which means that the MS generates only a very small noise rise compared with the noise floor of about À103.1 dBm (assuming a noise figure of 5 dB). The MCL problem can naturally also be encountered when an MS of a second operator is coming too close to the first operator’s BS. The difference, however, is that the MS is not power-controlled by the BS it is approaching. If the two operators have co-sited their BSs this is not critical, since then the second operator’s BS will command the MS to lower its power. In an ideal case there would not be any problems, since the operators are using different frequency carriers and there would be no interference between them. In reality, however, there are only finite values for ACS and ACLR (see Section 3.2.4). Assuming values of 33 dB and 45 dB, respectively, the coupling, C, between the carriers becomes: C ¼À10 Álog 10 ð10 À33=10 þ 10 À45=10 ÞdB ¼ 32:7dB ð3:73Þ This means that if the own MS and the other operator’s MS are transmitting with the same power, the interference received from the latter is about 32.7 dB less than that generated by the MS of the own system. The worst case scenario in the MCL problem, however, happens when some MS of the second operator is transmitting with its maximum power at the MCL distance from the BS of the other operator. This happens, for example, when the sites are not co-located. In an extreme situation one site is at the border of a cell of the other ope rator’s network. If then an MS is moving towards that border and in doing so it is approaching the first operator’s BS, it is transmitting with full power in the near vicinity of the first operator’s BS, as can be seen in Figure 3.26. With a maximum MS power of 21 dBm, 53 dB for MCL to the micro-BS and coupling between the carriers of C ¼ 32.7 dB, the received level at the micro-BS can be estimated as: 21 dBm À53 dB À 32:7dB¼À64:7 dBm ð3:74Þ WCDMA Radio Network Planning 165 Operator 2 Micro cell high TX power Operator 1 Macro cell Signal ACI Operator 1 MS dead zone Operator 2 Micro cell Signal ACI Operator 1 MS, max. TX power Operator 2 micro-cell Operator 1 macro-cell Operator 2 micro-cell high TX power Figure 3.26 Worst case scenarios in intra-system ACI. Right part: uplink; left part: downlink with dead zone. If the background noise level is À103.1 dBm, the micro-BS would suffer a 38.4 dB noise rise from one macro-user, which is located in the radio sense at the MCL distance from the micro-BS – i.e., such a macro-user would completely block the micro-BS. Next we calculate the situation on the downlink: consider that the micro-BS is transmitting with even minimum power of 0.5 W (27 dBm); then the received interfer- ence at the MS in the adjacent channel is: 27 dBm À53 dB (MCL) À 32:7 dB (ACS) ¼À58:7 dBm ð3:75Þ Assuming a speech service (processing gain of G p ¼ 25 dB) with an E b =N 0 requirement at the MS of 5 dB and an allowed noise rise in the macro-cell of 6 dB, the maximum allowed propagation loss, Lp, to keep the uplink connection working is: Lp ¼ 21 dBm À5dBþ25 dB ÀðÀ103 dBm þ6dBÞ¼138 dB ð3:76Þ Assuming a downlink transmit E b =N 0 requirement of 8 dB, the transmit power, P tx , would need to be: P tx ¼À58:7 dBm þ 8dBÀ 25 dB þ 138 dB ¼ 62: 3 dBm ð3:77Þ This simple example shows that clearly in these cases the downlink is the weaker link – i.e., before coming too close to a micro-BS, the connection of a macro-MS will be dropped due to insufficient downlink power and it cannot block the micro-BS. 3.6.3 Dead Zones Dead zones are another problem that can occur due to MCL problems. A dead zone is an area in which either the BS in the downlink or the MS in the uplink does not have enough transmit power to maintain the QoS requirements of the other end. When entering such an area an existing connection is lost and it is not possible to establish a connection from that area. One possible scenario where a dead zone can arise is again in a multi-operator environment, if an MS from one operator is approaching at the cell edge a (micro-) BS from another operator that is transmitting with full power. Then the own BS does not have enough transmit power to overcome the interference generated from the second BS. This will be the case in a certain area around the second BS. Alternatively, or simultaneously, it might happen that the MS can no longer reach its own BS. Due to a smaller MCL, the problem is more severe around a micro-BS than around a macro-BS. Additionally, the link loss from the cell edge to the BS is bigger in macro-environments. Therefore, the most typical case for a dead zone will be for an MS of a macro-operator around the BS of a micro-operator. However, it depends on the scenario whether this MS will first lose its conn ection or whether it will first block the uplink of the micro-BS. An example of dead zones can be seen in Figure 3.27. 