BI GING H THNG THNG TIN HNG HI (CH13207) TS. Trn Xun Vit i hc Hng hi. H thng thng tin hng hi c cp trong mn hc ny gm : - H thng GMDSS, v- H thng non-GMDSS V th ni dung chnh ca mn hc gm 3 vn chnh : -Tng quan v GMDSS (GMDSS basic) -Quy hoch GMDSS (GMDSS update) -Cc H thng non-GMDSS (GMDSS extend)

V cng mn hc nh sau : Chng 1 : C bn v GMDSS 1.1 GMDSS 1.2 DSC 1.3 NBDP 1.4 INMARSAT 1.5 COSPAS-SARSAT 1.6 MSI Chng 2 : Quy hoch h thng GMDSS 2.1 Thng t GMDSS.1/Circ.13 2.2 Quy hoch chung 2.3 Quy hoch vng bin A1 2.4 Quy hoch vng bin A2 Chng 3 : H thng Inmarsat bng rng 3.1 H thng I4 3.2 FBB Chng 4 : Cc dch v thng tin non-GMDSS khc Ti liu tham kho : -GMDSS handbook (CopyrightIMO 2001) -GMDSS.1/Circ.13 (GMDSS Master Plan) -Inmarsat maritime communications handbook (Issue 4) -FleetBroadband Best Practices Manual (Inmarsat.com) -Bi ging GMDSS (HHH) Chng 1TNG QUAN V GMDSS (GMDSS Basic) I. KHI QUT V GMDSS 1.1. GMDSS ? * GMDSS : Global Maritime Distress and Safety System * Ch th : -H thng GMDSS do IMO xng v pht trin - C s hp tc ca nhiu t chc quc t khc, nh : ITU, INMARSAT,COPAS - SARSAT... * Thi hn:- Ln u tin c thng qua di dng sa i v b sung SOLAS 74 vo thng 10 /1988 ch yu sa i . 4: Radio Comnunication, nn cn gi l SOLAS74/88. - GMDSS bt u c hiu lc (tng phn) 1.2.1992 GMDSS bt u c hiu lc (y ) 1.2.1999 Sau nm 1999 h thng GMDSS tip tc c hon chnh b sung * Cc cng c quc t GMDSSolas 74/88 (. 4: Radio Communication) Cc ngh quyt ca IMO c lin quan (IMO resolutions) Cc khuyn ngh ca IIUc lin quan (ITU recommendations) Cc thng t ca cc t chc c lin quan (Circulars) 1.2. CC CHC NNG THNG TIN GMDSS * C th chia cc chc nng thng tin GMDSS thnh 3 nhm chc nng : - Nhm chc nng phc v mc ch tm kim, cu nn trn bin (Distress) - Nhm chc nng phc v mc ch an ton hng hi (Safety) - Nhm chc nng thng tin cng cng (Public) * Cc chc nng c th (9) th hin trong . 4 SOLAS74/88 Every ship, while at sea, shall be capable: .1 of transmitting ship-to-shore distress alerts by at least two separate and independent means, each using a different radiocommunication service; .2 of receiving shore-to-ship distress alerts; .3 of transmitting and receiving ship-to-ship distress alerts; .4 of transmitting and receiving search and rescue co-ordinating communications; .5 of transmitting and receiving on-scene communications; .6 of transmitting and receiving signals for locating; .7 of transmitting and receiving maritime safety information; .8 of transmitting and receiving general radiocommunications to and from shore-based radio systems or networks; and .9 of transmitting and receiving bridge-to-bridge communications. Gii thch : - 6 chc nng t 1 n 6 thuc nhm chc nng distress Distress alert (bo ng cp cu) theo cc hng : ship-to-shore (Distress call) shore-to-ship (Distress relay),vship-to-ship. Thng tin tm kim cu nn: SAR communications. Thng tin hin trng : on-scene communications. Thng tin xc nh v tr : locating. - 2 chc nng (7 v 9) thuc nhm chc nng Safety Thng tin an ton hng hi MSI. Thng tin t bung li ti bung li(Bridge-to-bridgecommunicationsmeanssafetycommunicationsbetweenshipsfromthe positionfromwhichtheshipsarenormallynavigated),cthhiulthngtinVHFv AIS. - Chc nng th 8 l thng tin cng cng (General or public) 1.3. CC C TRNG C BN CA GMDSS. * Cc vng bin- Vng bin A1 : L vng bin nm trong tm hot ng ca t nht mt trm i b VHF thoi c trc canh lin tc DSC. Thng thng mi trm VHF c vng ph sng vi bn knh khong 25 - 30 hi l. - Vng bin A2 :L vng bin nm ngoi vng A1, nhng nm trong tm hot ng ca t nht mt trm i b MF thoi c trc canh lin tc DSC. Thng thng mi trm MF c vng ph sng vi bn knh khong 150 - 200 hi l. - Vng bin A3 : L vng bin ngoiA1, A2, nm trong vng bao ph ca cc v tinh a tnh INMARSAT, thng c gii hn t 70 v Bc n 70 v Nam. - Vng bin A4 : L vng cn li tr vng A1, A2, A3 ,v c bn l cc phn a cc. * Trang thit b i tu : - Trang thit b ti thiu (khng ph thuc vng chy tu) VHF (RT & DSC)thng tin trong vng hnh hi bnh thng NAVTEX or/and EGC receiverthu MSI (Maritime Safety Informations) Radio 2-waythng tin hin trng EPIRB thng tin cu nn khn cp SART 9GHzpht p Radar tm kim cu nn - Trang thit b ph thuc vng chy tu, mi vng bin tu cn phi trang b thm nhng thit b ph hp vi c ly thng tin : - A1 : VHF - A1 v A2 : MF - A1, A2 v A3 : Chn la thit b i tu HF or/and INMARSAT - A1, A2, A3 v A4 : Bt buc trang b thit b i tu HF * Cc h thng thng tin trong GMDSS. H thng thng tin v tinh (Satellite communications) : -INMARSAT -COSPAS-SARSAT -(GPS) H thng thng tin mt t (Terrestrial communications) : - S dng 3 di tnVHF - c ly thng tin ngn (20 nm) MF - c ly thng tin trung bnh (100 nm) HF - c ly thng tin di (nhiu nghn nm). - S dng 3 phng thc thng tin DSC- Digital Selective Calling NBDP - Narror Band Direct Printing RT- Radio Telephone II. CNG NGH DSC 2.1 KHI QUT CHUNG 1. Cc c trng ca cng ngh DSC Digital selective calling * Calling :- calling (gi) - working (lin lc) + C cc thnh phn nht nh (c nh dng Form).+ Tip theo l phng thc thng tin khc trao i thng tin (lin lc) * Seclective: a ch hoC nhiu phng thc seclective - all sations - all ships - Call group - individual : gi theo s nhn dng(ID) - geographic: selectivetheo vng a l - Mc u tin : distress urgency safecty routine. * Digital: Cng ngh thng tin s (s dng m 10 bit pht hin li v phng thc sa li FEC) tc thp, dng c knh c tn s thp v i hi t s S/N khng cao . 2. Cc cuc gi DSC thng s dng : * DSC c s dng tt c cc di tn trong thng tin mt t (DSC khng c trong thng tin v tinh) -VHF dng knh 70-MF 21875(Alert) -HF : 4,6,8,12,16 : mi di c nhiu knh cp cu v knh thng thng -DSC dng bo ng cp cu (Distress alert)-DSC dng loan bo (announce) cc cuc gi khc nh: urgency, safety -DSC dng kt ni cc thng tin thng thng (Routine) tdng 2.2TN HIU THNG DI (BAND PASS) DSC c s dng trong thng tin hng hi c ba di tn : VHF, MF, HF. di tn VHF bn cnh nhiu knh thoi, DSC ch n nh mt knh duy nht l knh70 chocmcchthngtinantoncu nn(D&S)vmc chthngtinthng thng (Public). di tn MF (2 MHz) v HF (cc bng tn 4, 6, 8, 12, 16, 18, 22, 25 MHz)- n nh cc knh u tin ring cho mc ch an ton v cu nn -cng phn chiamt sknh quct(International channel)vmtsknhkhu vc (Local channel). Cc c trng ca tn hiu thng di DSC cc di tn nh sau. 1. Di tn MF/HF. Phng thc iu ch : F1B/J2BTc iu ch : 100 bps. dch tn : 170 Hz. (J2B-sng mang ph 1700 Hz). rng di thng :300 Hz. 2. Di tn VHF. Phng thc iu ch : iu tn. Dch tn:1300 Hz v2100 HzTc iu ch : 1200 bps. Ch s iu ch : 2.0 10% . 