1 (2006) 2 2 3 4 5 9 9 9 10 11 11 11 12 32 37 43 48 55 58... (ATM) (IP)................................. FWA... - -... (CSMA/CA) -...... 0 - -...... -... FWA - 1.6 2.6 3.6 4.6 5.6 6.6 1 2 3 4 5 6 7 1 2 3 4 5 6
2 1. (ATM) (IP)... (ATM) (IP) (FWA). (CoS) (QoS)... ATM IP FWA FWA PHY.ITU-T Y.1541 ITU-T I.356.ATM IP (PHY) ITU-T Y.1541 ITU-T Y.1540 ITU-T I.356.IPTD IP.(CER) (CLR) (PHY) (SESR) ITU-R F.1400 ) ITU-R F.1668.((PSTN) ATM IP. ATM IP FWA FWA ATM IP.(RLANs).ATM IP FWA (ATM) (IP) 2 ATM IP.. (P-MP) (P-P)..GHz 20 FWA.. (PSTN).
3.ATM IP...... (FWA). FWA (. FWA.(SDH) ATM (. (NWA) (RLAN) ITU-R M.1450 ITU-R F.757.. 3 FWA Mbit/s ATM IP (NWA) (RLANs). MAC IP 6.ATM IP ITU-T.ATM. ( (
4...km 27 500.2004 GHz 17.GHz 66. IP.. P.862.(MOS-LQO). ISDN ATM. E... (PCM).kbit/s 6,3 5,3 kbit/s 8.(CS-ACELP) 2 :1.(HIPERMAN) :GHz 11 (HIPERACCESS).(PHY) 4 ITU-R F.757 ITU-R M.1450 ITU-R F.1668 ITU-R F.1704 ITU-R F.1763 ITU-T ITU-T Y.1540 ITU-T Y.1541 ITU-T P.800 ITU-T P.862 ITU-T I.356 ITU-T G.107 ITU-T G.113 ITU-T G.114 ITU-T G.711 ITU-T G.723.1 ITU-T G.729 ETSI TS 101 761-1 v1.3.1 ETSI TS 101 856 v1.1.1 ETSI TS 101 999 v1.1.1
5 IEEE standard for local and metropolitan area networks Specific requirements Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications Amendment 1: High-speed physical layer in the 5 GHz band. IEEE standard for local and metropolitan area network Specific requirements Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications. IEEE standard for local and metropolitan area networks Specific requirements Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications Amendment 4: Further higher-speed physical layer extension in the 2.4 GHz band. IEEE standard for local and metropolitan area networks Part 16: Air interface for fixed broadband wireless access systems. ARIB STD-T70 v1.0 Low power data communication systems/broadband mobile access communication system (HiSWANa). Design and considerations for traffic class expediting and dynamic multicast filtering, IEEE Std 802.1D Annex H, IEEE, 1998. http://www.ietf.org/html.charters/mpls-charters.html http://www.ietf.org/html.charters/diffserv-charter.html http://www.ietf.org/html.charters/rsvp-charter.html Wireless medium access control (MAC) and physical layer (PHY) specifications: Medium access control (MAC) enhancements for quality of service (QoS), IEEE std 802.11e/D1, March 2001. INOUE, Y., SAITOH, S., IIZUKA, M. and MORIKURA, M. [December 2000] A fair data transfer method by using a CoS control mechanism for fixed wireless access systems, The 2000 International Conference on broadband wireless access systems, p. 19-25. KAGAMI, O., OTHA, A. and HOJO, H. [November 2002] Development of compact wireless access equipment for an AWA system based on HiSWANa standard, NTT Rev., p. 49-53, Vol. 14, No. 6. TTC Standard JJ-201.01 [2003] A method for speech quality assessment of IP telephony. ETSI