3.6.4 ACI Simulation Cases 3.6.4.1 Two Macro-cellular WCDMA Networks in an Urban Environment In earlier work published in the field [41] and [42] the simulation scenario has been rather unrealistic. It is rather unlikely that in an (dense) urban area one operator would 166 Radio Network Planning and Optimisation for UMTS choose to employ a micro-cellular network modelled with a Manhattan grid, while another operator would see it feasible to provide services with a macro-cellular network. This section describes the network simulation results of a study on the mutual influence of two macro-cellular WCDMA radio networks when operating in the same area. Both operators’ networks were of macro-cellular type, locat ed in an urban environment in the city centre of Helsinki (Finland). Both operators were assumed to have the same traffic and QoS requirements. The first phase of the analysis considered the two operators’ networks to be independent from each other – i.e., without experiencing the influence of external interference from the other operator’s network. In the second phase, the influence of the interference leaking from one operator’s network to the other’s was taken into account by filtering the transmit powers from one operator to the other. In the whole study the two operators were considered to operate in immediately adjacent channels separated by 5 MHz. No other neighbouring channel interference was taken into account. The values of the minimum transmit power for the mobiles and the filter settings were chosen on a best guess basis, as their standardisation was not finished at the time of the study. Urban Simulation Case In the urban simulation case a 9 km 2 area in the city centre of Helsinki was analysed. The dimensioning proposed 13 sites (38 sectors) for the coverage and the required capacity. Because in reality some 20% of the total area is water, the actual network planning was done with 32 sectors, of which 31 used 65  /17.5 dBi sector antennas and one 11 dBi omni-antenna. The selected antenna installation height was from 16 m to WCDMA Radio Network Planning 167 Figure 3.27 Example of downlink link power needed for a macro-operator’s network. Also visible are some dead zones, where the maximum link power is not sufficient for good enough quality of service. 20 m and the propagation loss was calculated with the Okumura–Hata model, with an average area correction factor of À6.3 dB. For users inside the buildings an additional propagation loss of 12 dB was added. Two independent network layouts were created. The network scenarios can be seen in Figure 3.28. The system features used in the simulations are from [37], except the chip rate which was modified to 3.84 Mcps. The multi-path channel profile was the ITU Vehicular A channel [29]. For the soft handover window a value of À5 dB was used – i.e., all sectors whose received P-CPICH are received within À5 dB of the strongest P-CPICH are in the active set. The maximum allowed uplink loading was set to 75%. Other relevant parameters applied in the simulations are listed in Table 3.31. The traffic requirements were as in Table 3.9. Simulation Results In this section results from the urban simulation case are collected. The numbers presented are averages over three different MS distributions following the traffic requirements of Table 3.9. Table 3.32 lists the uplink coverage probabilities. The requirements are well-met, except that the 384 kbps coverage is slightly too small. If a second operator is present, coverage does not drop significantly. Table 3.33 gives an overview on the MS transmit powers in terms of maximum and minimum powers used, as well as the 50, 75 and 95 percentiles. In this case, too, no significant increase is noticed when introducing the influence of a second operator. Mobiles using their minimum allowed transmit powers indicate that there could be some problems in the network arising from excessive MCL, though no consequences, such as downlink dead zones, have been observed. Table 3.34 shows the transmit powers in the downlink. Statistics from both the single-link powers and the total transmit powers are collected. If a second operator is 168 Radio Network Planning and Optimisation