2.3. TN HIU BNG GC (BASE BAND) 1. M 10 bit pht hin li (10-bit error detecting) * Mi t m gm 10 bit7 bit thng tin, to nn 128 t m c trng s t 0 n 1273 bit pht hin li, to nn mt s nh phn c trng s t 0 n 7, biu th s lng bt 0 trong dy 7 bt thng tin.B k hiu trng thi 0 logic tng ng vi tn s caoY k hiu trng thi 1 logic tng ng vi tn s thp. BNG 1- Bng m 10 bit pht hin li (Ten-bit error-detecting code) Trng s t m Cu trc t m v v tr cc bit 1 2 3 4 5 6 7 8 9 10 Trng s t m Cu trc t m v v tr cc bit 1 2 3 4 5 6 7 8 9 10 Trng s t m Cu trc t m v v tr cc bit 1 2 3 4 5 6 7 8 9 10 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 . 31 32 33 34 35 36 37 38 39 40 41 42 BBBBBBBYYY YBBBBBBYYB BYBBBBBYYB YYBBBBBYBY BBYBBBBYYB YBYBBBBYBY BYYBBBBYBY YYYBBBBYBB BBBYBBBYYB YBBYBBBYBY BYBYBBBYBY YYBYBBBYBB BBYYBBBYBY YBYYBBBYBB BYYYBBBYBB YYYYBBBBYY BBBBYBBYYB YYYYYBBBYB BBBBBYBYYB YBBBBYBYBY BYBBBYBYBY YYBBBYBYBB BBYBBYBYBY YBYBBYBYBB BYYBBYBYBB YYYBBYBBYY BBBYBYBYBY YBBYBYBYBB BYBYBYBYBB 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 . 74 75 76 77 78 79 80 81 82 83 84 85 YYBYBYBBYY BBYYBYBYBB YBYYBYBBYY BYYYBYBBYY YYYYBYBBYB BBBBYYBYBY YBBBYYBYBB BYBBYYBYBB YYBBYYBBYY BBYBYYBYBB YBYBYYBBYY BYYBYYBBYY YYYBYYBBYB BBBYYYBYBB YBBYYYBBYY BYBYYYBBYY YYBYYYBBYB BYBYBBYYBB YYBYBBYBYY BBYYBBYYBB YBYYBBYBYY BYYYBBYBYY YYYYBBYBYB BBBBYBYYBY YBBBYBYYBB BYBBYBYYBB YYBBYBYBYY BBYBYBYYBB YBYBYBYBYY 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 . 117 118 119 120 121 122 123 124 125 126 127 BYYBYBYBYY YYYBYBYBYB BBBYYBYYBB YBBYYBYBYY BYBYYBYBYY YYBYYBYBYB BBYYYBYBYY YBYYYBYBYB BYYYYBYBYB YYYYYBYBBY BBBBBYYYBY YBBBBYYYBB BYBBBYYYBB YYBBBYYBYY BBYBBYYYBB YBYBBYYBYY BYYBBYYBYY YBYBYYYBYB BYYBYYYBYB YYYBYYYBBY BBBYYYYBYY YBBYYYYBYB BYBYYYYBYB YYBYYYYBBY BBYYYYYBYB YBYYYYYBBY BYYYYYYBBY YYYYYYYBBB 2. M ha thng tin trong DSC . Vi 7 bit thng tin tp hp c 128 t m c trng s t 00 n127. Trong : 100 t m s c trng s 00 .. 99 : dng biu th 100 s thp phn c hai ch s t s 00 .. 99. Trng s liu trong tn hiu DSC s s dng nhiu s thp phn, nh : s nhn dng MMSI, v tr, tn s . Nh vy mi gi tr s trong tn hiu DSC s c biu th bi mt tp hp nhiu t m s. 28tmlnhctrngs100..127:biudinccmlnh.MlnhtrongDSC khng ch ph thuc tng cu trc t m m cn ph thuc v tr ca t m trong chui cuc gi DSC. BNG 2 : NGHA THNG TIN CA MT S T M LNH Trng s t m ng b hoc tn hiuduy nht (Phasing and unique functions) nh dng (Format specifier) Hng cuc gi (Category) Tnh cht tai nn (Nature of distrees) Thng tin tip theo 1 (First telecommand) 100RoutineFire, explosionF3E/G3E simplex TP 101FloodingF3E/G3E duplex TP 102Geographical area Colllision 103GroundingPolling 104Phasing RX-0 positon Listing 105Phasing RX-1 positon Sinking 111Phasing RX-7 positon H3E TP 112DistreesDistreesEPIRB emmission Distrees relay 116All shipsF1B/J2B TTY receiver 120Individual stations A1A Morse TR 127EOS 3. Phng thc FEC (Forward error correction) Mi t m c pht 2 ln, pht ln u (Dx - Direct transmission) v pht li(Rx - Re-transmission), gin cch mt khong thi gian bng thi gian pht 4 t m. di MF/HF : tc 100 bps, 4 t m gm 40 bit, thi gian gin cch l 400 ms. di VHF : tc 1200 bps, 4 t m gm 40 bit, thi gian gin cch l 33 1/3 ms. NguynlFEC:Mythusdnghailnphtcamitmsali(nuc). Khng phi tt c cc li xut hin u c th pht hin v sa c theo c ch ny, v v th DSC cn s dng cc phng php kim sot li khc (Error-check character). 2.4. CU TRC TN HIU DSC1. Cc thnh phn ca mt cuc gi DSC - Dot pattern : tn hiu mo u . - Phasing: tn hiu ng b chu trnh- Format : nh dng cuc gi- Address: a ch- Category : hng cuc gi (mc u tin). - Self- identification: nhn dng t xng- Massages : ni dung khc ca cuc gi- End of sequence (EOS) : k t kt thc cuc gi- Error-check character (ECC): k t kim tra liC th c cc loi cuc gi khng bao gm tt c cc thnh phn trn. 2. Mt s c tnh ca tn hiu bng gc : - Dot pattern : gii php h tr cho my thu trc canh a knh trn tu bin -Address :C mt s cch a ch ha trong DSC : * a ch ha theo s nhn dng MMSI (Maritime Mobile Service Identification). * a ch ha theo vng a l: - Phng thc kim sot li : - FEC : s dng m 10 bit error-detecting, pht gin cch 2 ln (FEC) - ECC : Error Check Character kim tra li c chui cuc gi .- Ni dung cc loi in khc nhau c cc thnh phn khc nhau.III. CNG NGH NBDP 3.1.KHI QUT CHUNG 1. Mt s khi nim :- NBDP- Narow Band DirectPrinting : phng thc truyn ch bng hp, thit b u cui l my in (In trc tip bng hp) Trongthngtin hng hi,DSCvNBDP ul cc phngthctruyntin bng hp, bng thng di 500 Hz, tc thp (100 bps). -PhngthcNBDPcncnhiutngikhc,nhTOR(TelexOverRadio),hay SITOR (SImplex Telex Over Radio). 2. Cc loi s nhn dng trong phng thc thng tin NBDP . * Phng thc thng tin NBDP s dng hai loi s nhn dng : SELCALL v MMSI. SELCALL - Selective call number (S gi chn) - l h thng nhn dng 4/5 ch s thp phn, trong : -cc i b c nhn dng bi mt s gm 4 ch s,-cc i tu c nhn dng bi mt s gm 5 ch s.MMSI : Maritime Mobile Service Identyfication, 9 ch s thp phn (s dng cng s nhn dng cho c phng thc DSC v phng thc NBDP). - nhm i : 0 MID XXXXX - i b : 00 MID XXXX - i tu : MID XXXXXX * S nhn dng (Identity numbers) v tn hiu nhn dng (Identity signals). S nhn dng c s dng a ch ha i telex trong cc th tc khai thc.Tnhiunhndngcsdngnhndngitelextrongccthtccng ngh . Khuyn nghITU-R M.491 quynhthutton chuyn igia s nhn dngv k t nhn dng.Tng ngvis nhn dngSELCALL(4 or 5-digitidentitynumber)ltn hiu nhn dng gm 4 ch (4-signal identity) . Tng ng vi s nhn dng MMSI (9-digit identity number) l tn hiu nhn dng gm 7 ch (7-signal identity). 3. Mt s m truyn ch trong thng tin hng hi : * M Morse l mt loi m truyn ch nhn cng, mt b m khng u . Do c tnh cht nhn cng nn thng tin Morse khng cn c s dng trong hng hi theo quy nh ca cng c Quc t v GMDSS (SOLAS74/88). * M Telex hay m ITA2: International Telegraph Alphabet No 2 - B m ITA2 c s dng trong mng Telex quc t, mt mng truyn ch tc chm (50 Bd). - S dng 5 bit m ha 32 t m (25= 32 t m) to nn mt b m y, khng c kh nng pht hin li.- c im : dung lng thp, nhng thng tin km phong ph so vi b m nhiu bit hn. * M NBDPl b m truyn ch da trn c s b m ITA2 (5 bit), nhng c kh nng pht hin li : m 7 biterror- detecting - C ch pht hin li: vi 7 bit c 128 t hp m, s dng 35 t m c t l4B/3Y - 32 trong s 35t hp m- tng ng vi m ITA2 (bng 3.2) - Cn 3 t hp m, k hiu l o, |, RQ dng iu khin ng truyn v tuynNh vy, m NBDP c 2 c im :-C c s l ITA2-C kh nng pht hin li (4B/3Y)-Cncphngthcsali,phnloiphngthclmviccaNBDP:ModeA- ARQ v Mode B FEC. * M ASCII hay m IA5 (International Alphabet 5) - Phm vi ng dng :Dch v truyn ch latin trong Email, mt dch v ca Internet. ASCII c dng lm m chun ca dch v Telex trong INMARSAT C - Cu trc m : y l mt b m y 7 bit, vi 27= 128 t m. Mt s h thng thng tin thngchnthm 1 bit kim tra chn l to nn mt t m c 8 bit = 1 byte. Vi 128 t m, c chia thnh nhm cc t m iu khin v nhm cc k t (in c), trong cc k t bao gm : 26 ch ci vit hoa (letter UPPER case) : t t hp trng s 65 .. 