TR 101 329-7 End-to-end quality of service in TIPHON systems; Design guide for elements of TIPHON connection from an end-to-end speech transmission point of view. MASUDA, M. and ORI, K. [November 2001] Network performance metrics in estimating the speech quality of VoIP, IEICE APSITT2001, p. 333-337. ICHIKAWA, T., et. al., Approximation of characteristics of CSMA/CA based on IEEE 802.11 standard, B-5-186, Proceedings of the 2003 IEICE Society Conference. (Arbitration inter-frame space) (Acknowledge) (Automatic repeat request) (Asynchronous transfer mode) 5 : (Broadcast channel) ACK AIFS ARQ ATM BC
6 (Block convolutional code) (Best effort) (Binary exponential backoff) (Broadband wireless access) (Bit error ratio) (Class based queuing) (Base station) (Constant bit rate) (Cell delay variation) (Cell error ratio) (Cell loss ratio) (Cell misinsertion ratio) (Class of service) (Carrier sensing multiple access with collision avoidance) (Cell transfer delay) (Contention window minimum) (Demand assign multiple access) (Contention window) (Differentiated service) (Distributed coordination function inter frame space) (Data link) (Differentiated service) (Dynamic slot assignment) (Enhanced distributed coordination function) (Frame check sequence) (Frequency division duplex) (Frequency switched division duplexing) (Forward error correction) (First in first out) (File transfer protocol) BCC BE BEB BER BS BWA CBR CBQ CDV CER CLR CMR CoS CSMA/CA CTD CW CWmin DAMA DiffServ DIFS DL DS DSA EDCF FCS FDD FSDD FEC FIFO FTP
7 (Fixed wireless access) (Go-Back-N method) N (Guaranteed bit rate) (Hybrid coordination function) (Header error control) (High performance radio ACCESS network) (High performance radio metropolitan area network) (Institute of Electrical and Electronics Engineering) ACCESS (Hypothetical reference path) (Internet engineering task force) (Internet protocol) (IP packet delay variation) IP (IP packet error ratio) IP (IP packet loss ratio) IP (IP packet transfer delay) IP (International Telecommunication Union Radiocommunication Sector) (International Telecommunication Union Telecommunication Standardization Sector) (Loss cell outcome) (Label distribution protocol) (Label switching router) (Media access control layer) (Multipoint-to-multipoint) (Multi-protocol label switching) (Multicast) (Measurement point) (Mean opinion score) (Negative Acknowledge) (Non-real-time polling service) (Orthogonal frequency division multiplexing) (Peak cell rate) FWA GBN GBR HCF HEC HIPERACCESS HIPERMAN HRP IEEE IETF IP IPDV IPER IPLR IPTD ITU-R ITU-T LCO LDP LSR MAC MC MP MP-MP MPLS MOS NAK nrtps OFDM PCR