for UMTS Figure 3.28 Used network scenarios in the urban case. introduced, transmit powers increase slightly, though no dramatic effects could be noticed. In Table 3.35 the average number of users per cell, the uplink load, the average number and type of links per cell and the soft handover overhead are given. Again, these resul ts indicate that with the chosen filter values no significant influence from the neighbouring operator is experienced. WCDMA Radio Network Planning 169 Table 3.32 Uplink coverage in urban case. Uplink coverage Speech 64 kbps 144 kbps 384 kbps One operator 99.23% 96.27% 93.63% 89.13% Two operators 99.19% 96.18% 93.52% 88.93% Table 3.33 Mobile station transmit powers in the urban case. MS transmit powers [dBm] Max. Q95 Q75 Q50 Min. One operator 17.82 9.39 À1.06 À7.86 À44.0 Two operators 18.01 9.50 À0.90 À7.73 À44.0 Reproduced by permission of IEEE. Table 3.31 Parameters used in the simulations. Chip rate 3.84 Mcps BS maximum transmit power 43 dBm MS minimum/maximum transmit power À44 dBm a /21 dBm Shadow fading correlation between sites/sectors 50%/80% Standard deviation for shadow fading 7 dB Channel profile ITU Vehicular A [29] MS speed 3 km/h for data, 50 km/h for speech MS/BS noise figures 8 dB/5 dB P-CPICH power 30 dBm Combined power for other common channels 30 dBm Orthogonality 50% MS antennas Omni, 0 dBi Cable losses 3 dB Filter settings – Equations (3.58) and (3.60) aciFilterUL (BS selectivity, ACS) 45 dB acpFilterUL (MS leakage, ACLR) 33 dB aciFilterDL (MS selectivity, ACS) 33 dB acpFilterDL (BS leakage, ACLR) 45 dB a In this study, the minimum transmit power of the mobile station was À44 dBm. In 3GPP standards this value was adjusted later to À50 dBm. Reproduced by permission of IEEE. Conclusions In this study the influence of two operators on each other in a macro-cellular environment was investigated for an urban area. Owing to the relatively tight filter settings describing the mutual influence, network performances did not suffer significant degradation. Almost the same performance with and without the second operator was achieved. The biggest degradation was observed for the outage probabilities, but the changes were not too dramatic as the outage was only slightly increased. In this urban study none of the so-called dead zones could be observed. One explanation for this could be that the link losses were calculated using an Okumura– Hata model without LOS check, so the minimum link losses were bigger than the minimum coupling loss required to avoid the problem. The result could, however, be different if an LOS check were used, especially in a scenario where there are BSs of two operators aligned along streets or even highways. The same reason lies behind the observation that there was no significant difference in performance wheth er cells of different operators were almost co-located or whether they were positioned at each other’s cell edge. Another case in which networks are located in a suburban area can be found in [43]. Those results indicate the same behaviour in terms of ACI. 3.6.4.2 Macro- and Micro-cellular WCDMA Networks in an Urban Environment In this ACI exercise the two networks comprised one macro- and one micro-cellular layout, operated on adjacent carriers servicing the same urban area (downtown 170 Radio Network Planning and Optimisation for UMTS Table 3.35 Other results from the urban case. Users Load Links Soft handover 12.2 kbps 64kbps 144 kbps 384 kbps overhead One operator 21.27 0.54 26.83 2.16 1.38 0.71 0.47 Two operators 21.44 0.55 27.18 2.18 1.43 0.66 0.47 Reproduced by permission of IEEE. Table 3.34 Base station transmit powers in the urban case. Max. Q95 Q75 Q50 Min. Link power statistics [dBm] One operator 36.16 29.55 22.60 21.43 16.36 Two operators 35.85 29.76 22.90 21.63 16.52 Total power statistics [dBm] One operator 42.05 41.36 39.93 38.55 34.35 Two operators 42.30 41.75 40.04 38.74 34.67 Reproduced by permission of IEEE. Helsinki) as in the previous section with sufficient capacity an d coverage. The dimensioning in this case suggested that the macro-operator has 32 cells and the micro-operator 46 cells in an area of about 4 km 2 . In the simulations the basic idea was that each operator optimises its network first so that the outage was below 2%, without considering the other operator. Therefore, the cell plans are totally independent. In the real case the parameters could be optimised in a more efficient way. The propagation environments were calculated using a ray-tracing program for the micro-cell scenario and the Okumura–Hata model for the macro-cell scenario. In the study the micro-/macro-scenarios were first analysed independently. Then the scenarios were combined and the interactio n of these two operators in the form of interference was deduced. Both network-based indicators and cell-based indicators were of interest. The general simulation parameters are listed in Table 3.36. These serve as default values, if not stated otherwise, in the simulation cases. 