90 26 ch ci vit thng (letter lower case) : t t hp trng s 97 .. 122 10 ch s thp phn (Figure) : t t hp trng s 48 .. 57 Nhiu du, trong c cc du khng c trong m ITA2: @ , #, $ 3.2. TN HIU THNG DI - Trong thng tin hng hi phng thc NBDP c s dng di MF/HF :MF : hai bng tn 0,4 MHz v 2 MHz HF : 4, 6, 8, 12, 16, 18, 22, v 25MHz NBDP khng nh knh di VHF - Phng thc iu ch : F1B /J2Bi vi phng thc J2B : dch tn l 170 Hz , sng mang ph 1700 Hz. - Tc iu ch: 100 bps (thi gian pht 1 bit l 10 ms) - rng bng thng : AF = 270 340 Hz suy gim l 6 db. 3.3. MODE A - ARQ 1. Khi qut chung -ARQ -Automatic request Retransmit : T ng pht li khi c yu cu,mt phng thc kim sot li trong thng tin truyn s liu. - Phng thc NBDP Mode ARQ c s dng trong thng tin truyn ch hai chiu, gia hai i c s nhn dng duy nht . 2. Nguyn l ARQ- Trong phng thc NBDP Mode ARQ gia hai i A v B, k t c th thng tin hai chiu, hoc t i A n i B, hoc ngc li c th chuyn hng thng tin t i B n i A. Nhng v l dng thng tin Simplex, hai hng thng tin khng tn ti ng thi, mithiim,thngtin(information)chtruyntheo1chiutiphttin(ISS-InformationsSendingStation)n ithutin(IRS-InformationReceivingStation),trong khi mtknhtruyntn hiu ngclitIRSnISSvn c duytr truyntn hiu phn hi (Feed back). - Nguyn l ARQ :i pht tin ISS pht thng tin theo tng khi ba k t, ri dng li ch i thu tin IRSthukhi bakt ,kimtrapht hinli (theotl 4B/3Y)v phtmttn hiu phn hi (dng tn hiu CS Control signal). Nu i pht tin ISS thu tn hiu phn hi xc nh i thu tin IRS thu khi ba k t trc khng li th pht tip khi ba k t tip theo, nu ngc li i pht tin ISS thu tn hiu phn hi xc nh i thu tin IRS thu khi ba k t trc c li th pht li. Th tc cng ngh quy nh s ln pht li cho mi khi ba k t cc i l 32. 3. Chu trnh thi gian c s (Basic timing cycle) -ikhixngcucgi ccoili chng(Master)vikial ithng (Slave). i ch ng iu khin ng b thi gian cho qu trnh thng tin, cho d vai tr ISSvIRSc sthay igia hai ikhichuyn hngthngtin. Chunthigianca i ch ng phi c chnh xc 30 phn triu giy. - Qu trnh trao i thng tin v tn hiu phn hi gia hai i c ng b theo Chu trnh thi gian c s. - Chu trnh thi gian c s l mt khung thi gian450 ms, bao gm :thi gian pht khi ba k t thng tin ca ISS (210 ms),thi gian pht tn hiu phn hi ca IRS (70 ms), vcc khong thi gian tr ng truyn (tP) v x l tn hiu (tE) ca c hai i 4. Cc th tc cng ngh trong phng thc NBDP mode ARQ Cc th tc cng ngh trong phng thc NBDP mode ARQ c quy nh trong khuyn nghITU-RM.476-5(p dng chothit b cs nhn dng biSELCALL-4/5 ch s) v ITU-R M.625-3 (p dng cho thit b c s nhn dng bi MMSI - 9 ch s), bao gm: - Th tc bt tay (Phasing procedure), - Th tc bt tay li (Rephasing procedure), - Th tc ARQ (Traffic flow), - Th tc chuyn hng thng tin (Change over procedure), - Th tc kt thc thng tin (End off communication procedure). 3.4. MODE B FEC 1. Khi qut chung :- FEC Forward Error CorrectionMode ARQ duy tr c hai knh truyn tin : knh Forward truyn thng tin t ISS n IRS, cn knh Feedback truyn tn hiu phn hi. Trong khi mode FEC ch c mt knh thng tin Forward, khng s dng knh phn hi. - Phng thc NBDP mode FEC cn chia ra hai hnh thc thng tin :CB : Collective B-mode FEC thu chung ( khng a ch ho i thu). SB : Selective B-mode FEC la chn (a ch ha i thu). 2. Collective B-mode* Nguyn l FEC Collective : - i pht mode CB (CBSS Collective B-mode Send Station)pht chui k t lin tc khng ngt qung,mikt c pht hailn hailn(DX-DirecttransmissionvRX- Retransmission),khongthigiangincchgiahailnphtcamiktbng4ln thi gian pht mt k t tgc = 4 x 70 ms = 280ms - i thu (khng a ch ha) thu mi k t 2 ln (DX v RX), v In k t nu t nht mt ln thu khng b li (4B/3Y), hoc In du (*) nu c hai ln thu u b li (4B/3Y) * Mt s th tc (Procedure) :- th tc mo u ( phasing), - th tc sa li (Traffic), - kt thc pht (End of transmission). 3. Selective B-mode: *Nguyn l FEC Selective : - i pht mode SB (SBSS Seletive B-mode Send Station) cng nh CBSS, pht chui thngtinlintckhngngt qung,mikt cngvn c pht hailn(DXvRX) gin cch 280 ms. - Nhng so vi tn hiu pht ca CBSS, tn hiu pht ca SBSS c hai s khc bit c bn : - mt l, cc k t khng c t l 4B/3Y m chuyn thnh 4Y/3B - hai l, c a ch ha i thu bng cch gi 6 lntn hiu nhn dng ca i thu. - Cc i thu kim tra tn hiu gi, nu ng nhn dng ca mnh th thu v x l tn hiu theo c ch pht hin li o 4Y/3B, nu tn hiu gi khng ng nhn dng ca mnh th khng in bn tin c pht i t SBSS. * Mt s th tc (Procedure) :- th tc mo u ( phasing),- th tc sa li (Traffic), - kt thc pht (End of transmission). IV. KHI QUT V INMARSAT 4.1 GII THIU CHUNG -INMARSAT:InternationalMaritimesatelliteorganization-Tchcthngtinvtinh hng hi quc t (1979), sau i thnh International Mobile satellite organization (1994). - Cu trc h thng : * V tinh: GEO: H thng v tinh a hnh (GEO-Geostationary Earth Orbit).+ AOR - W + AOR - E + IOR + POR vi 2 dng ph sng: Global: ph sng rng vi Anten mt chm Conebeam Sportbeam:phsngchmnh(Sportbeam),cthtisdngtns,lmtng dung lng ca knh thng tin. 0 *Gateway:TrongHthngINMARSATccGatewaycgilLES(LandErath Station). INMARSAT B/M LES Service ProviderCountryAOR-EAOR-WIORPOR Beijing MarineChina868868 British TelecomUK002002 002 Comsat Mobile CommunicationsUSA001001001001 DeTeSat - Deutsche TelekomGermany111111111111 Eik Global CommunicationsNorway004004004004 France TelecomFrance011011011011 IndosarIndonesia007007007007 KDDJapan003003003003 Korea TelecomSouth Korea006006006006 Malaysia TelecomMalaysia060060060060 MorsviasputnikRussian Federation015015015015 OTEGreece005005005005 Polish TelecomPoland016 016Saudi Telecom Co.Saudi Arabia025 025Singapore TelecomSingapore210210210210 Station 12Netherlands012012012012 Stratos Mobile NetworksCanada013013013013 Telecom ItaliaItaly 555 555 TelstraAustralia222222222222 VSNLIndia306306306306 VishipelVietnam009 *Users:Thit b u cuithubaotrongINMARSATcgilMES(MobileEarth Staion), c dng trong nhiu lnh vc : Hng hi, Hng khng, Giao thng, 4.2 MARITIME - INMARSATCc h thng INMARSAT cung cp dch v thng tin Hng hi :INMARSAT A, B, M, mini-M, C, F CcctnhcngnghcbncacchthngINMASATcungcpdchv thng tin hng hi c th tham kho bng di y. Main Characteristics of the INMARSAT Systems H thng INMASAT-B: -INMARSAT-Brailsthaythktip,citinhonthinchohthngINMARSAT-Avcavosdngnm1993.Vnguyntccbngingnh INMARSAT-A nhng INMARSAT-B s dng k thut thng tin s nn c kch thc v trnglngnhhn,tiuthngunthn,chtlngthngtincaohn.Ngoira INMARSAT-B cn c th hot ng theo ch khu vc ca v tinh INMARSAT F3. Block diagram of basic configuration of a ship earth station (SES). -AntencaINMARSAT-BgingnhantencaINMARSAT-Anhngdotinb kthutnnnhgnhn(ngknhkhong0,9m),tnhtnghocaohnbic thm b phn truy theo v tinh. H thng INMARSAT-C: -INMARSAT-C c a vo khai thc nm 1991, y l h thng INMARSAT ti thiu nhng p ng yu cu ca cng c quc t GMDSS. H thng s dng k