Applied Wireless Electronics Grzegorz Budzyń Lecture Wireless data transfer GSM

Transcription

1 Applied Wireless Electronics Grzegorz Budzyń Lecture 7: Wireless data transfer GSM

2 WiFi- supplement GSM 2.5G+ standards HSCSD GPRS EDGE UMTS HSDPA HSUPA LTE Plan

3 WiFi - Supplement

4 WiFi new standards Theoldstandardscover80-90 % ofthe bandwidthdemandoftoday smobile applications New standardsenterthemarket: ac ad

5 WiFi ac Major features: Wider channels: Higher data rates up to 1.3Gbps per radio ac mandates support of 80MHz wide channels with optional 160MHz wide channels to achieve higher data rates than are achieved with n

6 WiFi ac Major features: Wider channels: Main disadvantage smaller number of available channels

7 WiFi ac Major features: Higher encoding density: Higher bit density per packet 256-QAM modulation used Increased number of spatial streams: Higher data rates per AP/client link Up to eight spatial streams, further increasing the data rate for each radio

8 WiFi ac Major features: Beamforming: Greater wireless AP/client link reliability Multi-user MIMO Greater AP/client capacity and efficient use of spectrum Supportssimultaneous transmissions to multiple clients and maximizes RF band utilization Up to four distinct clients can receive data simultaneously from a single AP at full channel data rate

9 WiFi ac Timetablefor commercialavailability

10 WiFi ad IEEE ad is an amendment to the WLAN standard which enables up to 7 Gbpsdata rates in the unlicensed and globally available 60 GHz band The 60 GHz band has wider channels, enabling higher data rates over short distances (1m 10m)

11 WiFi ad Mainapplications: RemovingwiresbetweenHigh-Definition multimedia, computer displays, I/O and peripheral, peer to peer data synchronization higher speed LAN

12 WiFi ad A shared MAC layer with existing networks enables session switching between networks operating in the 2.4 GHz, 5 GHz and 60 GHz bands The ad MAC layer has been extended: to include beamformingsupport address the 60 GHz specific aspects of channel access, synchronization, association, and authentication

13 GSM - Introduction

14 Cellular Network Base stations transmit to and receive from mobiles at the assigned spectrum Multiple base stations use the same spectrum (spectral reuse) The service area of each base station is called a cell Each mobile terminal is typically served by the closest base stations Handoff when terminals move

15 Cellular Network Generations It is useful to think of cellular Network/telephony in terms of generations: 0G: Briefcase-size mobile radio telephones 1G: Analog cellular telephony 2G: Digital cellular telephony 3G: High-speeddigital cellular telephony (including video telephony) 4G: IP-based anytime, anywhere voice, data, and multimedia telephony at fasterdata rates than 3G (to be deployed in )

16 GSM Services Voice, 3.1 khz Short Message Service (SMS) 1985 GSM standard that allows messages of at most 160 chars. (incl. spaces) to be sent between handsets and other stations Over 2.4 billion people use it; multi-billion $ industry General Packet Radio Service (GPRS) GSM upgrade that provides IP-based packet data transmission up to 114 kbps Users can simultaneously make calls and send data GPRS provides always on Internet access and the Multimedia Messaging Service (MMS) whereby users can send rich text, audio, video messages to each other Performance degrades as number of users increase GPRS is an example of 2.5G telephony 2G service similar to 3G

17 Data transfer in GSM The "data over cellular" bearer services are part of the Phase 2 implementation of GSM Thebasicdata transfer technologyiscalledcsd (Circuit Switched Data) A GSM network s data transfer facility allows the digital equivalent of modem transmissions -known as data streaming -at data speeds of up to 9,600 bits per second ingsm900 and14,400 bitsper secondin GSM1800 networks

18 GSM frequency slots

19 GSM Frequencies Originally designed on 900MHz range, now also available on 800MHz, 1800MHz and 1900 MHz ranges. Separate Uplink and Downlink frequencies One example channel on the 1800 MHz frequency band, where RF carriers are space every 200 MHz UPLINK FREQUENCIES DOWNLINK FREQUENCIES 1710 MHz 1785 MHz 1805 MHz 1880 MHz UPLINK AND DOWNLINK FREQUENCY SEPARATED BY 95MHZ

20 Data bursts Normal burst ModulationusedinGSM isgmsk -> 270kb/s

21 GSM Architecture

22 Data transfer in GSM

23 Data transfer in GSM Mobile telephony generation 2G 2.5G 3G Data transfer standard CSD HSCSD GPRS EDGE UMTS

24 Data transfer in GSM Mobile telephony generation 3.5G 4G Data transfer standard HSDPA HSUPA HSPA+ LTE LTE Advanced WiMAX