8 (Protocol data units) (Payload header suppression identifier) (Packet loss concealment) (Packet loss probability) (Packet loss probability in network) (Physical slot) (Packet loss probability in jitter absorption buffer) (Per-hop behaviour) (Physical layer) (Point-to-point) (Point-to-multipoint) (Perceptual evaluation of speech quality) (Public switched telephone network) (Quality of service) (Resource reservation protocol) (Real-time polling service) (Request to send/clear to send) (Synchronous digital hierarchy) (Rating factor) (Service level agreement) / (Single carrier) (Space division multiple access) (Short inter frame space) (Tag control information) (Time division duplex) (Time division multiplex) (Time division multiple access) (Telecommunication Technology Committee) (Selective repeat) (Traffic category) (Type of service) PDU PHSI PLC PS P pl P pln P plb PHB PHY P-P P-MP PESQ PSTN QoS R RSVP rtps RTS/CTS SLA SC SDH SDMA SIFS SR TC TCI TDD TDM TDMA ToS TTC
9 (Unspecified bit rate) (Unsolicited grant service) (User network interface) (Voice over Internet protocol) (Wide area network) (Weighted fair queuing) (Weighted round robin) UBR UGS UNI VoIP WAN WFQ WRR 6 1.6 1. 1 (1) Conveyed signal Adaptive (4-, 16-, and 64-QAM) (2) Adaptive (BPSK, 4-, 16-, and 64-QAM) (2) Adaptive (BPSK, 4-16-, 64- and 256-QAM) (2) Presettable (4- and 16-QAM) CCK (QPSK) DSSS (BPSK, QPSK) Adaptive (4-, 16-, and 64-QAM) (2) Adaptive (BPSK, 4-, 16-, and 64-QAM) (2) Adaptive (BPSK, 4-, 16-, 64- and 256-QAM) (2) Presettable (4- and 16-QAM) TDM-TDD/FDD TDMA-TDD/FDD OFDMA-TDD/FDD DAMA-TDD/FDD CSMA/CA DSSS-OFDM TDM-TDD/FDD TDMA-TDD/FDD OFDMA-TDD/FDD DAMA-TDD/FDD.. (QoS) (CoS) 2.6.... 1. (1) (2)
10 3.6. ITU-T Y.1541 ITU-T Y.1540 IP IP.ATM IP. IP IP 1 IP IP.ITU-T Y.1541 1 FWA FWA FWA AG FWA. ( ) FWA.FWA. TDMA CSMA/CA FWA.FWA IP 1.3.6 (RTS/CTS) CSMA/CA.(2 ) IPTD. TDMA. (RTS/CTS) CSMA/CA IPTD.(3 ) IPTD
11 IP 2.3.6.(BEB) CSMA/CA FWA. IPDV.IPDV.IPDV.. TDMA.CSMA/CA IPDV IPTD.(4 ) IP 4.6..( ). FWA 5.2003 JJ-201.01 5.6...(DAMA) (TDD) (SDMA).. (MAC) 6.. FWA 6.6 / ARQ FWA.. FWA 7
12 1 1. /..IEEE 802.11.CSMA/CA TDMA MAC ETSI-BRAN HIPERMAN. OFDMA.MMAC-HSWA HiSWAN IEEE802.16-2004 HIPERLAN HIPERACCESS. /....2 5 4. 6.. 2 1.2.(2 )...... 1.2.2.. (BS)... 2.2
13 2 ( ) 1 ( ) 2 ( ) 3 Rap 2058-02 2.2.2... /..... 3.2.2.....3 IEEE 802.ID H2... 4.. CSMA/CA.
14. 3 MAC VLAN :ERIF 4 1 2
15 3.2 1.3.2....... 2.3.2 /.... 3 1.3 /... 2.3.....5..
16 5 1.2.3.......... (CBQ).... 4.2.3. (WFQ). 3... 3 2 2. 2.2.3 3.2.3 3.3
17 2 IEEE 802 Committee IEEE 802.1D Annex H2 Tagging IEEE 802.1D Annex H2 Layer 2 IETF Label Switching MPLS IETF Use of DS field (IP ToS field) DiffServ Layer 3-4 IETF RSVP signalling RSVP.. 2 3......(DiffServ) (DiffServ) 2.3.3.(DiffServ) IPv4...(PHB)..SLA 1.3.3
18 3.3.3... 2 CSMA.. 6 6 A B C B A C MAC.. 4.3.3 1.4.3.3 7.. MAC.
19... 7 ( ) 2 (2 3 ) 2.4.3.3. 8.2 3.. (MAS).2 3
20 8 () 3 ( ) (2 3 ) 3.4.3.3. (MAC)... 4 CSMA/CA CSMA. CSMA/CA IEEE 802.11 LAN.LAN. CSMA/CA. CSMA/CA CSMA/CA.CSMA/CA. 1.4
21 CSMA/CA 2.4 CSMA/CA..(DIFS).... N.." ".... CSMA/CA 3.4 CSMA/CA... CSMA/CA. CSAMA/CA. CSMA/CA.9 1 9 2.T A 9.T B.T B T A. CSMA/CA....