thutscungcpccdchvtelexvdata.ctnhcaINMARSAT-ClStoreand Forward,cthgiaotipvibtkmngdliumttnonhPSTN(Fax),ISDN, PSDN. - HthngINMARSAT-C c u imlgithnhthp, s dngantenv hng, kch thc, khi lng gn nh nn ph hp cho lp t nhng ni c kch thc vt l nh. - H thng INMARSAT-C s dng trn tu bin thng tch hp vi mt my thu gi nhm tng cng EGC ph hp vi cng c quc t v GMDSS.EGClmtdchvrtquantrngtronghthngINMARSAT-C,yldchv thng tin an ton Hng hi. INMARSAT-F: p ng nhu cu ngy cng tng trong vic truyn d liu thoi nhanh hn, cht lng tt hn, nhu cu bo mt thng tin, gim gi thnh trong vic thng tin lin lc trong lnhvcHnghi,INMARSATphttrinthmhthngthngtinvtinhmi: INMARSAT-Fleet . INMARSAT-Fleet (F) bao gm: F77, F55, F33. Thng 4-2002, F77 c a vo s dng. F77 c th ni l h thng thng tin vi cc dch v y nht trong h thng Fleet. F77 c ng knh antena khong 77cm ln nht trong h thng. F77 cho php kt ni thng tin nhanh, dung lng ln, ng truyn n nh, bao gm dch v thoi ton cu, dch v di ng ton cu ISDN , dch v gi 2chiu GMDSS ph hpvicctiu chunIMO(t chcHng hi quct),trong cng dng cuc gi u tin cho php cc cuc gi cu nn v cu h lun c kt ni trc cc cuc gi khc, dch v truyn gi d liu di ng MPDS ( tc c th ln 128 kbps) ch tnh cc theo dung lng tp tin gi i v nhn v ch khng tnh theo thi gian truy nhp. F77 vi ng knh anten ln, gi thnh cao nn thng c p dng trn cc tu vin dng, tu khch c trng ti ln. pngyucusdngINMARSAT-Ftrncctuctrngtitrungbnh-nh, yu cu thit b nh gn, d lp t, bo dng, gi thnh thp nn u nm 2003 F55 cavokhaithcvsdng.F55cngknhantennmtrongkhongt 50cm n 60cm. V F55 s dng k thut pht chm im ca h thng INMARSAT c th ln ti 64 kbps vi dch v ISDN v MPDS. TiptctheohngcitincaF55trongvicgimkchthcthitb,dlp t, bo dng v gim gi thnh a dch v INMARSAT ng dng rng ri hn trong tt c cc lnh vc Hng hi, thng 4-2003 h thngthng tin INMARSAT F33 c a vokhaithc,F33cngknhantenkhongt30cmn40cm.INMARSATF33 thngcngdngtrncctuctrngtinh,tukhch,tuc,tutuntraven bin. Tuy nhin F33 khng c ng dng mng ISDN. Cc u im ca h thng INMARSAT- F: + Dch v truyn thoi r rng, ph sng gn nh ton cu thng qua h thng v tinh ca Inmarsat. + Dch v truyn d liu 9.6 kbps cho hiu qu cao. + Dch v MPDS thun tin cho php ngi dng lun trong trng thi kt ni, gi cc r, gi cc c tnh theo dung lng tp tin gi i v nhn v ch khng tnh theo thi gian s dng. V. COSPAS- SARSAT 5.1.KHI QUT CHUNG -COSPAS:PhinmLatinhcamtcmttingNga(- -COsmicheskayaSistyemaPoiskaAvariynikh Sudov), c ngha tng t nh SARSAT. SARSAT: Search And Rescue Satellite Added Tracking - H thng v tinh tr gip tm kim v cu nn. Cc thnh phn ca h thng COSPAS- SARSAT: EPIRB - Emergency position-indicating radio beaconELT - Emergency locator transmitterPLB - Personal locator beaconLUT - Local user terminal MCC - Mission control centre RCC - Rescue coordination centre SAR - Search and rescue - COSPAS - SARSAT (di y vit tt l CS) l mt h thng thng tin v tinh lin kt quc t (SARSAT do M, Php v Canada pht trin, COSPAS do Nga pht trin) nhm mc ch pht hin tn hiu bo ng cu nn v xc nh v tr cc phng tin giao thng thy, b v hng khng b nn khi pht tn hiu bo ng cu nn khn cp.CS c s phi hp hot ng vi nhiu t chc quc t, nh : T chc Hng khng dn dng quc t (ICAO), T chc Hng hi quc t (IMO), Lin minh vin thng quc t (ITU) v nhiu t chc quc t khc . -CS l h thng thng tin v tinh, nn c cu trc c bn gm ba thnh phn nh sauKhuvtinh:baogmnhiuvtinhchohthnglinkttoncuvihaih thng v tinh : h thng v tinh tm thp LEOSAR v h thng v tinh a tnh GEOSAR. Khu trm mt t GATEWAY : trong CS gi l cc Trm s dng khu vc LUT (cng c GEOLUT v LEOLUT), cc Trung tm phi hp MCC, thu thpx l thng tin v lin kt d liu to nn mt mng thng tin ton cu. Khu USERs : l cc thit b u cui mang theo trn cc phng tin giao thng (hnghi,hngkhng)phttnhiukhncpkhibtainn,cncthgilcc BEACONs. Cc BEACONs c quan st chung bi c hai h thng v tinh LEOSAR v GEOSAR, v c cc chun tn hiu ph hp vi c 2 h thng v tinh pht hin v xc nh v tr.Trong CS ty lnh vc ng dng cc BEACONs c cc tn gi khc nhau, nh:-EPIRB (hng hi), s dng tn s pht ln l 406MHz. -ELT (hng khng), s dng tn s pht ln l 121.5 MHz-PLB (c nhn), s dng tn s pht ln l 121.5 MHz. Cn ch l tn s pht ln t BEACON 121.5 MHz s khng c s dng trong h thng CS t 01 FEB 2009, tt c cc BEACON ch s dng mt di tn s pht ln 406 MHz. H thng CS c k hoch thch ng cho s chuyn i ny. 5.2. NGUYN L HOT NG CA H THNG V TINH LEOSAR1. Cu trc h thng * Khu v tinh:HthngLEOSARgmnhiuvtinhtmthp(LEO)caCOSPAS(Nga)v SARSAT (M, Canada, Php). Qu o v tinh LEOSAR c c im : -Qu o cc,- cao khong 1000 km (COSPAS), hoc 850 km (SARSAT),-Chu k bay quanh tri t xp x 100 pht vi tc bay khong 7 km/s,-Kch thc vt v tinh khong 5000-6000 km.-Lm vic vi c hai knh ng ln 406 MHz v 121.5 MHz . S liu v v tinh LEOSAR thi im thng 10/2000 nh trong bng di y. THC TRNG V TINH LEOSAR vo thng 10/2000 COSPAS-SARSAT406 MHz406 MHz121.5 MHz243 MHz PayloadSARPSARRSARRSARR Global ModeLocal Mode Cospas-4 OONAONA Cospas-6 OONAONA Cospas-8O ONAONA Cospas-9OONAONA Sarsat-3NNOOO Sarsat-4OONO O Sarsat-6NNOOO Sarsat-7OOOO Sarsat-8UTUTUTUTUT Cc k hiu trong bng :O- ang hot ng (Operational) NA - Khng p dng (Not applicable). N- Khng hot ng (Not operational). SARP - x l tn hiu tc thi (SAR processor). SARR - lu tr v pht li (SAR repeater). UT - ang th nghim (Under test). * Khu GATEWAY :LUT-LEO ti nay (s liu cp nht ti thng 02/2008) c 46 LUT ca 28 nc, c mt s nc din tch rng c t 2 LUT tr ln. Bn vng tc dng ca LUT trong h thng LEOSAR cp nht n thng 02 nm 2008 nh trong hnh di y. Mi nc tham gia LEOSAR (c LUT) c mt MCC , cc MCC c lin kt quc tto thnh mt mng ton cu: - Xc nh trng thi v tinh. - Thng tin v cc s kin ca cc BEACONs. LEOSAR Coverage (February 2008) 1 - ALGIERS, ALGERIA 2 - OUARGLA, ALGERIA 3 - PARANA, ARGENTINA 4 - RIO GRANDE, ARGENTINA 5 - ALBANY, AUSTRALIA 6 - BUNDABERG, AUSTRALIA 7 - BRASILIA, BRAZIL 8 - MANAUS, BRAZIL9 - RECIFE, BRAZIL 10 - CHURCHILL, CANADA 11 - EDMONTON, CANADA 12 - GOOSE BAY, CANADA 13 - EASTER ISLAND, CHILE 14 - PUNTA ARENAS, CHILE 15 - SANTIAGO, CHILE 16 - BEIJING, CHINA 17 - HONG KONG, CHINA 18 - TOULOUSE, FRANCE 19 - PETELLI, GREECE20 -BANGALORE, INDIA 21 -LUCKNOW, INDIA 22 -JAKARTA, INDONESIA 23 - BARI, ITALY 24 - KEELUNG, ITDC 25 - GUNMA, JAPAN 26 -INCHEON, KOREA 27 - ABUJA, NIGERIA28 -WELLINGTON, NEW ZEALAND 29 - TROMSOE, NORWAY 30 - SPITSBERGEN, NORWAY 31 - CALLAO, PERU 32 - ARKHANGELSK, RUSSIA 33 - NAKHODKA, RUSSIA 34 - JEDDAH, SAUDI ARABIA 35 - CAPE TOWN, SOUTH AFRICA36 - SINGAPORE 37 - MASPALOMAS, SPAIN 38 - BANGKOK, THAILAND 39 - ANKARA, TURKEY 40 - COMBE MARTIN, UK 41 - ALASKA, USA 42 - CALIFORNIA, USA 43 - FLORIDA, USA44 - GUAM 45 - HAWAII, USA 46 - HAIPHONG, VIETNAM 2. Nguyn l xc nh v tr ng dng hiu ng Dopoler Khi mt v tinh LEOSAR bay qua vng c mt EPIRB c