1、 1” STD-CEPT ERC REPORT 67-FREN 1999 232b414 0016049 ZIT ERC REPORT 67 European Radiocommunications Committee (ERC) within the European Conference of Postal and Telecommunications Administrations (CEPT) Study of the Frequency sharing between HIPERLANs and MSS feeder links in the 5 GHz band Marbella,
2、 February 1999 “I Copyright 1999 the European Conference of Postal and TeI,c:iii.iil,nlions Adniiriistrations (CIEPT) STD=CEPT ERC REPORT b7-FREN 1999 m 2326434 001b051 978 m ERC REPORT 67 STUDY OF THE FREQUENCY SHARING BETWEEN HIPERLANS AND MSS FEEDER LINKS IN THE 5 GHZ BAND 1 INTRODUCTION . 1 2 RE
3、GULATORY STATUS OF HIPERLANS 1 3 METHODOLOGY . 2 MAXIMUM TOLERABLE INTERFERENCE FOR MSS FEEDER LINKS FROM HIpERLANS 2 Noise temperature increase at satellite receiver 2 MAXIMUM TOLERABLE NUMBER OF ERLANs . 3 DISCUSSION ON THE VALDKY OF EACH METHODOUH-iY 4 4 TECHNICAL PARAMETERS 5 MAXIMUM TOLERABLE I
4、NTERFERENCE FOR THE MSS FEEDER LINK FROM HIPERLANS . 5 4.1.1 4.1.2 Remaining Parameters . 5 4.2 MAXIMUM TOLERABLE NUMBER OF HJPERLANs . 6 4.2.1 4.2.1.1 4.2.1.2 Additional loss due to obstacles around the buildings . 8 4.2.1.3 Multipaih effect 8 4.2.2 Activity rutio per device Ra: 9 4.2.3 Average HIP
5、ERLAN ElRP Ph: 9 4.2.4 Mean or peak power (meaning of the figures used in the calculation): . 10 4.2.5 4.2.6 Remaining Parameters: . 10 5 CALCULATION RESULTS . 10 3.1 3.2 3.1.1 3.3 4.1 Criterion for the tolerable noise increase Cr . 5 Average loss in excess offree space loss for HIPERLAN indoor use
6、Lsi: . 6 Shielding loss due to indoor to outdoor (one building) . 6 Proponion assigned to HIPERLAN outdoor usage Ro: 10 6 SUMMARY OF RESULTS . 11 7 CONCLUSIONS . 11 ANNEX 1 : EXCAMPLES OF CALCULATION RESULTS . 13 ANNEX 2 :ADDITIONAL LOSS TO FREESPACE PATH LOSS IN THE CASE OF GSO FSS . 17 ANNEX 3 : C
7、ALCULATION OF y FACTOR 19 STD-CEPT ERC REPORT b7-FREN 1999 2326434 0016052 804 ERC REPORT 67 Page 1 STUDY OF THE FREQUENCY SHARING BETWEEN HIPERLANS AND MSS FEEDER LINKS IN THE 5 GHZ BAND 1 INTRODUCTION WG SE has studied the issue of compatibility between HPERLANs and NGSO MSS feeder links within th
8、e 5 150-5250 band MHZ for almost two years. This report has been issued after considerable debate and active participation from ETSI and MSS operators. Two particular MSS networks are taken into account in this report, Globalstar and ICO, which are those operating in this band and have started to co
9、mply wi.th the CEFT MRC milestones. The HIPERLAN characteristics that are taken into account are those specified by ETSI (in as HIPERLAN Type 1: ETS 300 652). Characteristics of HIPERLAN type 2 (under the process of standardisation within ETSI) have not been precisely taken into account due to the l
10、ack of reliable and stable information, but the compatibility issue is expected to be very similar. MSS and HIPERLAN communities have been in disagreement on several parameters and this report is based on values which are assumed to reflect conservative worst case assumptions and which have been agr
11、eed in WG SE and some also in the special ERM Experts meeting held in February 1998, endorsed by ERM. Administrations also found it difficult to agree on the methodology and criteria, taking into account the relative regulatory status of HIPERLAN and MSS, for the evaluation of the protection require
12、ments for MSS networks, reflecting diverging views on what should be considered as “harmful interference“. This report describes the methodologies and the parameters, which are taken into account in the studies. It will also explain where the areas of disagreement lie. It also provides recommendatio