3.6.4.3 Simulations in Helsinki with 32 Macro-cells and 46 Micro-cells Figure 3.29 shows the cell plans used in the simulation together with the studied area. For each simulated case three snapshots with random positions of MSs were used. On average, 20, 25, 30 and 35 users per cell were input for the macro-operator and 55, 65, 75 and 85 users per cell on average for the micro-operator. WCDMA Radio Network Planning 171 Table 3.36 Some general simulation parameters. Macro Micro Maximum BS power 43 dBm 36 dBm Maximum downlink transmit power per link 40 dBm 33 dBm P-CPICH power 30 dBm 23 dBm Other common channel powers 30 dBm 23 dBm Soft handover window 3 dB 3 dB BS antenna height 25.0 m 10.0 m MCL 70 dB 53 dB BS selectivity/leakage 45 dB 45 dB MS selectivity/leakage 33 dB 33 dB Minimum MS transmit power À44 dBm À44 dBm Shadowing standard deviation/correlation between BSs 7 dB/0.5 7 dB/0.5 384200 384600 385000 385400 385800 386200 386600 387000 387400 387800 6674000 6674400 6674800 6675200 6675600 6676000 BS 1 BS 2 BS 3 BS 4 BS 5 BS 6 BS 7 BS 8 BS 9 BS 10 BS 11 BS 12 BS 13 BS 14 BS 15 BS 16 BS 17 BS 18 BS 19 BS 20 BS 21 BS 22 BS 23 BS 24 BS 25 BS 26 BS 27 BS 28 BS 29 BS 30 BS 31 BS 32 384200 384600 385000 385400 385800 386200 386600 387000 387400 387800 6674000 6674400 6674800 6675200 6675600 6676000 BS 1 BS 2 BS 3 BS 4 BS 5 BS 6 BS 7 BS 8 BS 9 BS 10 BS 11 BS 12 BS 13 BS 14 BS 15 BS 16 BS 17 BS 18 BS 19 BS 20 BS 21 BS 22 BS 23 BS 24 BS 25 BS 26 BS 27 BS 28 BS 29 BS 30 BS 31 BS 32 BS 33 BS 34 BS 35 BS 36 BS 37 BS 38 BS 39 BS 40 BS 41 BS 42 BS 43 BS 44 BS 45 B S Figure 3.29 The macro- and micro-operators’ cell plans. Simulation Results This section and the figures that follow give the main simulation results for macro- and micro-operators with and without the other operator present. Service probability (number of users served after iterations divided by initial number of users), uplink noise rise and BS total transmit power are shown. In addition, performance has been studied with two settings of the maximum traffic channel power for a single link in the downlink: 5.5 dB below CPICH (left diagrams) and 0 dB below CPICH (right diagrams). The latter corresponds to an aggressive parameter setting to avoid dead zones. All the curves show averages from all three snapshots and the powers averaged over the cells. The x-axis is always ‘Number of users’ or ‘Number of served users’: this means on average per cell, as the traffic was generated uniformly onto the area. For the macro-cells only ‘inner cells’ on the area were included in the cell-based analysis to avoid bias from border effects. From the simulation results one can see that there is always a significant loss of downlink performance for the macro-operator. If the loading in the macro-operator’s network is low, an aggressive parameterisation (allowing high transmit power for the traffic channels) may help slightly and make the micro-operator’s life slightly more difficult, but for high loading it does not help. Also one can see that if the macro- operator uses aggressive parameterisation the micro-operator can suffer in the uplink because of a slightly bigger noise rise. Simulation Results for the Macro-operator (Figures 3.30–3.32) 85 90 95 100 20 30 40 50 60 Number of users per cell (input) Service probability (%) Macro alone Macro with micro 85 90 95 100 20 30 40 50 60 Number of users per cell (input) Service probability (%) Macro alone Macro with micro Maximum link power 5.5 dB below CPICH Maximum link power equals CPICH Figure 3.30 Service probability of the macro-operator when alone and with the micro-operator. 0 0.5 1 1.5 2 2.5 3 3.5 20 30 40 50 60 Number of served users per cell UL noise rise (dB) Macro alone Macro with micro 0 0.5 1 1.5 2 2.5 3 3.5 20 30 40 50 60 Number of served users per cell UL noise rise (dB) Macro alone Macro with micro Maximum link power 5.5 dB below CPICH Maximum link power equals CPICH Figure 3.31 Uplink noise rise of the macro-operator when alone and with the micro-operator. 