kch hot th EPIRB cthcoingyn,cnvtinhchuynng,nnkhongcchgiavtinhvEPIRB thay i, trong khi EPIRB pht tn hiu c tn s n nh , v tinh sthu c tn hiu c tn s thay i (h qu cahiu ng Doppler), cc thng tin c chuyn tip ti LUT, kt hp vi cc thng tin v v tr v tinh s xc nh c v tr EPIRB. Nguyn l xc nh v tr bng hiu ng Doppler c th din gii ngn gn nh sau: Hiu ng Doppler l mt khi nim cng ngh din t hin tng tn s tn hiu thu c thay i theo tc chuyn ng tng i gia my thu v my pht. Nu khong cch giamythuvmyphtgimnh(tcchuynnghngtmm)thtnsthu c s tng, ngc li nu khong cch gia tng (tc chuyn ng hng tm dng) th tn s thu c s gim i. V nu tc chuyn ng hng tm bng 0 th tn s tn hiu thu c bng ng tn s tn hiu pht i.Khi BEACON c kch hot, n s pht cc mu ri rc (chu k khong 50 s, rng thi gian mu khong 160 ms) tn hiu c tn s chun (460.025 MHz10 Hz). p ng ca H thng s to nn ng biu din tn s - thi gian (ri rc) ca tn hiu thu ctvtinh,imuncangcongstngngvithiimvtinhgn BEACON nht (TCA - Time of Closest Approach). dc ca ng cong ti im gn nht xc nh khong cch t BEACON ti v tinh. Bit v tr ca v tinh thi im TCA s xc nh c hai im trn mt t tha mn cc iu kin bit. Vic loi tr tnh a tr ca php o ny s thc hin c kt hp vi php o cc chu k sau, khi m vt v tinh khng lp li chu k trc v c s chuyn dch tng i qu o v tinh quanh trc tri t . 3. Cc phng thc hot ng ca h thng LEOSAR. -Phng thc bao ph khu vc, xc nh v tr tc thi (Real time)PhngthcnycsdngvivngtcdngbaoquanhmtLUTvibn knh khong 2500 km, v LUT v BEACON khi c kch hot cng nm trong vng quan st ca v tinh. Phng thc bao ph khu vc lm vic vi c 2 tn s 406 v 121.5 MHZ. - Phng thc bao ph ton cu: xc nh v tr c tr thi gian (Delay time), ch dng vi tns phtlntBEACON406MHZ.yl phngthc cho phpvtinhlutrs liu thu nhn khi bay qua vng khng c LUT, ri pht tr li khi bay qua vng c b tr LUT. Phng thc ny s khc phc thc trng cn tn ti mt s vng trn mt t m LUT. Tuy nhin tn hiu bo ng cp cu khn cp pht i t nhng vng ny ch c th xltrsaumtkhongthigiankhngqumtchukbaycavtinh(khong100 pht). 5.3.NGUYN L HOT NG CA H THNG V TINH GEOSAR 1. Cu trc h thng . * H thng v tinh GEOSAR H thng GEOSAR bao gm nhiu v tinh a tnh, thc trng c cp nht ti thng 10 nm 2008 nh trong bng di y cng bn vng ph sng ca GEOSAR. GEOSAR Satellite

GEOLUT GOES-East 075 W GOES-West 0135 W INSAT 3A 093.5 EMSG-1 09.5 E MSG-2 001 - Algiers, Algeria 2 - Ezeiza, Argentina3 - Brasilia, Brazil4 - Recife, Brazil5 - Edmonton, Canada6 - Ottawa, Canada7 - Santiago, Chile8 - Toulouse, France 9 - Pentelli, Greece 10 - Bangalore, India 11 - Bari, Italy 12 - Wellington (1), New Zealand12 - Wellington (2), New Zealand13 - Fauske, Norway14 - Maspalomas (1), Spain 14 - Maspalomas (2), Spain 15 - Ankara, Turkey16 - Combe Martin, UK 17 - Maryland (1), USA 17 - Maryland (2), USA * Nguyn l hot ng ca h thng GEOSAR -GEOSARchlmvicvitn s phtlnf= 406 MHz,khng lmvicvif=121.5 MHz - Nguyn l hot ng:Cc BEACON c cp nht v tr, hoc t my thu nh v v tinh tch hp trong thit b, hoc bng cc phng thc khc.HthngGEOSARthchinchcnngthngtinkhncp,chuyntipcctn hiu pht i t BEACON qua cc v tinh GEO, ti cc GEOLUT, s l thu nhn cc tin tc c iu ch trong tn hiu c BEACON pht i , bao hm : - S nhn dng ID (MMSI) - V tr b nn. - Mt s thng tin tm kim cu nn khc. Tuy nhintrongtn hiu pht i t BEACON,vn cburst phttn hiutns chun - khng iu ch (160 ms) lm c s cho h thng LEOSAR khoanh vng v tr b nn, duy tr s kt hp nguyn l hot ng ca hai h thng GEOSAR v LEOSAR. 5.4. TN HIU EPIRB 1. Tn hiu bng thng - Tn s sng mang 406.025 .. 406.037 MHz n nh tn s 9 2.10s- Cng sut ra 5W 2dB trn anten tr khng 50 m - Phng thc iu ch iu ch pha - Ri rc ha tn hiu di thng Chu k lp li: thay i ngu nhin trong khong t 47.5 s n 52.5 s (nhm gim s xung t tn hiu khi c nhiu BEACON cng c kch hot) Thi gian pht 440 ms (i vi loi bc in ngn 112 bits) 520 ms(i vi loi bc in di 144 bits) Trong : Phn mo u (pht tn hiu khng iu ch - CW)160 ms Phn iu ch tin tc 280 ms / 360 ms Tc iu ch 400 bps Thi gian duy tr hot ng tithiu l 24h Cng vi vic hoch nh tn s pht ln ca cc BEACON l 406.025 MHz, gp phn m rng dung lng h thng, CS cho pht trin k hoch s dng ng thi tn s th hai cho cc BEACON l 406.028 MHz . 2. Tn hiu bng gc Tn hiu bng gc trong BEACON c iu ch pha vi tc 400 bps, gm hai loi: in ngn vi di 112 bits v in di vi di 144 bits, bao gm cc thng tin v cc thnh phn tn hiu c bn sau: - Cc thng tin nhn dng BEACON - Mt s thng s tai nn, nh : v tr, tnh cht b nn (ch c trong loi in di) - Mt s thnh phn phc v mc ch ng b v kim sot li. Data Fields of the Short Message Format Data Fields of the Long Message Format 5.5. MEOSAR mt hng pht trin ca h thng CS Cc nc M, Nga v Lin minh Chu u thng nht mt k hoch chung pht trinhthngchuyntiptnhiuBEACON406MHzquaccvtinhtmtrungMEO ca cc h thng nh v v tinh (GPS, Glosnass v Galileo). HthngCSMEOSARmbokhnngcungcpdunglngngtruyn BEACON-to-Satellite tc thi ton cu, cn chc nng xc nh chnh xc v tr BEACON scthchinmtcchclpbimtmythunhvvtinhtchhptrong BEACON. H thng s c a vo hot ng vo khong nhng nm 2016-2017. VI. H THNG THNG TIN AN TON HNG HI. 6.1 KHI QUT CHUNG * MSI - Maritime safety Information - Thng tin an ton hng hi l cc thng tin d bo thi tit, kh tng, cc thng tin cnh bo hng hi v cc thng tin lin quan n an ton, khn cp hng hi khc.C th chia thng tin an ton hng hi thnh ba loi thng tin sau y :- Thng tin lin quan n tm kim cu nn trn bin (vit tt l SAR-Search And Rescue).LoithngtinnyccungcptccTrungtmphihpcunn(RCC-Rescue Co-ordinate Center, MRCC-Maritime RCC) - Cc thng tin d bo, cnh bo thi tit, kh tng, thu vn (vit tt l MET), cc thng tin ny c cung cp t cc t chc quc t cng nh cc n v thnh vin c lin quan n kh tng v thu vn (IHO, WMO). - Cc thng tin an ton hng hi khc (vit tt l NAV), nh cc thng tin lin quan n lung lch, bng tri, sa i hi , hiu chnh cc h thng dn ng, cc thng tin v cc cng trnh trin khai trn bin, tp trn trn bin, cp bin, Nhng thng tin ny c cung cp bi cc t chc quc t hoc cc n v thnh vin lin quan n bo m an ton hng hi.