13、ns, which should enable sharing as practicable. It is also noted that the content of this ERC report has been the basis for European input to ITU-R and is therefore expected to be reflected, with modifications, in some ITU-R output documents (Recommendation or Report). 2 REGULATORY STATUS OF HIPERLA
14、Ns One of the difficulties continuously faced by WG SE on the compatibility between MSS feeder links and HIPERLANs was the regulatory status of HIFERLANs in regards to MSS feeder links. This potentially impacts the choice of the methodology and the criteria used for the compatibility calculation. MS
15、S Feeder links are allocated with a primary world-wide status in 5 150-5250 MHz. In the Radio Regulations. S5.447 allocates Mobile Service in the band 5150-5250 MHz on a primary basis in several CEPT countries, but subject to agreement obtained under No. S9.21 (Article 14). In absence of such agreem
16、ent, as it is the case, HIPERLANs can only be operated under article S4.4, i.e. not in accordance with the table of international allocations and, as such, HIPERLANs shall not cause harmful interference to MSS Feeder links nor claim protection. On the other hand, WG FM, in answer to a liaison statem
17、ent from WG SE, clearly answered that HIPERLAN and MSS Feeder link should be regarded as Co-primary in Europe, in countries in S5.447. However, given the global nature of MSS feeder links, such a position was not easy to apply and WG SE tried to concentrate on the RR situation. STD-CEPT ERC REPORT 6
18、7-FREN 1999 m 2326414 00Lb053 740 m ERC REPORT 67 Page 2 3 METHODOLOGY It is very difficult to estimate the possible number of HIPERLANs that could be deployed in the long term over a whole continent. For this reason, it has been decided to adopt a methodology that starts by estimating the maximum t
19、olerable interference from all the HIPEIUANs within the satellite footprint. Once this figure is decided, taking into account the characteristics of HIPERLANs and their conditions of deployment, one can evaluate the maximum tolerable number of HIPEIUANs within the satellite footprint. 3.1 In order t
20、o assess the maximum tolerable interference from HPEIUANs to the MSS feeder link, two methodologies have been proposed so far, both based inter alia on the contents of Appendix S8 of the RR. Maximum tolerable interference for MSS feeder links from HIPERLANs 3.1.1 The first one is based on the appare
21、nt increase in noise temperature at the satellite receiver, the increase in system noise temperature at the satellite receiver ATsat is shown as: Noise temperature increase at satellite receiver ATsat = Cr x Tsat (1) where, Tsat: the receiver system noise temperature of the space station, referred t
22、o the input of the satellite receiver (NOTE, in Appendix S8 it is referred to the output of the receiving antenna: in the tables in the Annex 1, this parameter has been used in the case of IC0 network - see note 2 in Annex 1) Cr: criterion for the tolerable noise increase. The tolerable aggregate HI
23、PERLAN interference in one MSS channel, I, is given by: I = Cr x k x Tsat x Bs x Lf x Lfl/ Gs where, k: Bolzmann constant Bs: bandwidth of a MSS channel, LE free space loss of the uplink, Gs: satellite receiving antenna gain, Lfl: feeder loss of the satellite receiver. Therefore, tolerable aggregate
24、 HIFERLAN interference per HPERLAN channel Ih can be represented by: Ih = I x Bh/ Bs = Cr x k x Bh x Tsat x Lf x Lfl/ (Gs) (3) where, Bh: HIPERLAN channel bandwidth. 3.1.2 Noise temperature increase on overall MSS link The second methodology is based on the increment in the noise temperature on the
25、overall MSS link. The overall link system noise temperature Tlink is represented as: Tiink =y x Tsat + Tearth where, Tearth: system noise temperature at the mobile receiver; y: satellite system gain, calculated as follows: STD-CEPT ERC REPORT b7-FREN 1999 232b414 0016054 b87 ERC REPORT 67 Page 3 y =