172 Radio Network Planning and Optimisation for UMTS 30 35 40 20 30 40 50 60 Number of served users per cell Total BS Tx power (dBm) Macro alone Mac ro with m ic ro 30 35 40 20 30 40 50 60 Number of serve d users per cell Total BS Tx power (dBm) Macro alone Macro with micro Maximum link power 5.5 dB below CPICH Maximum link power equals CPICH Figure 3.32 Total base station transmit power of the macro-operator when alone and with the micro-operator. No pure capacity effects can be seen from these simulations – i.e., moving the pole capacity – but according to the results one could think of adding the effect of the adjacent carrier, if cell planning between the macro- and micro-layers is un- coordinated, as an offset to the noise level in dimensioning. In the optim isation process the other operator on the adjacent carrier should be taken into account to avoid local dead zones. Simulation Results for the Micro-operator (Figures 3.33–3.35) 85 90 95 100 50 60 70 80 90 Number of users per cell (input) Service probability (%) Micro alone Micro with macro 85 90 95 100 50 60 70 80 90 Number of users per cell (input) Service probability (%) Micro alone Micro with macro Maximum link power 5.5 dB below CPICH Maximum link power equals CPICH Figure 3.33 Service probability of the micro-operator when alone and with the macro-operator. 0 1 2 3 4 5 50 60 70 80 90 Number of served users per cell UL noise rise (dB) Micro alone Micro with macro 0 1 2 3 4 5 50 60 70 80 90 Number of served users per cell UL noise rise (dB) Micro alone Micro with macro Maximum link power 5.5 dB below CPICH Maximum link power equals CPICH Figure 3.34 Uplink noise rise of the micro-operator when alone and with the macro-operator. WCDMA Radio Network Planning 173 25 30 35 50 60 70 80 90 Number of served users per cell Total BS Tx power (dBm) Micro alone Micro with macro 25 30 35 50 60 70 80 90 Number of served users per cell Total BS Tx power (dBm) Micro alone Micro with macro Maximum link power 5.5 dB below CPICH Maximum link power equals CPICH Figure 3.35 Total base station transmit power of the micro-operator when alone and with the macro-operator. Conclusions The macro-operator is more affected by the micro-operator than vice versa. The macro- operator can lose downlink coverage near the micro’s BSs. The micro-operator’s uplink noise rise can be slightly higher because of the macro’s MSs if the macro-operator uses aggressive downlink power allocation (giving high power for a single MS). No clear capacity effects were found but only coverage effects. Downlink dead zones can occur in such places where the macro-cell boundary is close to the micro-operator’s BS (the micro–micro case is probably easier, since in most cases the cell boundaries are inside buildings for both operators). The problem is made worse by a larger average path loss difference. 3.6.5 Guidelines for Radio Network Planning to Avoid ACI The simulations in Section 3.6.4 prove that with proper radio network planning the severest problems with ACI within WCDMA can be avoided to such a level that the WCDMA network performance does not suffer significant degradation. This section gives a summary of the most popular radio network planning means to alleviate ACI problems. . BS and antenna locations: e in macro-cellular-only environments, the natural distance between the MS an d BS is normally large enough to provide sufficient decoupling. In mixed environments, however, when micro-cells and pico-cells are present, the minimum coupling loss is usually not enough to avoid interference problems. In such cases it is desirable that operators try to co-locate BSs, since then there is no possibility that an MS that is close to the cell edge of one operator comes close to the BS of the other operator; e if co-location is not achievable then one means to increase the MCL is to deploy the antennas in a position as high as possible above the MS; e other possibilities to reduce interference between operators are proper selection of the antenna direction and the correct tilting of the antennas. . Base station configuration: e after selection of the correct sectorisation to meet the coverage and capacity requirements, for each configuration there exists an optimum antenna beamwidth. 174 Radio Network Planning and Optimisation for UMTS [...]... power 0.93 1 .41 0.55 0.58 0.16 0. 24 35.2 36.6 0.16/2. 54 0.19 0.19 0 .44 0 .48 /1.36 0.20 0.23/1.02 0.27/3.18 0.33 1.03 1.28 1.27 1.13 0.11/0.0 0.06 0.12 0.20 0.27/0 .49 0.12 0.12/0 .43 0.13/0.26 0.23 0 .44 0.55 0.76 0 .48 0.76/0. 