*TrongHthngGMDSS, MSIc phtrng khp(World-WideNavigational Warning Service-WWNWS) bi 3 h thng: - H thng NAVTEX quc t : pht MSI bi h thng cc i pht sng trung - H thng SafetyNET: pht MSI qua INMARSAT C - H thng HF NBDP mode FEC : pht MSI cho vng bin xa khng ph sng bi INMARSAT * Yu cu trang b my thu thng tin an ton hng hi MSI l yu cu bt buc i vi mt i tu trong h thng GMDSS, vi s kt hp linh hot cc loi thit b sau : - My thu NAVTEX (518 kHz hoc 518 kHz + 490 kHz). - My thu dch v EGC (mt dch v tch hp trong h thng INMARSAT C) - My thu ton di sng HF c thu c phng thc NBDP mode FEC. 6.2 H THNG NAVTEX QUC T. NAVTEX l mt h thng pht qung b thng tin MSI v c thu t ng bi vic ng dng cng ngh NBDP mode FEC. H thng NAVTEX quc t l h thng NAVTEX s dng tn s 518 kHz vi ngn ng ting Anh v c s phi hp quc t. H thng NAVTEX khu vc l h thng NAVTEX s dng cc tn s khc vi 518 kHz(490kHz hoc 4209.5kHz)v cth s dng ngn ngkhctingAnh clatin ha. 1. Phn knh trong h thng NAVTEX quc t: H thng i pht NAVTEX quc t v ch s dng duy nht mt tn s 518 kHz, vi vng ph sng ca mt i pht (thng c cng sut pht 1- 5 kW) khong 400 Nm, nn cn c quy hoch phn knh cho cc i pht NAVTEX quc t trnh can nhiu ln nhau.IMOquynh3phngthcphnknhchohthngNAVTEXquct:phn knh theo vng a l, phn knh theo thi gian, v phn knhtheo quy hoch quc t. a)Phn knh theo vng a l. IMO phn chia vng chy tu trn ton th gii thnh 16 vng a l vi kch thc lnsovivngphsngcamiiphtNAVTEX,gilccNAVAREA.Nu trong cng mt khong thi gian mi vng NAVAREA ch c mt i pht NAVTEX (vi s phn b v tr hp l) hot ng, th d s dng chung tn s pht 518 kHz nhng vi khong cch xa (c th ti hng nghn Nm) cc i pht NAVTEX cng khng gy can nhiu ln nhau. Bn quy hoch 16 vng NAVAREA c v di y. b)Phn knh theo thi gian. Trong mi NAVAREA, cc i pht NAVTEX li c phn knh theo thi gian. IMOchiakhongthigian pht cho hthngNAVTEX quctthnh nhiukhe thi gian, mi khe thi gian c rng 10 pht, bt u t pht chn chc (theo gi quc t UTC). Trong ngy mi i pht NAVTEXc quy nh pht nhiu ln vi chu k lp li l 04 gi. Do c th b tr 24 khe thi gian khng trng nhau quy hoch cho 24 i phtNAVTEXchomivng al,vi m nhn dng bi 24 ch cilatintAnX, nh trong bng di y. c)Phn knh theo quy hoch quc t. IMO c quy hoch h thng i pht NAVTEX phn b tng i ng u trong mivngNAVAREAvccchquynhcciphtNAVTEXcngmnhndng (pht cngthigian)ccvngNAVAREAkhcnhau ckhong cch alxanhau. Hng phn b v tr cc i pht theo m nhn dng t A n Z (tc l v tr khe thi gian tng dn) c IMO quy nh nh trn bn cc vng NAVAREA. 2. nh dng mt bc in NAVTEX Trong nh dng in NAVTEX, tn hiu mo u (Phasing signals) v tn hiu kt thc (End of emissions) theo ng th tc cng ngh NBDP mode FEC. Phn k t c pht bao gm cc thnh phn sau : ZCZC l cm k t m u mt bc in NAVTEX NNNN l cm k t kt thc bc in 1 2 3 4B B B Bl cm tn hiu nhn dng bc in, trong B1 l tn hiu nhn dng i pht NAVTEX B2 l tn hiu nhn dng ch ni dung in 3 4B B l s bc in gm hai ch s thp phn 3 4B B = 00 : s bc in c bit, loi in khn cp 3 4B B= 01 .. 99 : s bc in cc loi in khc C th trong khong thi gian 10 pht cho php, mt i pht c th pht hai hoc nhiu hn s bc in NAVTEX.6.3 H THNG SAFETY NET. 1. Khi qut chung. SafetyNET l mt dch v pht bo thng tin an ton hng hi MSI trong h thng GMDSS qua v tinh INMARSAT, c vng ph sng rt rng. Vcngngh,SafetyNETlmttronghaidchvccungcpbihthng EGC (Enhanced Group Calling system), mt tiu h thng c tch hp trong H thng INMARSAT C. 2. H thng EGC . TrongcutrcknhthngtincaHthngINMARSATC,ccbcinEGC c pht trn knh TDM ca NCS. H thng EGC cung cp hai dch v : - Dch v SafetyNET : c dng pht qung b thng tin an ton hng hi MSI, v - Dch v FleetNet : c dng pht thng tin cng cng, hay thng tin qun l khai thc i tu (non GMDSS).Cc bc in (Shore-to-Ship) ca EGC c th c a ch ha hoc theo vng a l (area calls) hoc a ch ha theo nhm i tu (group calls) : -Cccucgitheovngalcthachhatheovngalnnh(16 NAVAREAs),hocachhatheovngalnhtnh(temporarygeographical area)dng hnh trn (vi thng s l ta tm im v bn knh) hay dng hnh ch nht (vi thng s l ta im cc Ty Nam v kch thc hai cnh). Cc cuc gi theo vng a l c i tu thu nhn t ng thng qua la chn mt hoc mt s vng a l cn thu thng tin, hoc thng qua xc nh v tr cp nht ca i tu lin quan n vng a l nht nh. - Cc cuc gi theo nhm cng c i tu thu t ng thng qua thng s nhn dng nhm lin quan n tng loi in. in EGC l mt loi thng tin mt chiu (Shore-to-Ship) ng dng phng thc sali FEC (forward error-correction techniques), tc thp (1200 bps), vi m truyn ch ASCII. 3. H thng SafetyNET. SafetyNET l mt h thng cu thnh ca H thng GMDSS, s dng dch v EGC pht qung b thng tin an ton hng hi MSI. cquyhochquctvcchphihpthngtinvlchtrnhphtcah thng SafetyNET. 6.5.H THNG HF NBDP. pht thng bo an ton hng hi MSI cho cc vng bin khng c kh nng ph sngbicchthngNAVTEXquctvSafetyNET,HthngGMDSScnch thng HF NBDP mode FEC. Cc tn s quc t c quy nh pht MSI di tn HF l :Di 4 MHz 4210 kHz6 MHz 6314 kHz8 MHz8416.5 kHz12 MHz 12579 kHz 16 MHz 16806.5 kHz19 MHz 19680.5 kHz22 MHz 22376 kHz26 MHz 26100.5 kHz Nhiu quc gia c k hoch pht trin h thng HF NBDP MSI . Chng 2 QUY HOCH H THNG GMDSS (GMDSS Update) 1. CC VNG THNG TIN BIN 1.1. Khi nim v cc vng thng tin bin trong h thng GMDSSGMDSS m bo thng tin hng hi ton cu vi s phn chia thnh 4 vng hot ng ca tu bin nh sau:- Vng bin A1 l vng bin c ph sng bi t nht mt i b VHF - thoi, c trc canh bo ng lin tc bng phng thc DSC.-Vng bin A2 l vng bin nm ngoi A1, c ph sng bi t nht mt di b MF - thoi, c trc canh bo ng lin tc bng phng thc DSC.- Vng bin A3 l vng bin nm ngoi cc vng A1 v A2, c ph sng bi cc v tinh a tnh trong h thng INMARSAT. Vng ph sng ca cc v tinh thng tin a tnh trong khong t 70 v bc n 70 v nam.- Vng bin A4 l vng bin nm ngoi cc vng A1, A2 v A3. l vng bin gn hai cc tri t.Vng bin A3 c cung cp cc dch v ca H thng INMARSAT mang tnh quc t cao vi vng ph sng rng. Vng bin A3 v A4 cn c cung cp cc dch v thng tin bi cc i HF c c ly thng tin xa (nhiu nghn hi l). Cc nc c b bin thng quan tm pht trin vng bin A1, A2 , c bit nhng nc vng v tuyn cao, iu kin thng tin v tinh a tnh b hn ch. 1.2. Phng php xc nh c ly vng bin A1 v A2.NghquytA.801(19)caIMOngy23/11/1995vCungcpccdchvvinthng trong GMDSS ra cc tiu chun thit lp cc vng bin trong GMDSS, trong c cc tiu chun thit lp cc vng bin A1, A2 [1]. Tiu chun thit lp vng bin A1 ch yu ph thuc cao anten i b VHF. Ngh quyt A.801 a ra khuyn ngh xc nh bn knh ph vng bin A1 theo cng thc : A[Nm] = 2.5*( H(m) ( )) h m +(1) trong : H l cao ca anten i b VHF tnh bng met, h l cao ca anten i tu VHF tnh bng met. Vi gi tr gi nh ca h = 4 m, c ly A vi cc gi tr in hnh ca H, nh sau : Bng 1 : Cc gi tr in hnh ca c ly vng bin A1 H h 50 m100 m 4 m23 Nm30 Nm Tiu chun thit lp vng bin A2, , c ly thng tin vng bin A2 c tnh ton vi iu kin truyn lan sng t trn mt bin, theo Khuyn ngh ITU - R P.368 - 7 (Ground - Wave Propagation Curves for Frequency between 10 kHz and 30 MHz) v ITU-R Report 322 (Radio Noise).V l thuyt, vng bin A2 l vng bin nm trong mt vng trn bn knh B (Nm) c tm l v tr t anten thu ca i b MF v ngoi vng bin A1. Bn knh B c th xc nh cho mi i b vi cc iu kin sau:+ Phng thc thng tin: thoi n bin(J3E) + Cng sut pht i tu: 60W + Hiu sut anten i tu: 25% + Phng thc truyn sng: sng t + Tn s: 2182 kHz + Di thng: 3kHz + d tr pha inh: 3dB. + T s S/N (RF): 9dB (voice)C ly thng tin vng bin A2 phi c thm nh thc t bng vic o cng trng.Phng php tnh c ly thng tin vng bin A2 c a ra trong ti liu [3], trn c s hng dn ca IMO trong ngh quyt A.801 v cc khuyn ngh ITU-R P.368-7 v ITU-R Report 322. Cc kt qu tnh ton cho mt s v tr a l in hnh ca b bin Vit nam nh