25 GSM 2.5G+ standards

26 HSCSD High-speed circuit-switched data (HSCSD), is an enhancement to circuit switched data (CSD), with data rates up to 57.6kbit/s Channel allocation is done in circuit-switched mode, as with CSD Higher speeds are achieved as a result of superior coding methods, and the ability to use multiple time slots to increase data throughput(upto 4 slots)

27 HSCSD Pro: Flexible bearer service (BS) for higher data rates up to 57.6kb/s(1800MHz) or 38.4kb/s (900MHz) Transparent and non-transparent bearer services Rate adaptation for several standard interfaces incl. X.30/V.110, V.24, etc.

28 HSCSD Cons Circuit-switched access, which is often inefficient for dataservices that are burstyin nature Higher call blocking probability due to multi-slot allocation Possible high cost of service as it competes with voice service for the same resources

29 GPRS

30 GPRS General packet radio service (GPRS) is a packet oriented mobile data service Itisavailablebothin2G and3g networks In 2G systems, GPRS provides data rates of kbit/second Allowsfor efficientuseofthebandwidth (statisticalmultiplexing) Circuitswitching& Packetswitchingcanbe usedinparallel

31 GPRS statistical multiplexing Source: [1]

32 GPRS - Features Constantconnectivity GPRS isanoverlaynetworkovergsm Billingbasedon volumeofdata transferred GPRS usesradio channel200khz widecarring 271kbps ofdata Thisisdividedinto8 slots34kbps each(14.4 kbpsaftercorrections) 8*14.4 = 114kbps

33 GPRS - Coding GMSK andchannelencoding based on a convolutionalcodeused Fourcodingschemes: CS-1 speed: 8.0 kb/s per slot CS-2 speed: 12.0 kb/s per slot CS-3 speed: 14.4 kb/s per slot CS-4 speed: 20.0 kb/s per slot

34 GPRS Terminals ClassA: MS supportssimultaneousoperationofgprs and GSM services ClassB: MS ableto register to bothservicesbut works onlyina chosenone ClassC: MS workseitheringprs oringsm mode

35 EDGE

36 EDGE Enhanced Data rates for GSM Evolution (EDGE) isfurtherimprovementofdata transmissioningsm networks Packetswitchedtechnology Maindifferencecomparingto GPRS isthe changeofmodulationtechnology: from GMSK to 8PSK Performance sensitiveto radio conditions

37 Influence of EDGE on the GSM network structure

38 EDGE - modulation Source: [3]

39 EDGE - performance Source: [3]

40 UMTS

41 UMTS UMTS -UniversalMobile TelecommunicationsSystem ispart of3g and4g systems Unlikepreviouslydescribedtechniques UMTS requiresnew base stations and new frequency allocations UMTS networkisverysimilarto GSM The most common form of UMTS uses W- CDMAbut also TD-CDMAandTD-SCDMA

42 UMTS Network architecture RNC Radio Network Controller

43 UMTS modes UMTS worksintwomodes UMTS FDDor UMTS-TDD In bothmodesthereareused: CDMA QPSK modulation Multiple channel coding and bearer rates Asynchronous operation Data rateupto 2 Mbps

44 UMTS - Features Full packet driven architecture For voice and data transmission Packet based networks allow for an increased amount oftrafficon a medium Theonlytimethatpart ofthemedium isblockedis during transmission/reception Services

45 UMTS - Features UMTSsupports maximum theoretical data transfer rates of 42 Mbit/s(with HSPA+) At the moment users in deployed networks can expect a transfer rate of up to 384 kbit/s for R99 handsets, and 7.2 Mbit/sfor HSDPA handsets in the downlink connection

46 UMTS - Features Data ratesoverradio interface: 2Mbps in fixed or in-building environments 384kbps in pedestrian or urban environments 144kbps in wide area mobile environments Variable data rates in large geographic area systems(satellites)

47 UMTS Data rates Source: [3]

48 HSPA

49 HSDPA HSDPA -High-SpeedDownlinkPacketAccess -is an enhanced 3G (third generation) mobile telephony communications protocol in the High-Speed Packet Access (HSPA) family HSDPA allowsfor higherdata ratesinumts networks Current HSDPA deployments support downlink speeds of 1.8, 3.6, 7.2 and 14.0 Mbit/s

50 HSDPA The first phase of HSDPA has been specified in the 3rd Generation Partnership Project (3GPP) release 5: Upto 14Mbps The second phase of HSDPA is specified in the 3GPP release 7 and has been named HSPA Evolved: Upto 42Mbps MIMO

