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Figure 5Curves illustrating maximum datathroughput for MCS-4 and MCS-9 versusC/l.Figure 6Carrier throughput and spectral efficiencyfor three different frequency-reuse patterns.EDGE radio-link performanceEDGE radio-link performance has beenevaluated extensively by ETSI and UWCC.Figure 5 shows the throughput for onetimeslot as a function of the carrier-tointerferenceratio (C/I). The throughput isobtained from simulations of the IR LQCscheme. This radio-link simulation createsthe basis for all subsequent system simulationsdescribed in this article.Static system-level simulationsFigure 6 shows the maximum performanceof EDGE packet traffic channels for differ-ent frequency-reuse patterns (maximum inthe sense that channel utilization is 100%and all 8 TS are used for traffic). The resultsare based on static system-level simulationsand the radio-link simulations mentionedabove. As expected, a tighter frequencyreusepattern with higher interference reducesmean throughput per carrier. What isinteresting, however, is that the spectral efficiencyof EDGE increases with tighter frequencyreuse (that is, the smaller bandwidthrequired by tighter frequency reuse outweighsthe reduction in throughput). Thisconfirms EDGE's capacity to perform wellin situations characterized by high interference,such as in a 1/3 frequency-reuse pattern.One way of analyzing the system performanceof a packet-data network is to studythe average throughput per carrier. Figure7 shows the impact of channel utilization(traffic intensity) on this metric on the firstcarrier. The results are based on static system-levelsimulations and the radio-linksimulations described above, with 7 TS usedfor Classic and 6.67 TS for COMPACT datatraffic. As can be seen, performance in Classicmode with one carrier per sector does notdepend on traffic load. This is because thecarrier transmits constantly; that is, channelutilization on the first carrier is always100%. As expected, average throughput inCOMPACT mode for a particular carrier de-74 Ericsson Review No. 2,2000
Figure 7Carrier throughput versus channel utilizationfor the first carrier using Classic andCOMPACT.creases with increased traffic load. Figure 8shows the maximum spectral efficiency andaverage throughput on the first carrier forthe different modes. Maximum spectral efficiencyis obtained when channel utilizationis 100%, which means that all capacityfor packet traffic is used. The data capacityfor COMPACT is 6.67 TS; for Classic, 7TS.If a second carrier is added, it can carrytraffic on all 8 TS for both modes, typicallyin a 1/3 frequency-reuse pattern. As seen inFigure 9, throughput for an additional carrierdepends on system load, for COMPACTas well as Classic.the radio-link simulations described abovewith 7 TS used for data traffic both forCOMPACT and Classic. As seen from Figure10, 10% percentile of packet throughputis plotted against the average numberof users per sector. The QoS limit is 10% ofthe available peak bit rate. COMPACT canhandle about 30 users per sector, whereasClassic can handle 60 users per sector.It is also interesting to study the distributionof user throughput, and not just the10% percentile of packet throughput. Figures11 and 12 show the cumulative distri-Dynamic packet-data systemsimulationsIt is easier to evaluate the system performance(simulation) of a packet-data networkif the traffic in the system is generateddynamically. The results discussed beloware based on dynamic simulations of packet-datatraffic where a large number of terminalsare studied over a period of time. 6 Apacket traffic model for Web-browsing trafficis used. 12 Table 3 summarizes the parametersused in the dynamic simulations.Figure 10 shows the number of users thatcan be served while guaranteeing thequality-of-service (QoS) limit of 90% of thepackets. The results are obtained with dynamicpacket-data system simulations andAverage throughput per carrier (kbit/s)Spectral efficiency (kbit/s/MHz/sector)Figure 8Throughput and spectral efficiency for thefirst carrier in Classic and COMPACT.Ericsson Review No. 2, 2000 75
Page 1: Ericsson 2/2000REVIEWTHE TELECOMMUN
Page 4 and 5: ContributorsIn this issueLuis Barri
Page 6 and 7: Ericsson Review is also published o
Page 8 and 9: Evolving from cdmaOne to third-gene
Page 10 and 11: Figure 2Operators Harmonization Agr
Page 12 and 13: more features, and greater reliabil
Page 14 and 15: Figure 7Ericsson's third-generation
Page 16 and 17: Figure 11Ericsson's timeline for ev
Page 18 and 19: Third-generation TDMAChristofer Lin
Page 20 and 21: TABLE 1 MODULATION AND CODING SCHEM
Page 22 and 23: Figure 3An example of a cell patter
Page 26 and 27: TABLE 3. DYNAMIC PACKET DATA SIMULA
Page 28 and 29: erage can be achieved in existing c
Page 30 and 31: Business solutions for mobile e-com
Page 32 and 33: Figure 2Comparison of traditional a
Page 34 and 35: BOX B, THE E-COMMERCE TIMELINE1999E
Page 36 and 37: Figure 6Mobile e-Pay end-user servi
Page 38 and 39: Figure 8Access features with push-a
Page 40 and 41: AuthenticationTo verify that end-us
Page 42 and 43: BOX C, MARKET HARMONIZATIONOn Tuesd
Page 44 and 45: Figure 2The footprint of the RBS 22
Page 46 and 47: Communications security in an all-I
Page 48 and 49: BOX B, SYMMETRIC KEY SYSTEMSGood sy
Page 50 and 51: Figure 4Construction of an ESP-prot
Page 52 and 53: Figure 7An X.500 database structure
Page 54 and 55: Figure 9GPRS VPN scenarios.Figure 1
Page 56 and 57: TRADEMARKSRC4 and RC4 are registere
Page 58 and 59: HIPERLAN type 2 for broadband wirel
Page 60 and 61: Figure 3Typical usage of communicat
Page 62 and 63: Figure 6Mapping of higher layer pac
Page 64 and 65: TABLE 1PHYSICAL LAYER MODES OF HIPE
Page 66 and 67: Queen City WaterfrontEMERGING PROJE
Page 68 and 69: TABLE 2. IMPORTANT PARAMETERS FOR N
Page 70: Previous issuesNo. 1,2000IPv6—The

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