trong bng 2 Bng 2 : C ly vng bin A2 tnh ton cho mt s i b MF [3] i MF V Bc Kinh ng Gi tr B (km) Gi tr B(hi l) Hi Phng20055.55106041.19250135 Bn Thy18030.57105042.21223120 Nng16003.32108012.32199107 Quy Nhn13047.00109014.00183 99 Nha Trang12016.00109010.00180 97 Vng Tu10020.72107005.67188101 C Mau09012.01105010.48197106 2. QUY HOCH TNG TH GMDSS 2.1. Thng t GMDSS.1/Circ.X ca IMO Thng t GMDSS.1/Circ.13 ngy 23/05/2011 l ti liu cp nht mi nht ca IMO [2] v Quy hoch tng th GMDSS (GMDSS Master Plan). Vi c trm trang s liu, Thng t GMDSS.1/Circ.13 cung cp thng tin v thc trng trang thit b i b trong GMDSS, vi nhng ni dung chnh nh sau : - Tng quan v trang thit b thng tin hng hi cc nc, bao gm c thng tin v tinh, thng tin mt t v thng tin an ton hng hi. - Danh b i b trc canh DSC, bao gm cc thng s : Tn i, loi i, s nhn dng, v tr, c ly thng tin , cc loi i VHF (A1), MF (A2), HF (A3, A4). - Danh b cc i pht thng tin an ton hng hi : NAVTEX, HF NBDP- Danh b cc i LES trong h thng INMARSAT - Danh b cc i LUT, MCC trong h thng COSPAS-SARSAT. 2.2. Nhn xt v quy hoch tng th GMDSS - Nhm cc nc pht trin c quy hoch h thng thng tin hng hi y cc dch v c cung cp t cc h thng thng tin mt t v thng tin v tinh. -Nhm cc nc cnchm phttrinthngtin hng hi cnthiu nhiu dchvvvn cn ang c k hoch pht trin hon thin, c th k trong c Vit nam. c bit P. R. KoreavCubagnnhchaphttrinhthngthngtinhnghitheocngc GMDSS. Bng 3 : Quy hoch h thng thng tin hng hi ca mt s nc in hnh 3. QUY HOCH VNG BIN A1, A2 TRONG GMDSS 3.1. c im chungNhiu nc quan tm pht trin vng bin A1 (ph sng bi h thng cc i b VHF) v vng bin A2 (ph sng bi h thng cc i b MF di 2MHz). c bit l cc nc Bc u, c vng bin v tuyn cao, thng tin v tinh a tnh khng hon ton c u th. C nhng nc vng bin v tuyn thp khng t ra k hoch pht trin h thng i b VHF ph kn vng bin A1, nh Nht bn, Australia, mc d cc h thng thng tin hng hi khc pht trin kh hon thin. COAST STATION COSPAS-SARSAT DSCLES INMARSATSafety NETSTTCountry A1A2A3A4BCF SES for RCC NAVTEX NAV MET SAR HF NBDP MCCLUT 1ChinaOOPOOOOOOOO 2FranceO&POOOOOOOOO OO 3GreeceOOOOOOOOOO OO 4Hong KongOOOOOOOO OO 5IndiaOO&PO&POOOO&POOO OO 6JapanOOOOOOOOO OO 7KoreaOOOOOOOOO 8NorwayOOOOOOOTTOT OO 9RussianOO&POO&P O&POOO OO 10SingaporeOOOOOOO OO 11United KingdomOOOOOOOOOO OO 12United StatesPO&POOOOOO&POOOOOO 13VietnamO&POOOOPOOO 14TurkeyOOOOO OOO 15IndonesiaO&PO&PO&POOPOO 16EgyptOOOOO P 17P. R. KoreaO 18Cuba 3.2. Quy hoch vng bin A1, A2 ca Nauy Nauy l mt trong nhng nc pht trin hon thin nht vng bin A1 v A2. Nauy l nc Bc u, c vng bin v tuyn cao, c b bin cng khong hn 3000 km nh Vit nam, nhng H thng cc i b VHF v MF ca Nauy rt pht trin c v s lng v cch t chc h thng i. H thng i b VHF ca Nauy gm 05 i chnh (Main Staion) iu khin hn 100 i iu khin t xa (Monitor Station). Cc i VHF ca Nauy c c ly ph sng t 17 Nm (Ligtov) n 93 Nm (Sogndal, Storehogen). Lu l c ly ph sng ca i VHF ph thuc cao anten i b VHF theo cng thc (1), chng t c i VHF ca Nauy t trn ni cao, c v tr ti gn 1000m. Cc i chnh VHF ca Nauy gm :Tjme Radio (002570100) iu khin 09 i Monitor;RogalandRadio (002570300)iu khin 18 i Monitor ;Flor Radio (002570500) iu khin 32 i Monitor (bng 4) ;Bod Radio (002570700) iu khin 28 i Monitor vVard Radio (002570800) iu khin 16 i Monitor. H thng cc i MF ph sng vng bin A2 ca Nauy bao gm 05 i Main station cng c MMSI : 002570100, .. , 002570800 v 11 i Monitor station, tng cng 16 i MF, u cng b c ly ph sng 200 Nm. Bng 4 : H thng cci VHF Monitor c iu khin bi i Flor Radio(002570500) STTTn iV tr Tm xa (Nm) 1Oseberg6029'.54N 00249'.63E30 2Gulen6102'.04N 00509'.18E73 3Ligtvor6106'.05N 00632'.08E17 4Sogndal, Storehogen6110'.23N 00707'.09E93 .... 30Rrvik, Falkhetta6452'.45N 01113'.32E43 31sgard B, The North Sea6506'.61N 00647'.36E30 32Heidrun, The North Sea6519'.45N 00718'.96E30 3.3. Quy hoch vng bin A1, A2 ca Vit nam H thng i b VHF ca Vit nam u l i Main Station, mi i c mt s nhn dng, ngoi 18 i hot ng nh trong bng 5, Vit nam cn c k hoch pht trin (planned) 11 i b VHF khc. Cc i c ID dng 005741xxx kt ni vi MRCC Hi phng, cc i c ID dng 005742xxx kt ni vi MRCC nng, cn cc i c ID dng 005743xxx kt ni vi MRCC Vng tu. Tt c cc i b VHF ca Vit nam u cng b vng ph sng 30 Nm. So vi Nauy, mt nc c chiu di b bin tng ng, thit lp vng bin A1 vi hn 100 i VHF, vi nhiu i vng ph sng 50-90 Nm, th h thng i VHF ca Vit nam cha m bo ph kn vng A1 ven bin Vit nam. Bng 5 : H thng cc i b VHF ca Vit nam TTTn i MMSI (MainStation) V tr C ly (Nm) 1Mng Ci0057410102131'.38N 10758'.19E30 2Ca ng0057410202101'.12N 10724'.01E30 3Hn Gai0057410302057'.15N 10704'.22E30 4Hi Phng0057410402047'.50N 10642'.54E30 5Thanh Ho0057410601917'.99N 10549'.16E30 6Bn Thu0057410701830'.57N 10542'.21E30 7Hu0057420201632'.38N 10738'.24E30 8 Nng0057420301607'.56N 10815'.06E30 9Quy Nhn0057420601347'.00N 10914'.00E30 10Ph Yn0057420701253'.40N 10927'.12E30 11Nha Trang0057420801229'.27N 10915'.50E30 12Phan Giang0057421001133'.53N 10900'.23E30 13Phan Thit0057430101054'.55N 10806'.11E30 14Vng Tu0057430201021'.59N 10704'.01E30 15H Ch Minh0057430301021'.28N 10704'.15E30 16Cn Th0057430501002'.00N 10547'.00E30 17C Mau0057430700912'.01N 10510'.48E30 18Kin Giang0057430800922'.00N 10426'.00E30 H thng i b MF ca Vit nam gm 13 i (bng 6) u cng b vng ph sng 200 Nm, phn b khng tht hp l, vng bin pha Bc Vnh Bc b c ph sng bi nhiu i gn nhau (Mng Ci, Ca ng, Hn Gai, Hi Phng) v vng bin Nam Vnh Bc b cng ph sng bi nhiu i gn nhau (H Ch Minh, Vng tu, C Mau). Bng 6 : H thng cc i b MF ca Vit nam TTTn i MMSI (MainStation) V tr C ly (Nm) 1Mng Ci 0057410102131'.38N 10758'.19E200 2Ca ng0057410202101'.12N 10724'.01E200 3Hn Gai0057410302057'.15N 10704'.22E200 4Hi Phng0057410402050'.55N 10641'.19E200 5Bn Thu0057410701830'.57N 10542'.21E200 6Ph Yn0057420131253'.40N 10927'.12E200 7Hu0057420201632'.38N 10738'.24E200 8 Nng0057420301603'.32N 10812'.32E200 9Nha Trang0057420801216'.00N 10910'.00E200 10 Vng Tu0057430051020'.72N 10705'.67E200 11 H Ch Minh0057430301023'.32N 10708'.57E200 TTTn i MMSI (MainStation) V tr C ly (Nm) 12 C Mau0057430700912'.01N 10510'.48E200 13 Kin Giang0057430800922'.00N 10426'.00E200 4. KT LUN K hoch pht trin cc vng bin A1, A2 c cc nc c bin ch trng xy dng trong mt quy hoch tng th h thng GMDSS. Quy hoch vng bin A1, A2 ca Nauy l mt mt quy hoch in hnh m bo ph sng tin cy kn vng ven bin ca Nauy. Trong khi h thng cc i b MF ca Vit nam c phn b cha tht hp l, cn h thng cc i b VHF cn cn pht trin hon thin hn, nu Vit nam c mc tiu ph kn vng bin A1. TI LIU THAM KHO [1] IMO, Handbook on the Global Maritime Distress and Safety System, London 3rd Edition, 2001 [2] GMDSS.1/Circ.13, Master Plan of Shore-based facilities for Global Maritime Distress