22 1.4.4 CSMA/CA IEEE 802.11 CSMA/CA.10. CSMA/CA...DIFS. CW " ".. SIFS ACK. 4.4 9 CSMA/CA ( ) ( ) 1 2 T = B
23 10 IEEE 802.11 DIFS DIFS (EDCF) 2.4.4. CSMA/CA.IEEE 802.1D H TC (TC) EDCF.IEEE 802.11TGe MAC 11 EDCF (TC) CSMA/CA EDCF.EDCF EDCF.. 11 IEEE 802.11e MAC i j k l
24 3.4.4..CW 0. 1 2 CW CWmax CWmax CW WCmax CW. queue i: 0~Cwi : CW EDCF.CWj CWi j i.queue j: 0~CWj. (AIFS) 4.4.4 EDCF.DIFS CSMA/CA j i.12 DIFS AIFS..AIFS[j] AIFS[i] (IEEE 802.1D Annex H2) CoS 5.4 IEEE 802.1D Annex H2...MAC 6 5 4 3. AIFS 12
25 IEEE 802 LANs 3 " ". ( ) ms 100 ms 100 (BK) (BE) (CL) (NC) (EE) (VI) (VO) 1 2 ( ) 0 3 4 5 6 7.(WRR) (WFQ) IEEE 802.1D Annex H2. 4 4 {BK, BE, EE, CL, VI, VO, NC} {BK, BE, EE}, {CL, VI, VO, NC} {BK, BE, EE}, {CL, VI}, {VO, NC} {BK}, {BE, EE}, {CL, VI}, {VO, NC} {BK}, {BE, EE}, {CL}, {VI}, {VO, NC} {BK}, {BE}, {EE}, {CL}, {VI}, {VO, NC} {BK}, {BE}, {EE}, {CL}, {VI}, {VO}, {NC} 1 2 3 4 5 6 7
26 5. /..... 2.5.. 3.5. 5 1.5 2.5 5 / / E-mail, FTP With GBR or UBR 1 Image With CBR 2 Telephone, real-time image No CBR 3 (UBR) (GBR) 1.... 3 2. 3... 3.5
27............. ( ). : (1) Bandwidth effective = Th average + ϕ* ( THmax THaverage) :Bandwidth effective :Th average :TH max : ( ). 1 0 ϕ ϕ.. ϕ.(2) 1 (2) Bandwidth = Th = TH effective average 13 ϕ. 5 1. max
28.. 13.. (CBR).. : (3) Bandwidth effective = Th average + ϕ* ( THmax THaverage) (1) (3) : (3) ϕ ϕ (4) (5) (6) 0 = ϕ 1 > ϕ > 0 1 = ϕ Bandwidth effective = Th average Th < Bandwidth < TH average effective Bandwidth effective = TH max max
29... :. (7) Bandwidth effective = θ * θ2 * Thaverage + θ1 * θ2 * ϕ* ( TH TH 1 max average ) 1 0 θ 2 1 0 θ 1.... R i. (8) BW effective R1 (Priority1) = R2 (Priority 2) R3 (Priority 3) (DSA) 1.4.5 (TDMA). (MAC)..TDMA-TDD/DSA (MAC) 14.(DSA). 4.5
(MAC) 30 14 TDM-TDD/DSA a b.15 2.4.5 15 1 2 3 4 ( ) BC/MC UC ( )
31 :1... :2.. (MC) (BC) :3. 2 1... :4. 3 1..... 6. 6 6 / (1 (2 ETSI-BRAN HIPERACCESS ETSI-BRAN HiperLANETSI-BRAN HIPERMAN MMAC-HSWA HiSWAN IEEE 802.16-2004 IEEE 802.11
32 2 (CSMA/CA) RLAN ) CSMA/CA.((HCF). 1 (9) : (T m ) ( S m S m = T m L ip 8 + SIFS + T a ) 2 (10) T m = n= 0 n ( 1 p ) p ( A+ nb) m m p = A+ B m 1 p m Ack (bytes) :m : L ip :T d :T a : : (10) (9) (CW min ) -. -. CW min (6M 24M 54M ) CSMA/CA 4 3.( 11M) CSMA/CA 3 SS. 7 VoIP T m (T m ) 16 16.M.
