Bsspar1 s14 chapter 02_radio_resource_administration_v1.1

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Bsspar1 s14 chapter 02_radio_resource_administration_v1.1

  1. 1. 1 © Nokia Siemens Networks BSSPAR1: Chapter 2 Radio Resource Administration
  2. 2. 2 © Nokia Siemens Networks Legal Notice Intellectual Property Rights All copyrights and intellectual property rights for Nokia Siemens Networks training documentation, product documentation and slide presentation material, all of which are forthwith known as Nokia Siemens Networks training material, are the exclusive property of Nokia Siemens Networks . Nokia Siemens Networks owns the rights to copying, modification, translation, adaptation or derivatives including any improvements or developments. Nokia Siemens Networks has the sole right to copy, distribute, amend, modify, develop, license, sublicense, sell, transfer and assign the Nokia Siemens Networks training material. Individuals can use the Nokia Siemens Networks training material for their own personal self-development only, those same individuals cannot subsequently pass on that same Intellectual Property to others without the prior written agreement of Nokia Siemens Networks . The Nokia Siemens Networks training material cannot be used outside of an agreed Nokia Siemens Networks training session for development of groups without the prior written agreement of Nokia Siemens Networks.
  3. 3. 3 © Nokia Siemens Networks Module Objectives • Give an overview about the TDMA frame structure • Describe the logical channels, their mapping to TDMA frames and their parameters • Demonstrate, how the signalling capacity effect the mapping of the logical channels • Describe the purpose of the Base Station Identity Code and the Training Sequence Code • Explain the use of frequency reuse and the fundamentals of frequency hopping • Discuss the parameter settings required for base band and RF frequency hopping
  4. 4. 4 © Nokia Siemens Networks TDMA frame = 8 timeslots ( 0.577ms * 8 = 4.615 ms) 0 1 3 4 5 7 6 0 1 2 3 4 5 7 6 0 1 2 3 4 5 200 kHz Physical channel e.g. allocated to one subscriber with FR voice and no frequency hopping frequency time TDMA frame 2 2 2 2 Basic TDMA Structure
  5. 5. 5 © Nokia Siemens Networks 0 1 2 49 500 1 2 24 25 0 2047 0 1 2 48 49 50 0 1 24 25 0 7 2048 super frames = hyper frame Super frame = 26 x (51 multi frame) or 51 x (26 multi frame) 26 multi frame = 120 ms 51 multi frame = 235 ms TDMA frame = 4.615 ms TDMA frame numbering 0 1 2 49 50 Multi, Super & Hyper Frames (Traffic and associated signalling) (Signalling and Control channels)
  6. 6. 6 © Nokia Siemens Networks Base Station Subsystem Logical Channels for transport of specific content Physical Channels transport medium MS mapping Physical channel parameters ARFCN Time slot number Frequency hopping algorithm GSM Channel Organization
  7. 7. 7 © Nokia Siemens Networks SCH FCCH PCH BCCH AGCH RACH SDCCH SACCH FACCH Stand alone Dedicated Control Channel Frequency Correction Channel Synchronisation Channel Broadcast Control Channel Paging Channel Slow Associated Control Channel Fast Associated Control Channel Paging Channel Random Access Channel Access Grant Channel BCH CCCH DCCH TCH DL DL DL UL Common Channels Dedicated Channels UL/DL UL/DL CBCH Cell Broadcast Channel Logical Channels FR/HR Full rate / Halft rate TCH EFR Enhanced Full rate TCH AMR FR/HR Adaptive multirate TCH (FR/HR)