26、 Pb / Pa with Pa is the power of the uplink at the satellite receiver input, and Pb is the power of the downlink at the mobile receiver input. The increase in the system noise temperature ATsat at the input of the LNA can be represented as: ATsat = Cr x (y x Tsat + Tearth)/y (6) The tolerable aggreg
27、ate KIPERLAN interference on the earth surface just under the satellite (I) is given by: I = Cr x k x Bs x Lf x Lfl x (y x Tsat + Tearth) / (y x Gs) (7) Therefore, the tolerable aggregate HIPERLAN interference per HIPERLAN channel (Ih) can be represented by: Ih = I x Bh / Bs = Cr x k x Bh x Lf x Lfl
28、 x (y x Tsat + Tearth) I (y x Gs) (8) 3.2 Given that the proportion Ro is assigned to KIPERLAN outdoor usage, the weighted loss in excess of free space loss for HiPERLANs Ls can be calculated by: Maximum tolerable number of HIPERLANs ins = RO + Rins (9) where, Ri: ratio assigned to HIPERLAN indoor u
29、sage (= 1- Ro), Lsi: average loss in excess of free space loss for HIPERLAN indoor use. Taking account of the characteristics of HPERLAN propagation conditions and MSS receivers, the maximum tolerable interference on earth per HIPERLAN channel It can be expressed as: where, Fd: polarisation discrimi
30、nation factor between MSS and HIPEIUANs (since HIPERLAN interference is not polarised). Therefore, the maximum tolerable number of instantaneous transmitting HIPERLANs per HPERLAN channel Nact can be calculated by: Nact = It / Ph (1 1) where, Ph: average HIPERLAN ER? Taking into account the activity
31、 ratio per device Ra, the maximum tolerable number of indoor and outdoor deployed HIPERLANs Nt per HIPERLAN channel within the satellite footprint is given by: Nt = Nact / Ra (12) STD-CEPT ERC REPORT b7-FREN 1799 = 232b414 00Lb055 513 W ERC REPORT 67 Page 4 3.3 The two calculation methods, as shown
32、in Eqs. (3) and (S), give some very different results, due to the fact that y is generally well below 1. Thus equation (8) leads to a maximum number of HIPERLAN terminals much higher than equation (3). Discussion on the validity of each methodology Appendix Si3 explains that : Eq (8) is valid for no
33、n regenerative satellites Eq (3) is valid for regenerative satellites The first generation of Globalstar and IC0 satellites are non regenerative satellites. However, both operators have indicated that future generations might use regenerative satellites, particularly to compensate for the expected r
34、eduction in MSS feeder link 5GHz spectrum in 2010 from 160 MHz to 100 MHz. The disagreement on the interpretation of whether ATsat or ATlink should be used is summarised by the two following statements : The ATsat proponents believe that ATsat is the correct method to be used for both first and seco
35、nd generation satellites to ensure the protection of MSS satellites in the long term. ATsat proponents point out that that the licence exempt nature of HIPERLANs would make it impossible to clear the band for second generation satellites, which may be more susceptible to interference than first gene
36、ration. They also emphasise that the ITU-R regulatory status of HIFElUANs means that the primary MSS is also protected for future systems. The ATlink proponents believe that is more appropriate for first generation, non-regenerative satellites and that ATsat is more appropriate for second generation
37、, regenerative satellites. ATlink proponents stress that despite the ITU-R regulatory status of HIPERLANs, MSS operators should take into account the existence of HIPERLANs and not make their second generation systems more susceptible to interference than the first generation. . 0 In order to have a