and Safety system (GMDSS), London, 23 May 2011. [3] Trn Xun Vit, Phng php xc nh gii hn vng bin A2 trong h thng thng tin an ton v cu nn hng hi ton cu (GMDSS), K yu Hi ngh Thng tin v nh v v s pht trin kinh t bin Vit nam, H Ni 15-16/12/2007, tr.96-100. Mng C iCa ngLUT HPThChuQun oHong SaB ch Long VHn GaiHiPhngBn ThuHn L aCa V i tHu NngDung QutQung Ng iQuy NhnPh Y nNha TrangCam RanhPhan RangPhan Thi tV ng TuCn oCn ThB c Li uC MauPh QucH Ti nHCMLES HPThanh HoK i n Gi angQun oTrng Sa ithng ti n vti nhmt t I NM ARSAT iL UT/M CC Vi tNam ithng ti n duy nhiV ng ph sng iVHFV ng ph sng iMFTrung tm x l t hng ti n H Ni Bn quy hoch cc i thng tin hng hi ca Vit nam. Chng 3 H THNG INMARSAT FBB (GMDSS Extend) 1.Cu hnh H thng V tinh INMARSAT-4 INMARSAT th h 4 (I-4) cung cp cc dch v thng tin di ng bng rng ton cu vi 3 v tinh GEO cng ngh Spot-beam, cc kinh : EMEA - 25E,Asia-Pacific - 143.5E vAmerica 98W, nh trn hnh 1 2.Cu hnh H thng mt t INMARSAT-4 -Satellite Access Stations (SAS) Ba trm truy nhp v tinh (Burum- Netherlands, Fucino-Italia v Hawaii-USA, mi trm c hai RAN-Radio Access Network) cung cp lin kt truyn thng cng l giao din vtuyngiatngvtinhINMARSAT-4vimngtruynthngmtt.MiSAS,s huv qunl biINMARSAT,cmttrmanten giaotipv tuynvivtinhv cc kt ni trc tip vi cc mng PSTN, ISND v Internet. -Regional Hubs or Points of Presence (PoPs) Cctrmghpnikhuvc(theRegionalHubs)lcctrmcngcaI-4trong mngsliugitoncu.BaHubkhuvclTELXtiNewYork,TELECITYti Amsterdam v HKCOLO ti Hng Kng. -Network Operations Centre (NOC) Trungtmiuhnhmng(NCC)ctTrscaINMARSATtiLun n, cung cp ti nguyn v qun l mng ton cu INMARSAT-4. -Satellite Control Centre (SCC) Trungtmiukhinvtinh(SCC)cngcttitrscaINMARSAT Lun n lm chc nng gim st v bo tr cc qu o v tinh. -Business Support Services (BSS) Bphnkinhdoanh(BSS)ccdchvINMARSAT-4cngttitrs INMARSAT Lun n, v cung cp ton b cc dch v h tr kinh doanh bao gm cc d liu thanh ton, qun l v chm sc khch hng. 3.Dch v ca H thng I-4 - a lnh vc : Hng hi (Maritime) Hng khng (Aviation) Mt t (Land) Land Maritime Aviation I-4 (BroadBand) BGANBroadband Global Area Network Simultaneousvoice and broadband data. FleetBroadband (FBB) Simultaneousvoice and broadband data. SwiftBroadband Simultaneousvoice and broadband data. I-3 (Spot-Beam) BGAN M2M IsatData Pro IsatM2M Machine-to-machine services. Fleet 77, 55 and 33 Voice,faxanddata communications. Swift 64 Voice and 64kbps data. I-2 (Global) IsatPhone Link IsatPhone Pro Voice services. FleetPhone Maritimesatellite phone. Classic services Voice,low-speeddata andsafety communications. Safety Distress communications. Crew calling Low-costship-to-shore communications. -FBB - Fleed BroadBand Voice 4kbps circuit-switched serviceVoicemailEnhancedservices:callwaiting,forwarding,barring, holdingBroadcast quality voiceDataStandard IPHigh Speed Standard IP (NOT MPDS)Variable bit rate service Shared & Best EffortUp to 432/432 kbps (send /receive)DataStreaming IPOn-demand guaranteed bit rate service32, 64, 128, 256 kbps (send & receive)(ISDN legacy compatibility)Global Text Send and receive text messages via your laptop FBB htr hai c chtruynthng dliu:chuynmchknhv chuynmch gi(IP).VtrongcchchuynmchgiIPchaihnhthcdchvIPtiuchun (StandardIP)vIPnnh(StreamingIPmbochtlngdchv).Thnghal FBB cung cp ba loi kt ni d liu ph hp vi nhu cu lu lng v hiu qu chi ph. OneDevice,TwoDomains,ThreeDataNetworks(1thitb,2cchchuyn mch, 3 mng d liu) One Device : mt thit b u cui i tu Two Domains : hai c ch chuyn mch chuyn mch knh v chuyn mch giThree Data Networks : ba mng d liu mng chuyn mch knh, mng IP chia s (standard) v mng IP n nh (streaming) Standard IP (Dch v d liu chia s) l dch v truy nhp d liu IP ln ti 432 kbps nhiuthu bao chia scngmt c sti nguyn hthng(tyloithit b u cuiv tnhtrngthu baocng chiasti nguyn hthng).StandardIPph hpvi cc ng dng vn phng, nh duyt Internet, e-mail, FTP v nhiu ng dng hng hi nh hi int, cp nhtthngtinthitit,gimst bungmyylloi dchv cs dng trong hu ht cc ng dng ca i tu. Streaming IP (dch v d liu knh n nh) cung cp cho khch hng dch v d liu m bo bng thng (khng b tranh chp kt ni). Mt hoc mt s kt ni Streaming IP chuyn dng c th cng c h tr. Streaming IP lun sn sng cung cp dch v theo nguyn tc first-come first-served. Streaming IP l yu cu rt quan trong trong cc ng dng thi gian thc nh hi ngh truyn hnh. FBB cung cp cc cp d liu Streaming IP cc tc t 32, 64, 128 hoc 256 kbps. Dch v d liu chuyn mch knh c FBB cung cp c hai loi d liu ISDN 64 kbps v cc dch v trn c s knh 3.1 kHz audio. Cc dch v d liu chuyn mch knh c th c cung cp ng thi vi dch v d liu chuyn mch gi Standard IP, nhng khngthcungcpngthividchvdliuchuynmchgiStreamingIP.Kh nng cung cp dch v d liu chuyn mch gi cn ph thuc vo loi thit b u cui FBB. Loi FBBISDN3.1 kHz audio FBB 500 vv FBB 250 xv FBB 150 xx Dch v thoi quay s s dng cng ngh m ha ting ni AMBE+2 . FBB cho php s dng ng thi dch v thoi chuyn mch knh cng vi cc dch v Standar IP hoc Streaming IP. Cc tnh nng ca dch v in thoi quay s ca FBB gm : -Cung cp trn tt c cc loi thit b u cui FBB -Cng cp cht lng vi cc mng thoi Land line khc -Gi i v n : i.Mng PSTN ii.Mng di ng iii.Cc u cui FBB khc -C th s dng ng thi vi cc loi dch v d liu khc -Cungcp cc dchvgitrgiatngkhc nh ccmnginthoikhc, nh : th thoi, ch cuc gi, chn cuc gi .. SMS:FBB cngtch hp dchv nhn tinSMS vi y cc tnh nng. Cc nh dng tinnhnSMS theo tiuchun160ktnhngkhngh tr ni tinnhnSMS.C th giv nhntinnhnSMS nvit thitbucui FBBkhc v cthsdng thng qua my tnh xch tay hoc mytnhcabn bngcchs dng tin ch FleetBroadband LaunchPad . 4.Thit b u cui thu bao (Terminal). Chailoi thitbucui cxcnh v loi cphduyt cho cc dch v FleetBroadband. H cgi l Class8 (HighGain Antenna "FB500") v lp 9 (Gain Antenna thp FB250 "v" FB 150") thitbucui. Skhcbit chnh gialp 8 v lp 9 l ng ten. C hai loi thit b u cui thu bao FBB theo phn loi v tng ch anten, l Class 8 (High Gain Antenna FB500) v Class 9 (Low Gain Antenna FB250 v FB150). S khc bit c bn l tng ch anten. S phn loi cc thit b u cui da vo cc tiu ch : -Giao din v tuyn vi tng ch anten la chn. -Cc tnh nng v loi dch v vi tng cp thit b. -Cc tiu chun thit b u cui khc Bng phn loi cc tnh nng c bn ca cc loi thit b u cui FBB, nh sau : 5.Kt lun : Trn c s pht trin qua nhiu th h INMARSAT vi di tn dnh cho thit b u cuithubaoL-band,FBBthhinnhiuctnhquantrng: - Mng dch v ton cu -Bng thng rng (Broad Band) -Dch v thoi tin tin (AMBE+2) -S dng ng thi dch v thoi v d liu -Anten gn, nh-La chn dch v linh hot ph hp vi yu cu v kinh ph. Trong nguynl hthng caINMARSAT-4vmt smngtruyn thngton cu xuthinthutngcngnghmi:DPPOPDistributionPartnerPoint-of-Presence: mt khi nim Cng ngh thng tin gn nh ISP (Internet Service Provider).