33 T m. BEB. m 7 CSMA/CA (11M mode, long preamble) 10 50 20 31 200 364 202 None CSMA/CA (54M, 24M, 6M mode) 16 34 9 15 200 56 (54M) 100 (24M) 340 (6M) 24 (54M) 28 (24M) 44 (6M) None SIFS (µs) DIFS (µs) SlotTime (µs) CWmin (bytes) Td (µs) Ta (µs) (6M 24M 54M ) 16 CSMA/CA ( 11M) (ms) m
34. (10) (9) (VoIP) m-1. (10). (10) 4 (11) T m( S) = n= 0 n ( 1 p ) p ( A + nb ) m m ( S) ( L) = A ( S) + B ( L) pm 1 p m :T m(s) : A B ( S) ( L) = DIFS + CW = T d( L) min + SIFS + T SlotTime/2+ T a (m (S) + m (L) =).(1=) + DIFS + CW d( S) min SlotTime/2 :m :m (L) :m (S).(11) 8.7 CSMA/CA (11M mode, long preamble) 200 1 500 1 309 364 8 CSMA/CA (54M, 24M, 6M mode) 200 1 500 248 (54M) 536 (24M) 2 072 (6M) 56 (54M) 100 (24M) 340 (6M) (bytes) (bytes) Td (L) (µs) Td (S) (µs) T m(s). (T m(s) ) 17 16 (m=m (S) +m (L), here, m (S) =1). 17
35 = m (544 : T m 3 (12) ) CSMA/CA 19 18-3 10 1. 8 5 ( S),1e 3 3 Tm( S),1e 3 A( S) B( L) + 1 log pm 9 3-10 1 CSMA/CA (54M mode) CSMA/CA (11M mode, long preamble). 9 3 = m ms 7,5 ms 33,5 m (L) = 2 m (S) = 1 5 = m ms 15,8 ms 65,9 m (L) = 4 m (S) = 1 8 = m ms 32,2 ms 122,1 m (L) = 7 m (S) = 1 17 (6M 24M 54M ) CSMA/CA ( 11M ) CSMA/CA (ms) m
(54M CSMA/CA) 36 18 (ms) 19 ( 11M CSMA/CA) (ms)
37 3.IEEE 802.16-204. / 1. / (rtps) (UGS).(BE) (nrtps) (UGS).. T1/E1.MPEG (BE).. (UGS).VoIP.. :. 20. /. 1 2
38 UGS 20 21....ms 1.... k 2 = i i (mini-slots).7 k 21 3 0 n - 1 1 - j 1 - j j 1 + j 2 + j
39.. 10. :.(kbit/s 64 ) ITU-T G.711 MAC PDU MAC TCP/IP. 381 BCC Reed Solomon. 234.1 540 QPSK. 20 000.ms 1.MHz 25 QPSK (BE) nrtps rtps..mpeg. 3:1 /. 5 000.. 4 - - - -
40 10 G.711.( 4) bytes 234 bytes 160 bytes 40 bytes 24 bytes 2 bytes 2 bytes 6 QPSK BCC Reed Solomon 2 bytes 254 (24 16) 16 0,25 MHz 25 Mbaud 20 Mbit/s 40 Ms 1 20 000 5 000 (K+R) MAC PDU VoIP payload - IP - - FCS - PHSI - MAC - FEC BCC VoIP.ms 20 VoIP.ms 20 VoIP VoIP ( ) 40 22.ms 20. t 0 VoIP VoIP. VoIP VoIP.SS VoIP.t 1 UL_MAP SS.. (t 1 - t 0 ) - - -
41 22 VoIP.VoIP (1 m) -. D m m m 1 ( 1)! j m ( N j 1)! Dm ( N m+ 1) di (13) N! ( m j 1)! j= 1 i= 1 1 j m 1 : (40 =) ms 20 VoIP :N.i (1 i) :d i ms 0,92 = d even ms 0,08 = d odd. 33.(13) D m 23 24 VoIP.ms 20.(13). VoIP VoIP (TDMA).IEEE 802.16-2004. IP 5