04 0.59 0.78 0 .49 0.78/0.60 0 .45 0.73/0.15 0 .49 /0.17 0.19 0.23 0.33 0.12 0.21 34. 3/27.6 32.2 34. 0 31.6 35.0/30.5 32.3 35.2/28 .4 32.1/28.3 35.8 35.6 36 .4 34. 6 35.7 Figure 3 .43 Served... configuration for the network regions are determined, and the work schedule and instructions for civil engineering and equipment installation are generated for site deployment Transmission requirements WCDMA Radio Network Planning 177 are estimated and transmission planning is performed A part of the radio network and transmission planning is the preparation of parameter files and templates for the ATM layer and. .. 0.17 0.19 0. 54 0 .41 0.20 0.23 0.27 0 .43 1.10 0.83 0.82 1.09 0.13 0.06 0.11 0.20 0.20 0.15 0. 14 0.13 0 .42 0.39 0.28 0. 24 0.39 0.75 0.60 0.76 0 .47 0.79 0 .47 0.73 0 .49 0.19 0.28 0 .41 0.12 0. 24 34. 4 32.2 34. 1 31.7 35.1 32.6 35.3 32.1 35.3 35.5 36.9 34. 3 35.8 (b) Micro f1, macro f1 þ f2 Micro 8 9 12 13 19 20 21 Mean (all cells) Macro 12 13 14 15 Mean (all cells) 100.3 83.0 37.3 23.3 59.0 34. 7 78.3 43 .5 73.0/25.0... 34. 7 78.3 43 .5 73.0/25.0 75.0/23.0 46 .7/10.7 58.0/10.3 56 .4/ 19.1 0.20 0.19 0.63 0.97 0.70 0 .43 0.28 0 .46 1.05/0 .41 1.25/1.03 1.21/2.22 0.98/1.03 1.03/1.31 0. 14 0.07 0.62 0.26 0.51 0.23 0.21 0. 24 0.57/0.31 0 .44 /0.33 0.78/1.30 0.60/0.95 0.53/0.71 0.65 0.53 0 .48 0.29 0. 64 0.32 0.59 0.38 0.59/0.19 0.59/0.21 0.51/0. 24 0.51/0.13 0 .47 /0.18 34. 1 32.2 32.9 30.1 34. 8 30.6 34. 3 31 .4 38.0/33.2 38.1/32.8 37.6/32.5... per micro-sector Figure 3 .41 Service probabilities for the different base station and network configurations given in Table 3.39 (d) Number of initial users per (micro-) sector Figure 3 .42 Reasons for not serving mobiles (a), (b), (c) and (d) refer to the base station and network configurations given in Table 3.39 Radio Network Planning and Optimisation for UMTS 186 Table 3 .40 Served users, other-to-own-cell... (c) and (d) refer to the base station configurations given in Table 3.39 188 Radio Network Planning and Optimisation for UMTS Figure 3 .44 Other-to-own-cell-interference, i (a), (b), (c) and (d) refer to the base station configurations given in Table 3.39 Figure 3 .45 Average soft handover overheads (a), (b), (c) and (d) refer to the base station configurations given in Table 3.39 WCDMA Radio Network Planning. .. in the network configuration For 3G greenfield operators, rollout includes radio network planning, site acquisition, packet core network planning, construction work, commissioning and integration of the network elements In the radio network planning phase, dimensioning and site acquisition information is combined with the traffic and service quality requirements, see Section 3.1 The site density and configuration... fast with appropriate performance optimisation Immediate feedback from network performance is also needed for providing information for network development tasks and plans More about measurement-based configuration tuning in a Network Management System (NMS) can be found in Sections 7.3.3 and 9.3 For GSM operators the radio network planning phase is slightly different Information (location, height, possible... transmission 190 Radio Network Planning and Optimisation for UMTS Figure 3 .46 Average uplink loading (a), (b), (c) and (d) refer to the base station configurations given in Table 3.39 Figure 3 .47 Average base station transmission powers (a), (b), (c) and (d) refer to the base station configurations given in Table 3.39 WCDMA Radio Network Planning 191 power is clearly the most limiting factor reducing the network. .. WCDMA network can be divided in certain micro- and macro-cell scenarios, which could occur during WCDMA network deployment phases The most important thing to avoid is excessive increase of interference levels in both the uplink and downlink, and it is essential to keep soft 1 94 Radio Network Planning and Optimisation for UMTS handover areas restricted so that carrier reuse is able to bring some performance . case. Users Load Links Soft handover 12.2 kbps 64kbps 144 kbps 3 84 kbps overhead One operator 21.27 0. 54 26.83 2.16 1.38 0.71 0 .47 Two operators 21 .44 0.55 27.18 2.18 1 .43 0.66 0 .47 Reproduced by permission. schedule and instructions for civil engineering and equipment installation are generated for site deployment. Transmission requirements 176 Radio Network Planning and Optimisation for UMTS are. out includes radio network planning, site acquisition, packet core network planning, construction work, commissioning and integration of the network elements. In the radio network planning phase,