH multiframe. Superframes and Hyperframes. Logical control channels 4 burst structure. Logical channel bit-rates. The RACH logical channel; its position in the combined and non-combined CCCH structure. The SDCCH/4 and SDCCH/8 configurations and the SACCH 102 frame multiframe.
Idle frames. How the MS uses these to confirm measurements of neighbour cells. The MS search mechanism when measuring neighbour cells.
The Paging Channel, how the MS selects a CCCH Group and how it selects a paging channel within that group.

Day 2

GPRS logical channel structures in the 51-frame multiframe, the PRACH, PCCCH, PAGCH,
PPCH, on the BCCH carrier. The 52-frame multiframe structure of PDCH's, PACCH, PDTCH combined with the 51-frame multiframe BCCH carrier.
GPRS logical channel structures in the 52-frame multiframe, the PBCCH channel, the PCCCH, PPCH, PRACH, PAGCH, PTCCH, PDTCH, PACCH and idle frames. The functions of the GPRS logical channels.
System Information, SI-1, 2, 2bis, 2ter, 3, 4, 5, 5bis, 5ter, 6, 7, 8, 9, 13. Information and control messages on the BCCH channel and SACCH for CS and GPRS working.
Packet System Information, the presence of the PBCCH, SI-3, SI-4, (SI-15), PSI-1, 2, 3, 3bis, 4, 5, 13 on the PBCCH and PACCH.
Operating Procedures GPRS (note that these GPRS operations overviews complete GPRS on this course. Hereafter only CS operations are considered. GPRS operations are covered in detail in the course 'GPRS OPERATIONS')
GPRS Attach, authentication and encryption overview
UL PDP context activation overview
DL PDP context activation overview
TBF, the function of USF, TFI, TLLI, PTMSI overview
GPRS operations arrow diagrams overview
Types of cell re-selection/measurement reporting/handovers used in GPRS.
Methods of power control and TA control.

Day 3

Operating Procedures CS
PLMN selection for CS and GPRS operations.
Cell selection for CS and GPRS operations - the C1 criterion.
Cell reselection for CS operations, the C2 criterion. The parameters for cell selection and reselection.
Cell reselection in GPRS operations,
The necessary conditions for GPRS cell reselection to be in operation. The criteria C1, C31 and c32 and the parameters controlling these criteria.
Accessing the network
CS Channel request and immediate assignment detailed procedures. Timing Advance. Authentication and encryption in the home and foreign PLMN's. LA updating procedures. IMSI Attach/detach procedures.
MO telephone call set up overview
MT telephone call set up overview.
MO SMS set up procedure overview.
MT SMS set up procedure overview.
VBS and CBCH operations overview.
VGCS operations overview.
CS Measurement Reports and Power Control
The parameters used and methods of measuring in the idle and active conditions. The effect of DTX on measurements. The relationship between BA_Lists on the BCCH and SACCH and the reported frequency.
CS Handovers
Types of handover, network parameters for imperative handovers, RXQUAL, RXLEVEL, IH, TAH.
Network parameters for power budget handovers.
Congestion relief handovers and directed retry handovers.

Detailed CS RR Information
The LAI, MCC, MNC, LAI, CI, CGI.
BSIC, NCC, BCC. Overcoming the limited BSIC allocation - an examination of the BSIC allocation in the 4/12-cell cluster and how this is now superseded with the problems that arise. How the MS discriminates between BCCH carriers. 'Borrowing' foreign NCC's.
RACH Control
The parameters of RACH control and how they are used.
Access Classes
The parameters to control access to a cell and the procedures used.
NCC permitted
The use of this function at international borders and to increase the BSIC allocation inside a country.
Configuring the CCCH's
Putting CCCH's on TNs other than BCCH TN0. Configuration parameters. Configuration of the CCCH's into PCH and AGCH. The parameters and their application. How the MS selects a CCCH and PCH. DRX. Paging modes, Paging types.
Neighbour Cell Lists
On the BCCH and SACCH. The BA bit-map. BA_IND, EXT_IND. How the MS uses the lists.
Radio Link Time-out
The operation and parameters of RLT on the UL and DL
DTX
The operation of DTX - why it is used. SACCH bursts and SID bursts. The significance of RXLEV_SUB and RXQUAL_SUB in measurement reports.
PWRC
When it should be used. Its significance when hopping into the BCCH carrier.

Day 4

The CS Protocol Layers and message flow
Protocol layers
Functions of the L1 physical, L2-LAPDm and L3 RR, MM, CM and 'application' layers
The A-bis and A interfaces.
Detailed message flow for registration, authentication, encryption, TMSI reallocation, MO telephone call set-up, and MT telephone call set-up. Detailed arrow diagrams.
Detailed message flow for handover with arrow diagrams.
Typical Layer 3 message structures.
L2 -LAPDm detailed functions, frame flow, timers, and frame types. Connection and Connectionless communication.
Frequency Hopping
Its advantages, the effect of Rayleigh fading, the interference averaging effect. Baseband and Synthesiser hopping. The constraints on hopping into BCCH control channels. The constraints on hopping into BCCH traffic channels when hopping over more frequencies than there are TRX's. Cyclic and PR hopping. How the MS uses the parameters CA, MA, HSN, TSC, MAIO. How hopping affects the BER and FER.
Channel Encoding and interleaving
Why it is done. How it is done. The block diagrams (not detailed descriptions) of FEC and block encoding.
Encoding and interleaving the TCH/FS
Encoding and interleaving the TCH/Data
Encoding and interleaving control channels
Encoding and interleaving the FACCH