38、n idea of the impact of the choice between the AT,flSaI and the AT, and the increase due to multipath effect. One aim of this section is to show two models produced during the discussion on the indoor to outdoor loss, some considerations on the additional loss due to obstacles around a building and
39、some simplistic considerations on the multipath effect. Average loss in excess offree space loss for HIPERLAN indoor use hi: 4.2.1.1 Shielding loss due to indoor to outdoor (one building) Several papers have considered the properties of materials and the topology of a typical building. It is very ha
40、rd to say what a typical building is over an entire continent and this has been the main issue of a long discussion. A difficult compromise for the overall figure to be considered for the study relative to Globalstar and IC0 systems was reached in ERM expert group is as follows: 10dBforICO. 9 dB for
41、 Globalstar and STD-CEPT ERC REPORT 67-FREN 1999 m 232b414 003ib058 222 m ERC REPORT 67 Page 7 This compromise was based on the two following models. In both models, the loss depends on the elevation of the satellite and both already include the additional loss due to propagation inside the building
42、. The models are as follows: Model 1) Lsh = 8 dB Oc lOdeg. 1 O deg. 8 45 deg. Lsh = 10 dB Model 1 Lsh = 15 dB 45 deg. c 90 deg. -8 -9 -1 o -1 1 3 -1 -1 2 -1 3 -1 4 -1 5 Model 2) Indoorloutdoor additional loss at 5 GHz 10 20 30 40 50 60 70 BO 90 E levat ion Lsh = -8.4-(0.038*8)/2 Model 2 Indoorloutdo
43、or additional loss at 5 GHz -22 I O 10 20 30 40 50 60 70 BO 90 Elevation STD=CEPT ERC REPORT 67-FREN 1999 232b414 00Lb059 169 W Model 1, x=O Model 1, x=50, p=50, el=10 Model 1, x=50, p=70, el=10 Model 2, x=O Model 2, x=50, p=50, el=10 Model 2, x=50.11=50, el=20 ERC REPORT 67 Page 8 shielding) L = 9.
44、2 dB L = 10.6 dB (A = 1.4 dB) L = 11.4 dB (A = 2.2 dB) L = 9.0 dB L = 10.2 dB (A = 1.2 dB) L = 10.9 dB A = 1.9 dB) - 4.2.1.2 Additional loss due to obstacles around the buildings In order to take into account the additional shielding due to obstacles around the building, the same models can be modif
45、ied saying that, for example, p% (50%) of the paths for low elevation angles up to el deg. ( 10 deg.) are completely blocked or, equivalently, there is an additional x dB (50 dB) loss on those paths. What is important is the difference in dB from the figures derived from the models for each satellit
46、e network considered, so that we propose to observe the difference using the two models and an assumed increase of 50 dB in the attenuation on half of the paths for the two MSS satellite networks planned to operate in the band. For the Globalsiar network (altitude of 1414 km) we obtain: Model and pa
47、rameters Model 1, x=O Model 1, x=50, p=50, el=10 Model 1, x=50, p=70, el=10 Model 2, x=O Model 2, x50, p=50, el=10 Model 2, x=50, p=50, el=20 Model 2, x=50, p=70, el=10 I Model and parameters I Shielding (A from same model without additional I Shielding (A from same model without additional shieldin
48、g) L= 1odB L= 11 dB (A= 1 dB) L = 11.3 dB (A = 1.3 dB) L = 9.7 dB L = 10.4 dB (A = 0.7 dB) L=11dB(A=11.3dB) L = 10.8 dB (A = 1.1 dB) I Model 2, x=50, p=70, el=10 I L = 10.8 dB (A = 1.8 dB) I The table shows that the additional effect due to obstacles around the building is not enormous and can be es
49、timated as follows: 0 around 1.5dB. For the IC0 network (altitude of 10355 km), we obtain: The table shows that the average additional loss can be presented by: It was noted that there is a lot of uncertainty on the validity of these assumptions due to the wide range of diverging values, which have been found in the literature. The values selected here are considered as conservative worst case assumption. 4.2.1.3 Multipath eflect Few papers have been produced on this issue. One indicates that the potential increase in noise due to multipath that can be perceived at th