51 HSDPA Source: [1]

52 HSDPA - Features Fast downstreamthroughput: Data ratesupto 10 Mbps Peakdata rateseven14mbps, withmimo even ~20Mbps Significantcapacityincrease(vsUMTS): 3-4 times improved system capacity 1-2 times improvement for best-effort packet data Improved capacity for streaming services(50%)

53 HSDPA How it is done Adaptingto environment withadaptive modualtionandcoding Fast channelschedulingwithfastquality feedback MIMO Fast retransmissions Higherorder modulations(qpsk+16qam) Moreefficientprocessing

54 HSDPA Categories

55 HSUPA HSUPA -High-SpeedUplinkPacketAccess -is an enhanced 3G (third generation) mobile telephony communications protocol in the High-Speed Packet Access (HSPA) family HSUPA allowsfor higherdata ratesinumts networks Current HSUPA deployments support up-link speeds upto 5.76Mbit/s Works similarto HSDPA but inuplink direction

56 HSPA+ HSPA -EvolvedHigh-Speed Packet Access (HSPA) family Providesprovides HSPA data rates up to 56 Mbit/son the downlink and 22 Mbit/son the uplink with MIMO technologies and higher order modulation (64QAM) The 56 Mbit/sand 22 Mbit/srepresent theoretical peak sector speeds. The actual speed for a user will be lower

57 HSPA+ Mainenhancementsincomparisonto HSPA: 64QAM indl with(1x2) SIMO 16QAM indl with(2x2) MIMO 16QAM inul 64QAM indl with(2x2) MIMO

58 HSPA+ vs WiMAX

59 HSPA+ vs WiMAX Source: [4]

60 LTE

61 Comparison of LTE Speed

62 LTE LTE -LongTerm Evolution-is the latest standard in the mobile network technology tree TheLTE baseson a anotherradio interfacethan GSM/UMTS networks Uses Orthogonal Frequency Division Multiplexing (OFDM) for downlink Uses Single Carrier Frequency Division Multiple Access (SC-FDMA) for uplink Uses Multi-input Multi-output(MIMO) for enhanced throughput

63 LTE

64 High spectral efficiency LTE - features OFDM in Downlink, Robust against multipathinterference & High affinity to advanced techniques such as Frequency domain channeldependent scheduling & MIMO DFTS-OFDM ( Single-Carrier FDMA ) in Uplink, Low PAPR, User orthogonalityin frequency domain Multi-antenna application Very low latency Short setup time & Short transfer delay Support of variable bandwidth 1.4, 3, 5, 10, 15 and 20 MHz

65 Advantages of LTE

66 LTE Major Parameters

67 LTE User Equipement Categories

68 LTE Advanced

69 LTE vs LTE Advanced

70 LTE Advanced LTE Advanced evolutionoflte towards improved data bandwidth LTE Advanced 3GPP projectreleases10 and beyond Finalizedby 3GPP in March 2011 LTE Advanced is backward compatible with LTE 100MHz aggregated bandwidth 3.3Gbitpeak download rates per sector of the base station under ideal conditions

71 LTE Advanced - features Coordinated multipoint(comp) transmission and reception UE Dual TX antennasolutionsfor SU-MIMO and diversitymimo Scalablesystem bandwidthexceeding20mhz, upto 100MHz Carrier aggregation of contiguous and noncontiguous spectrum allocations Flexible spectrum usage Cognitiveradio

72 LTE Advanced - features Automatic and autonomous network configuration and operation Support of autonomous network and device test, measurement tied to network management and optimization Enhanced precoding and forward error correction Interference management and suppression Asymmetric bandwidth assignment for FDD HybridOFDMA andsc-fdmainuplink SONs, Self Organized Networks methodologies Multiple carrier spectrum access.

73 Application example

74 Application example

75

76 GSM module - features Tri-band GSM/GPRS SMT module Size33x33x3 mm! An embedded TCP/IP protocol stack Controlvia AT command Supplyvoltage V Data rates: GPRS: 85.6 kbpsindownlink CSD upto 14.4 kbps Many interfaces: SPI, GPIO, antena, SIM card, serial interface, 2 x analog audio interface

77 Thank you for your attention

78 [1] References [2] Lundmark T., WiMAX- a sneak preview, TietoEnator [3] MichaudF., GPRS & EDGE «FirststepstowardWirelessdata» [4] SridharIyer, WiMAX: IEEE WirelessMANs, [5] [6] [7] [8] 57%20UMTS-protocols%20and%20architecture.pdf [9]