  8. 8. 8 © Nokia Siemens Networks ... 26 TDMA frames = 120 ms 1 26 t t tt t t t ft tt t t tt t t tt ft t t ttts i Full Rate Traffic Channel Configuration (UL & DL) Half Rate Traffic Channel Configuration (UL & DL) 26 TDMA frames = 120 ms 1 26 t T T t t T t f t t T T T T t t T t T f T t T tt T s S t = full rate TCH, s = SACCH/T, i = idle TDMA frame t = half rate TCH, s = SACCH/T (first user) T = half rate TCH, S = SACCH/T (second user) TDMA frame Traffic Channel Mapping
  9. 9. 9 © Nokia Siemens Networks f s ff s f s Downlink 51 TDMA frames = 235 ms - Uplink BCCH CCCH f s f s CCCH CCCH SDCCH 0 SDCCH 1 SDCCH 2 SDCCH 3 SACCH 0/2 SACCH 1/3 r r f r r rr r r r fr r r r r rr r r r fr r r r rr f r r 1 51 SACCH 2/0 SACCH 3/1 SDCCH 0 SDCCH 1SDCCH 3 SDCCH 2 f = FCCH, s = SCH, r = RACH TDMA frame - = dummy burst 51 TDMA frames = 235 ms 1 51 Signalling Channel Mapping (BCCH + SDCCH/4 + SACCH/C4)
  10. 10. 10 © Nokia Siemens Networks f s ff s f s Downlink 51 TDMA frames = 235 ms - Uplink BCCH CCCH f s f s CCCH CCCH r r f r r rr r r r fr r r r r rr r r r fr r r r rr f r r 1 51 CCCH CCCH CCCH CCCH CCCH CCCH r rr r rr r r r r r r rr r r r r rr rr r r f = FCCH, s = SCH, r = RACH TDMA frame - = dummy burst 51 TDMA frames = 235 ms 1 51 Signalling Channel Mapping (BCCH +CCCH/9)
  11. 11. 11 © Nokia Siemens Networks f f i = idle TDMA frame f 51 TDMA frames = 235 ms iii iii SDCCH 0 SDCCH 1 SDCCH 2 SDCCH 3 SDCCH 4 SDCCH 5 SDCCH 6 SDCCH 7 SDCCH 1 SDCCH 2 SDCCH 3 SDCCH 4 SDCCH 5 SDCCH 6 SDCCH 7 SDCCH 0 Downlink Uplink SACCH 0/4 SACCH 1/5 SACCH 2/6 SACCH 3/7 SACCH 6/2 SACCH 7/3 SACCH 4/0SACCH 5/1 51 TDMA frames = 235 ms 1 51 1 51 Signalling Channel Mapping (SDCCH/8 +SACCH/C4)
  12. 12. 12 © Nokia Siemens Networks Channel configuration defined by parameter channelType TCHF (0) = full rate traffic channel TCHH (1) = half rate traffic channel TCHD (2) = dual rate traffic channel SDCCH (3) = standalone (SDCCH/8) MBCCH (4) = broadcast control channel MBCCHC (5) = BCCH + SDCCH/4 MBCCB (7) = BCCH + SDCCH/3 with CBCH SDCCB (8) = SDCCH/7 with CBCH NOTUSED (9) = timeslot has no radio definition or Abis allocation ERACH (10) = random access channel of extended area EGTCH (14) = EGPRS packed data traffic channel for extended area LRTCH (15) = long reach traffic channel Channel Mapping Parameter Setting Note: • Some values not allowed in certain tsl (e.g. TSL0 can’t have value 8) • PBCCH is not supported in S13 and onwards MO Class TR/RTSL Parameter channelxType (CHx) where x = 0…7
  13. 13. 13 © Nokia Siemens Networks When static SDCCHs overbooked  Free TCHs used for SDCCH traffic Rules for dynamic SDCCH allocation: • SDCCH is configured to TRX with least number of SDCCHs or no SDCCHs yet at all • SDCCH is configured to TRX with least number of occupied channels • If between different types of TCHs must be selected, the preference order is: HR, FR, DR TCH • DFCA: SDCCH and Dynamic SDCCH not supported on DFCA TRXs (only on regular TRX) Exceptions: • Configuration of any dynamic SDCCH resource in the BTS not possible • Only one TCH of the BTS is available Dynamic SDCCH allocation + FACCH call set up enabled simultaneously  dynamic SDCCH allocation has higher priority Dynamic SDCCH Allocation
  14. 14. 14 © Nokia Siemens Networks S13 Feature (Licence Based) • Up to 24 SDCCH channels for a BCCH TRX, • Up to 32 SDCCH channels for a non-BCCH TRX • Only supported by Ultrasite & Flexi BTS Dynamic SDCCH must be activated in the BSC before Increased Dynamic SDCCH Capacity can be activated. TRXSIG of 64kbps is required for the feature Increased Dynamic SDCCH Allocation BSS21113
