Tele rf basic of drive test
- 1. 1 March 2013 Drive Testing Basics 2013
- 3. 3 Sector in Cell sites o Each Site is divided into sectors o Usually 3 sectors of 120 degree o Azimuth - It is the range covered by each sector , typically 120 degree for each sector Sector 1Sector 2Sector 3 azimuth
- 6. 6 2G 3G 4G 4G LTE 2G EDGE 9.6 kbps 120 kbps 384 kbps 1.5 Mbps 10 Mbps
- 7. 7 Signal travels in the form of Electromagnetic Wave or Frequency Spectrum and Frequency
- 8. 8 GSM 3G LTE Make sure that the Band is correctly configured Band Configurations
- 9. 9 GSM o Single Network for Both Voice and Data o Edge gives the data components o With GSM the speed was 9.6 Kbps o With Edge the speed goes to max 384 kbps o Practical Achievable speed is 120 Kbps Core Network
- 10. 10 UMTS (3G) o Two Separate networks o One provides Voice o Another Provides Data o Without HSPA upgrade the DL Speed is max up to 384 kbps o With HSPA the DL speed is average speed is up to 2 Mbps and Max is 15 mbps in DL
- 11. 11 LTE(4G) o Currently it is a data only network o Voice will come soon o The Voice will be on Internet just like your Vonage o Max Speed is 300 Mbps o Practical Speed is 10 to 15 Mbps
- 13. 13 Single Set of Antennas used for UMTS and LTE Shared Antennas
- 14. 14 LTE UMTS GSM
- 15. 15 DEDICATED MODE OR ON CALL MODE You are surfing internet
- 16. 16 IDLE MODE When you are not making a call or your phone is not updating Any apps or retrieving an email
- 19. 19 FALL BACK LTE 3G GSM CS FALL BACK For Voice Call on LTE Network
- 20. 20 IRAT LTE 3G GSM IRAT For Data Call on LTE Network
- 23. 23 Scanner UE Single Scanner for LTE , UMTS and GSM Separate Scanner for LTE and UMTS Acts independently of the network Scanner does not receive any commands From network Data Cards Mobile or Smart Phones Always receives commands from Network and acts accordingly Talks to the Network and tells it what is happening and then executes what network Decides
- 24. 24 -50 dBm -60 dBm -70 dBm -50 dBm -110 dBm Away from the site SIGNAL STRENGTH HOW STRONG THE SIGNAL IS
- 25. 25 SIGNAL QUALITY HOW CLEAN THE SIGNAL IS
- 26. 26 SIGNAL QUALITY As you go very far away from site not only does the strength reduce The quality also reduces GOOD AVERAGE BAD
- 27. 27 SIGNAL QUALITY Quality Problems Quality problems can occur close to the site or far away from the site
- 28. 28 Telecom Terminology GSM Rxlevel RxQual BCCH TCH UMTS(3G) RSCP Ec/Io PSC LTE(4G) RSRP RSRQ/SNR PCI Technology Received Signal level Received Signal quality Channels
- 29. 29 Good RF Condition GOOD RF CONDITIONS ARE DEFINED BY GOOD SIGNAL STRENGTH AND GOOD QUALITY GSM RSSI > -70dB UMTS RSCP > -70dB Ec/Io > -7dB LTE RSRP > -70dB SNR > 15dB
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- 31. 31 HANDOVER
- 32. 32 1 2 4 HANDOVER BETWEEN SECTORS OF THE SAME SITE THIS IS CALLED INTRA SITE HANDOVER 3
- 33. 33 1 2 3 4 HANDOVER BETWEEN SECTORS OF THE DIFFERENT SITE THIS IS CALLED INTER SITE HANDOVER
- 34. 34 Types of Drive Testing o Site Shakedown Single site based Drive and testing along the provided route Coverage footprint Each sector in the site is tested for throughput for uplink and downlink frequencies Hand overs intra/Inter Sites. I-Rat Handovers o Cluster Drive Multiple sites belonging to same location combined as cluster Provided drive routes that are supposed to be followed while driving and testing the network Additional tools used here would be MapInfo and Street Atlas Precautions to be taken: We need to ensure that the GPS is working Verify if the phone is locked for UMTS or LTE(follow market guidelines)
- 35. 35 Drive Route
- 36. 36 Typical Drive Test setup