1、 International Telecommunication Union ITU-T G.9902TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1(03/2013) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Access networks In premises networks Narrowband orthogonal frequency division multiplexing power line communi
2、cation transceivers for ITU-T G.hnem networks Amendment 1 Recommendation ITU-T G.9902 (2012) Amendment 1ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOG
3、UE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDI
4、NATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND US
5、ER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 In premises networks G.9900G.9999For further details, please refer to the list of ITU-T Recommendat
6、ions. Rec. ITU-T G.9902 (2012)/Amd.1 (03/2013) i Recommendation ITU-T G.9902 Narrowband orthogonal frequency division multiplexing power line communication transceivers for ITU-T G.hnem networks Amendment 1 Summary Amendment 1 to Recommendation ITU-T G.9902 (2012) contains: various clarifications an
7、d corrections the support for an annex with an ARIB bandplan for the Japan region. History Edition Recommendation Approval Study Group 1.0 ITU-T G.9902 2012-10-29 15 1.1 ITU-T G.9902 (2012) Amd. 1 2013-03-16 15 ii Rec. ITU-T G.9902 (2012)/Amd.1 (03/2013) FOREWORD The International Telecommunication
8、Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff question
9、s and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on
10、 these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the
11、expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or appl
12、icability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with
13、the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applica
14、bility of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected by patents, which may be required to implement t
15、his Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2013 All rights reserved. No part of this publication may be reproduced, by any means wh
16、atsoever, without the prior written permission of ITU. Rec. ITU-T G.9902 (2012)/Amd.1 (03/2013) 1 Recommendation ITU-T G.9902 Narrowband orthogonal frequency division multiplexing power line communication transceivers for ITU-T G.hnem networks Amendment 1 NOTE Any modifications introduced by this am
17、endment are shown with revision marks. Unchanged text is replaced by ellipses (). Some parts of the unchanged text (clause numbers, etc.) may be kept to indicate the correct insertion points. 1) Changes to clauses 8.3.5 and 8.4.2.7 Make the changes indicated below for clauses 8.3.5 and 8.4.2.7. 8.3.
18、5 Channel interleaver The channel interleaver interleaves a block of BIbits (see clause 8.3.3, clause 8.3.4), based on the number of subcarriers per symbol frame that are loaded bits multiplied by k, which stands for modulation used (k = 1 for 1-bit modulation, k = 2 for 2-bit modulation, etc.), den
19、oted in this section by m. For the payload, these subcarriers are those identified in the TM field of the PFH, except the subcarriers from the PMSC, RMSC (unless BAT type 0 is used), and PSC sets. For the PFH, these are all subcarriers from the RMSC set and all subcarriers from the SSC set, except t
20、hose from the PSC set (see clause 8.4.2.1, clause 8.4.2.2, clause 8.4.2.5). For the payload encoder BI= B0, for the PFH encoder BI= NSIkH. The interleaver is only defined for values of BIthat are multiples of m, i.e., n = BI/ m is an integer. The B0I input bits shall be written into the permutation
21、matrix with n rows and m columns. The insertion of the bits into the matrix shall be performed using the equations below: q = floor(p/(k m) r = mod(p,k m) i = floor(r,k) j = kq+mod(r,k) j = floor(p/m) i = mod(p, m) where: p is the sequential number of the bit in the input sequence (input vector), in
22、 the range from 0 to BI-1 k is the modulation used (k=1 for 1-bit modulation, k=2 for 2-bit modulation, etc.) i is the index of the column and j is the index of the row in the permutation matrix in the range from 0 to m-1 and from 0 to n-1, respectively (m columns by n rows). Figure 8-14 shows the i
23、nsertion of the bits into a matrix when the equations are used with k=2. Each box in the Figure 8-14 represents a bit. The number in the box indicates the position of the bit in the input bit sequence (input vector) and in the output bit sequence (output vector), respectively. 2 Rec. ITU-T G.9902 (2