  15. 15. 15 © Nokia Siemens Networks Alternative to dynamic SDCCH allocation (for call setup case) • Assignment of TCH to MS from CCCH instead of SDCCH • Call set up on FACCH instead on SDCCH Parameters (SEG Level) newEstabCausesSupport (NECI) Y/N Enables feature is general Parameters (BSC level) ordinaryCallOnFacch (EOF) Y/N Enables ordinary call set up on FACCH emerCallOnFacch (EEF) Y/N Enables emergency call set up on FACCH reestablishOnFacch (ERF) Y/N Enables call reestablishment on FACCH pagingAnsOnFacch (EPF) Y/N Enables answer to paging call setup on FACCH FACCH Call Set Up
  16. 16. 16 © Nokia Siemens Networks Mobile terminating call -> MSC performs paging MS identifies paging message with the IMSI/TMSI MS listens to own paging group only SEG-BTS parameters MSC parameters Repaging Interval (INT) 0.5s…10s Time between consecutive paging attempts Repaging Attempts (AT) 0…5 Number of paging repetitions Buffering BTS stores up to 8 paging messages of the MSC in page group buffer BTS sends paging messages to MS according noOfMultiframesBetweenPaging Paging Channel (PCH) Parameters MO Class Abbreviated Name Range And Step Description Default value BSC - MML Name BTS noOfMFramesB etweenPaging 2...9, step 1 Defines the number of multiframes between two transmissions of the same paging message to the MSs of the same paging group. 4 MFR
  17. 17. 17 © Nokia Siemens Networks Mobile sends channel requests to BTS separated by random time intervals in case of no answer! Parameters Random time interval between consecutive retransmissions t = S + random [0,.. numberOfSlotsSpreadTrans – 1] RACH slots S depends on numberOfSlotsSpreadTrans signalling channel mapping (CCCH + SDCCH combined or not in one multi frame) numberOfSlotsSpreadTrans = 10 signalling channel mapping = not combined  S = 58 Therefore t = 58..to..67 RACH slots time channel requests RACH Parameters MO Class Abbreviated Name Range And Step Description Default value BSC - MML Name BTS maxNumberRetra nsmission 1,2,4,7 Maximum number of retransmissions on the RACH that the MS can perform. 4 RET BTS nbrOfSlotsSpread Trans MML Range: 3..12, 14, 16, 20, 25, 32, 50 The number of TDMA frames over which retransmission is spread on the RACH (random access channel) 10 SLO
  18. 18. 18 © Nokia Siemens Networks Network gives the MS dedicated resources Downlink CCCH blocks • PCH can be used for AGCH messages • AGCH cannot be used for PCH messages Reservation of CCCH blocks for AGCH noOfBlocksForAccessGrant (AG) 0..7 possible number, if CCCH and SDCCH are not combined 1..7 possible number, if CBCH is used in non combined configuration 0..2 possible number, if CCCH and SDCCH are combined Preference of AGCH messages on PCH noOfBlocksForAccessGrant ≠ 0 PCH can be used only, if no paging messages have to be send = 0 AGCH messages have higher priority than PCH ones Number of paging groups N = (number of CCCH blocks – noOfBlocksForAccessGrant) * noOfMultiframesBetweenPaging AGCH Parameters
  19. 19. 19 © Nokia Siemens Networks Chs 1% 2% 3% 5% Chs 1% 2% 3% 5% 1 0.01 0.02 0.03 0.05 21 12.80 14.00 14.90 16.20 2 0.15 0.22 0.28 0.38 22 13.70 14.90 15.80 17.10 3 0.46 0.60 0.72 0.90 23 14.50 15.80 16.70 18.10 4 0.87 1.09 1.26 1.52 24 15.30 16.60 17.60 19.00 5 1.36 1.66 1.88 2.22 25 16.10 17.50 18.50 20.00 6 1.91 2.28 2.54 2.96 26 17.00 18.40 19.40 20.90 7 2.50 2.94 3.25 3.75 27 17.80 19.30 20.30 21.90 8 3.13 3.63 3.99 4.54 28 18.60 20.20 21.20 22.90 9 3.78 4.34 4.75 5.37 29 19.50 21.00 22.10 23.80 10 4.46 5.08 5.53 6.22 30 20.30 21.90 23.10 24.80 11 5.16 5.84 6.33 7.08 31 21.20 22.80 24.00 25.80 12 5.88 6.61 7.14 7.95 32 22.00 23.70 24.90 26.70 13 6.61 7.40 7.97 8.83 33 22.90 24.60 25.80 27.70 14 7.35 8.20 8.80 9.73 34 23.80 25.50 26.80 28.70 15 8.11 9.01 9.65 10.60 35 24.60 26.40 27.70 29.70 16 8.88 9.83 10.50 11.50 36 25.50 27.30 28.60 30.70 17 9.65 10.70 11.40 12.50 37 26.40 28.30 29.60 31.60 18 10.40 11.50 12.20 13.40 38 27.30 29.20 30.50 32.60 19 11.20 12.30 13.10 14.30 39 28.10 30.10 31.50 33.60 20 12.00 13.20 14.00 15.20 40 29.00 31.00 32.40 34.60 Erlang B Table For reference in upcoming calculations