42 23 (ms) VoIP m m VoIP
43 24 m-th VoIP m 0 4 0 IPTD.ITU-T Y.1541 III. (IPDV) IP (IPTD) IP. 25 : DV(AN) D(AN) D(AN) = D(FWA) + D(BH) = D(s) + D(air) + D(b) + D(BH) DV(AN) DV(FWA) + DV(BH) = DV(s) + DV(air) + DV(b) + DV(BH) 1
44.(backhaul) 25. IP IP. / :. DV(BH) D(BH) DV(FWA) D(FWA).DV(AN) DV(air) D(AN) D(air) DV(AN) D(AN) D(AN) D(FWA) =D(s) + D(air) + D(b) DV(AN) DV(FWA) =DV(s) + DV(air) + DV(b) 25
45-2 : IP ITU-T Y.1541 (N I * D I ) + (N C * D C ) + (N D * D D ) + (N A * D A ) + (R km * 0.005) (ms) IPTD D km 1,25 * = R km : N I N C N D N A 1.III.ITU-T Y.1541 III D I D C D D D A III 1.III.ITU-T Y.1541 D km R km - - - -.26. IPDV (HRP) UNI-UNI :. -.ITU-T Y.1541 III 3.III HRP III. 200.T1 VoIP 1 500 Km 5087,5 Km 4 070.ITU-T Y.1541 (HRP) 11.UNI-UNI IPDV IPTD HRP IP 2 IP 1.ITU-T Y.1541 III 2.III - - - -
46 DV(AN) D(AN) IPDV IPTD 3.6 1.. D(NA). 2 FWA CSMA/CA. ms 10.ms.(ETSI TR 101 177 V1.1.1[1] ) ETSI HIPERACCESS (ms 10) ms 16 3 10 1 2. (5 = m 54M ) CSMA/CA 26 ( )
47 11 ( CSMA/CA ) Max IPDV (ms) IPDV/Unit (ms) Average IPTD (ms) IPTD/Unit (ms) Unit km 4 070 25 km 5 087,5 16 1 10 1 1 FWA 28 20 1 16 3 6 3 16 3 3 3 10 3 4 3 10 3 2 3 1 1 2 1 Access, N A Distribution, N D Core, N C Internetwork GW, N I 34 24 2 16 3 12 3 16 3 3 3 10 3 8 3 10 3 2 3 1 1 4 1 Access, N A Distribution, N D Core, N C Internetwork GW, N I 0 15 Non-IP Net 78 94 UNI-UNI Total (ms) 50 100 ITU-T Y.1541 ms 94 UNI-UNI IP ms 78 UNI-UNI IP.ms 100..(ms 50 ) ITU-T Y.1541. IPDV ms 62 (DV(AN)) ms 16 ms 78 - IP ms 62 -.ITU-T Y.1541 III III.2 UNI-UNI ms 62 ITU-T Y.1541 -.. CSMA/CA UNI-UNI 11.IP IP (TDMA)
48 5 1 (VoIP).. VoIP.. VoIP.. VoIP 2.ITU-T Y.1541 ITU-T Y.1540 IP ITU-T Y.1541 ITU-T Y.1540..IP VoIP... (MOS). ITU-T P.800... ITU-T P.800 ITU-T G.107 E : R.R. (14) R = R 0 I s I d I e, eff + A : :R 0 :I s :I d. :I e, eff. A. R JJ-201.01
49. R. 3 E. E 12 1.3.12 ms 500 ms 500 ms 1 000 ms ms ms Ta Tr Ta T Tr Ta. ms 500....E 2.3... (P pl ).. ( ) P pln (P plb ) (P pln ) P pl. P plb. 20.13 P pln P plb. E.