24、012)/Amd.1 (03/2013) Rec. ITU-T G.9902 (2012)/Amd.1 (03/2013) 3 Figure 8-14 Order of writing in and reading out of the permutation matrix The entries of the n m matrix shall be permuted. The relation between input and output bit indices shall be determined from the following equations: for the bit w
25、ith the original position (i, j), where i = 0,1,., m 1 and j = 0,1,., n1, the interleaved bit position (I, J) shall be: J = ( j n_j + i n_i ) mod n I = ( i m_i + J m_j ) mod m where m_i, m_j, n_i, and n_j are selected based on the values of m and n, under the constraint that m_i, m_j, n_i, n_j 2 GCD
26、(m_i,m) = GCD(m_j,m) = GCD(n_i,n) = GCD(n_j,n) = 1 4 Rec. ITU-T G.9902 (2012)/Amd.1 (03/2013) where GCD stands for the greatest common divisor. The values of n_i, n_j and m_i, m_j shall be computed as follows: For a given value of n, all the co-prime numbers of n except numbers 1 and 2 shall be sort
27、ed in ascending order; then, n_i shall be the first co-prime element above n/2 in that co-prime number set, and n_j shall be the next element to n_i. In case there are not enough co-prime numbers to satisfy the rule, all the existing co-primes (including 1 and 2) should be used to form a set, n_i sh
28、ould be the second number in the set, while n_j should be the third number. In case there are only two numbers in a set, n_i should be the first number and n_j should be the second number. Same steps shall be applied to compute m_i and m_j, for a given value of m. The following is an example for co-
29、prime selection for n = 8, m = 10: Since n = 8, the co-prime numbers for 8 except 1 and 2 are: 3, 5, 7. The first co-prime number above n/2 is 5, so n_i = 5; and the next co-prime is 7, so n_j = 7. Since m = 10, the co-prime numbers for 10 except 1 and 2 are: 3, 7, 9. The first co-prime number above
30、 m/2 is 7, so m_i = 7; and the next is 9, so m_j = 9. After permutation, bits shall be extracted from the permutation matrix in the same order that they were written into the matrix. An example for 2-bit modulation (k=2) is given in Figure 8-14. 8.4.2.7 Modulation of pilot subcarriers Pilot subcarri
31、ers shall be modulated with 2-bit modulation where the bits shall be generated using an LFSR initialized with all ones at the beginning of the PFH, prior to the transmission of the first PSC. The generation polynomial shall be as defined in clause 8.4.2.6. The modulation of the PSC shall start from
32、the first PFH symbol; each subcarrier from the PSC set (in ascending order) shall be modulated with the two bits which are the LSBs of the LFSR, d0, and d1(as presented in Figure 8-17), using the 2-bits constellation mapping defined in clause 8.4.3. Rec. ITU-T G.9902 (2012)/Amd.1 (03/2013) 5 2) New
33、Annex E Add the following new annex. Annex E Regional requirements for Japan (This annex forms an integral part of this Recommendation.) E.1 Introduction Clause A.1.3 of ITU-T G.9901 defines the parameters and requirements for the ARIB bandplan. The requirements for the ARIB regional annex shall fol
34、low the FCC requirements, with the modifications given below. E.2 Physical layer (PHY) specification The PHY specification shall be in accordance with the bandplan specification defined by clause A.1.3 of ITU-T G.9901 and clause 8 of this Recommendation. E.3 Data link layer (DLL) specification The D
35、LL specification shall be in accordance with clause 9 of this Recommendation, with the following changes: IFG_MIN shall be set to 25 ms except for retransmissions where IFG_MIN shall remain unchanged; The maximum number of re-transmissions (MaxRetransmissions) shall be limited to being less than or
36、equal to 7. Printed in Switzerland Geneva, 2013 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D General tariff principles Series E Overall network operation, telephone service, service operation and human factors Series F Non-telephone telecommunication services S
37、eries G Transmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Series K Protection against interference
38、Series L Construction, installation and protection of cables and other elements of outside plant Series M Telecommunication management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specifications of measuring
39、equipment Series P Terminals and subjective and objective assessment methods Series Q Switching and signalling Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects and next-generation networks Series Z Languages and general software aspects for telecommunication systems