  20. 20. 20 © Nokia Siemens Networks Combined CCCH / SDCCH configuration noOfBlocksForAccessGrant = 1  2 CCCH blocks for PCH 3 MSs paged per paging message  3 pages per block 2 blocks per multi frame  3 * 2 = 6 pages per multiframe Number of pages per hour  3600 s / 0.235 s * 6 = 91915 Avg of 2 pages required per MS  91915 / 2 = 45957 MSs per hour BTS 3 MS Paging_Request BTS 3 MS Paging_Request Paging Capacity Example
  21. 21. 21 © Nokia Siemens Networks Cell with 325 subscribers 1 call per subscriber once in a hour 1 location update (LU) per subscriber once in 2 hours Duration of call assignment = 4 s  4 s / 3600 s = 1.11 mErl on SDCCH per subscriber 325 subscribers  325 * 1.11 mErl = 0.3607 Erl on SDCCH Reservation time for LU = 5s 5 s / 7200 s = 0.69 mErl on SDCCH per subscriber 325 subscribers  0.2242 Erl on SDCCH Total SDCCH traffic  0.3607 Erl + 0.2242 Erl = 0.5849 Erl Blocking probability = 1%  4 SDCCHs required  SDCCH combined with CCCH can be used (MBCCHC) SDCCH Signalling Capacity Example with call Establishment & Location Update
  22. 22. 22 © Nokia Siemens Networks Same cell with 325 subscribers Additional SMS traffic of 1 mErl per subscriber 325 subscribers  325 * 1 mErl = 0.325 Erl on SDCCH Total SDCCH traffic  0.5849 + 0.325 Erl = 0.9099 Erl Blocking probability = 1%  5 SDCCHs required  not combined with CCCH (MBCCH) SDCCH Signalling Capacity Example including SMS
  23. 23. 23 © Nokia Siemens Networks Base Station Identity Code BSIC = Network Colour Code NCC + Base Station Colour Code BCC bsIdentityCode Setting of BSIC NCC 0..7, distinguishes between PLMNs BCC 0..7, distinguishes between clusters BSIC + frequency channel  unique identity of adjacent cell f1 f2 f3 f1 f1 bcc = 1 bcc = 2 bcc = 3 Base Station Identity Code
  24. 24. 24 © Nokia Siemens Networks Training Sequence Code (TSC) 0…7 Defined on TRX level Used to determine signal distortion and bit error rate training sequence encrypted bitsencrypted bits3 31 stealing flag stealing flag 57 bits 57 bits26 bits 1 tail bits tail bits Burst on TCH data± difference =difference expected burst training sequence ?? received burst correlation data* data*training sequence* data* Training Sequence Code
  25. 25. 25 © Nokia Siemens Networks 200 kHz 890 915 935 960 1 2 3 4 124123 1 2 3 4 124123 duplex distance Absolute radio frequency carrier number ARFCN uplink direction downlink direction Example: GSM 900 Defining Frequency carrier number
  26. 26. 26 © Nokia Siemens Networks Frequency to be used by TRX (must be unique within a BTS) initialFrequency (FREQ) 1…1023 Setting of ARFCNs GSM 800: 128 .. 251 GSM 900: 1..124 and 975..1023, 0 GSM 1800: 512..885 GSM 1900: 512..810 f1 f2 f3 f4 f5 f6 f7 f1 f2 f3 f4 f5 f6 f7 f1 f2 f3 f4 f5 f6 f7 Frequency Reuse
  27. 27. 27 © Nokia Siemens Networks Defining BA list bCCHAllocationList ID 1…2000 Indicates ARFCN values given by BCCH allocation list frequencyBandinUse 800, 900, 1800, 1900, Multi Frequency list of ARFCN in the BAL Idle mode  MS listens on BCCH idleStateBCCHAllocation (IDLE) 0,1…2000 0 = MS gets frequency information from adjacent cells defined for the BTS 1..2000 = MS gets frequency information from the defined BCCH allocation list Dedicated mode  MS listens on SACCH measurementBCCHAllocation (ACT) ADJ = MS gets frequency information from adjacent cells defined for the BTS IDLE = active MS uses same BCCH freq list as idle MS Frequency Information for MS