50 13 20 % P pl " JJ-201.01 P plb APSITT2001 [2001 November] k ORI M MASUDA) ". (P.333-337 IEICE ITU-T G.711 R UNI-UNI. ITU-T G.107 ITU-T G.723.1 ITU-T G.711.kbit/s 64.ITU-T G.711. 14 ITU-T G.711 14 4 1.4 ms 80 PLC " " (PLC ) ms 90 (PLC ) ms 80 (ms) 40 40 10 0 80 or 90 I/G.711. 160 TCP/IP 40 200 VoIP.ms 20 ms 78 IP.IP ITU-T Y.1541.ms 80 4 11..ms 40.ms 90 ms 80. ms 10 (PLC)
51 /.. VoIP VoIP...ms 150 ITU-T G.114 DV(AN) D(AN). FWA : 2 6 (UNI-UNI) IPDV IPTD -.DV(AN) D(AN) FWA. FWA DV(AN) D(AN) -. CSMA/CA FWA - ( 1 500) (m 1) m 1 - (m ) (FTP).VoIP ( 200) ). 9 - (UNI-UNI) IP.( 2.4 D(total) : (15) PacketFormation = 40 ms DV ( AN) + DV ( IP Net 1) + DV DeJitterBuffer 2 DV ( AN) DV ( FWA) = A DV ( IP DV ( IP Net 1) = 28 ms Net 2) = 34 ms ( S) ( IP Net 2) B ( L) 3 log p m + 1 PLC 10 ms = 0 (with PLC) (without PLC) D( total) = IPTD( UNI UNI ) + CodertDelay = D( AN ) + D( Route) + D( IP Net 1) + D( IP Net 2) + D( NonIP Net) + CoderDelay
52 (16) p D( AN ) D( FWA) A m ( S) + B( L) 1 pm : 5 ms 25 = D(Route) ms 20 = D(IP Net 1) ms 24 = D(IP Net 2) ms 15 = D(NonIP Net) (14) (13) B (L) A (S) : D(total) 3 B( L) 2 p 3 ( ) ( ) 1 + 165 (or 155) 2 2 m D total A S + 1 log pm pm.m 27.CSMA/CA 54M.ms 200 VoIP 27 (ms) m
53 ms 165. 27 ms 165 m.(fwa) m. :.(FWA) IP :D(FWA) -. DV(FWA) :D(Buff) -.D(FWA) D(Buff) R m 2.4 R. ITU-T G.107 R R m 2.4.m. 3,0 1,0 0,1 0 Ppl.15 Ppl Bpl Ie Ie-eff.ITU-T G.107.(Tr)/2 R = (Ta) = (T) m. (24M ) 29 (54M ) 28.24M R m R 15 3.4 Ie-eff 0 0,4 3,6 10,1 0 2,2 17,9 39,0 Ppl (%) 0 0,1 1,0 3,0 0 0,1 1,0 3,0 Bpl 25,1 4,3 Ie 0 0 PLC G.711 I Coder G.711 G.711 ITU-T G.711 %0,1 Ppl..%70 R R.
54 28 (54M CSMA/CA) R (%) R m 29 (24M CSMA/CA) R (%) R m
55 6 1..30.. (CDV)..... ).. (P-MP : ) -.(. - 2 ( / ) ) /. : 30.. / ("*" ) 3 ) " " ( 10 ) PCR.( (PCR). ( ). PCR.
56...31...VBR..32.(CDV) ) (CDV).( ( (
57 30. = * 31 ( ) = * 32 ( ) = * ( )
58 7 FWA 1 1.1. (ARQ)....... (ATM). ( ) (ATM). 1 : 9 10 ms 500 7 10 ms 10 :. 7 10 ( ) db 1-0,5 9 10 ) ). ( 1998 (ATM Forum BTD-WATM-01.06) 1
59.. ( ).. ( =.(ARQ).....(GHz 18 ) ( ) ( P-P P-MP ) ATM ( ).. 2.1 - n. (b 33 (a 33...(c33 ). 34.. N output N output N output = 1..( )..
60 34... 3.1 ). (. (NAK). ).( 100 %1 33
61 GBN 2 34 N output (%) ( ) 3 2 :.. :..( ) ( )..... OHTA, A. et al. [May 1998] PRIME ARQ: A Novel ARQ Scheme for High-speed Wireless ATM Design, implementation and performance evaluation, VTC'98, p. 1128-1134. 2
62 4.1. (rt-vbr) (CBR) (CTD).. 7 10 ms 10 rt-vbr CBR (CLR). 8 10 ITU-T I.356 / (FEC).(ARQ)...( ) 2. ITU-R 210/9.ITU-T I.356 (HEC) (ATM). (LCO) (CLR) (CMR)..... 1.2 2.2
63........(modulo-4) 4 90. 35 35 3.2. 36.. 37.
64 37 / 38. 38..QPSIC 38 320 214 108 2 319 213 107 1