  28. 28. 28 © Nokia Siemens Networks Frequency Time F1 F2 F3 Call is transmitted through several frequencies to • average the interference (interference diversity) • minimise the impact of fading (frequency diversity) Frequency hopping techniques hoppingMode (HOP) BB,RF,N BB = base band hopping (1) RF = RF hopping (2) N = no frequency hopping at all (0) Principle of Frequency Hopping
  29. 29. 29 © Nokia Siemens Networks Baseband Hopping TRX 1 TRX 2 TRX 3 0 1 72 Timeslot TRX 4 BC CH f 1 f 2 f 3 f 4 HSN1 (BB hopping group 1 and RF hopping) Timeslot 0 hops over TRXs 2-4 only BCCH does not hop HSN2 (BB hopping group 2) Timeslots 1-7 hop over all TRXs TRXs do not hop Physical channels moved from one TRX to another Hopping sequence hoppingSequenceNumber (HSN) 0..63 0 = cyclic hopping 1..63 = pseudorandom hopping Base Band Hopping
  30. 30. 30 © Nokia Siemens Networks RF Hopping Standard technique TRX 1 TRX 2 TRX 3 0 1 72 Timeslot TRX 4 BC CH f1 – no hopping f2,f3..fn – hopping according mobile allocation list One hopping sequence number only All TRXs hop except TRX1 (provides BCCH) Up to 63 frequencies available defined by mobile allocation list -> better hopping gain mobileAllocationList Setting of ARFCN values usedMobileAllocation (MAL) 0,1...2000 0 = BTS detached from any list 1..2000 = indicates list which shall be used
  31. 31. 31 © Nokia Siemens Networks Standard technique 9 hopping hopping frequencies MAI = 0..8 But 3 frequencies available for every TRX only Freeform hopping For every sector same mobile allocation list hopping sequence number frame number (frame synchronization) For every sector different starting points for hopping sequence possible by mobile allocation index offset maioOffset (MO) 0..62 setting of MAIO 9 hopping hopping frequencies MAI = 0..8 9 frequencies available for every TRX RF Hopping Freeform Hopping MAIO Offset MAI TRX-1 (BCCH) - TRX-2 0 TRX-3 1 TRX-4 2 TRX-5 (BCCH) - TRX-6 3 TRX-7 4 TRX-8 5 TRX-9 (BCCH) - TRX-10 6 TRX-11 7 TRX-12 8 Sector-3 6 Sector-1 0 Sector-2 3
  32. 32. 32 © Nokia Siemens Networks Freeform hopping • Not adequate for MA list with consecutive ARFCN values • Avoids co-channel interference but not adjacent channel interference Flexible MAIO management MAIO increases with constant step size from one TRX to the next one maioStep (MS) 1..62 maioOffset = 0, 6, 12 for sector 1, 2, 3 maioStep = 2 18 frequencies required (2 * number of hopping TRXs) RF Hopping Flexible MAIO Management MAIO Offset MAIO Step MAI TRX-1 (BCCH) - TRX-2 0 TRX-3 2 TRX-4 4 TRX-5 (BCCH) - TRX-6 6 TRX-7 8 TRX-8 10 TRX-9 (BCCH) - TRX-10 12 TRX-11 14 TRX-12 16 Sector-3 2 0 6 12 Sector-1 2 Sector-2 2
  33. 33. 33 © Nokia Siemens Networks BCCH Band allocation: MA list Consecutive ARFCN Only BCCH frequency planning required Only BCCH frequency planning required Flexible MAIO management MAIO Offset + MAIO Step BCCH Band allocation: MA list Non-adjacent ARFCN Freeform hopping MAIO Offset MA list and BCCH frequency planning required MA list and BCCH frequency planning required RF Hopping (Tight Frequency Reuse)
  34. 34. 34 © Nokia Siemens Networks Changing Frequency Plan BSIC / TSC Frequencies Frequency hopping setting Intelligent underlay overlay TRX settings • Plan downloaded to BSC/BTSs via MML or GUI • File-based plan provisioning • Immediate Plan activation method

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