Trng i Hc Bch Khoa H NiKhoa in T Vin Thng()

BO CO MN HC K THUT NH V V DN NG IN T ti : M PHNG MN HNH HIN TH RADAR

Gio vin hng dn

: TS. H Duyn Trung :

Sinh vin thc hin

V Vn Sn - T9 ng nh Nht T9 ng Quc Cng T11 H Ni 5/2011

LI M URadar l tn vit tt ca Radio Dectection and Ranging c ngha l phng tin dng sng v tuyn in pht hin v xc nh v tr mc tiu. Tn ny do Hi qun M t ra trong i chin th hai, tuy cha ngha nhng cng tr nn thng dng trn th gii. Trong cc loi v kh, kh ti cng ngh cao th Radar l mt trong cc kh ti c nhiu ng dng c bit. Radar c kh nng pht hin ra mc tiu c ly rt xa trong bt k iu kin no, tnh ton c tc , hng bay v cc c im ca mc tiu ch th cho cc n v ha lc c th bm st v tiu dit mc tiu. Sau chin tranh, k thut tn la v v kh tin cng hng khng ngy cng pht trin th vai tr ca Radar ngy cng tr nn quan trng. Radar phng khng l lc lng m bo ch yu tin tc v my bay ch trong i hnh chin u ca qun chng phng khng c mt trn khp cc chin trng, phc v cc chin dch, cng lc lng phng khng nh thng cuc chin tranh bng khng qun ca quc M. Trong cuc chin tranh vng Vnh, bng v kh cng ngh cao vi th on tc chin din t, M v lin qun v hiu ha h thng Radar phng khng ca Irc t lm ri lon h thng ch huy, lm mt hiu lc h thng phng khng ca Irc khin cho Irc phi chu tht bi mc d Irc c trong tay mt lc lng qun s khng l. p dng vo mc ch ha bnh ca Radar li cng t r tnh u vit ca n, Nh Radar m vic diu khin cc con tu v tr tht d dng v chnh xc. Khng nhng th, trong lnh vc kh tng thy vn, Radar gip cho vic d bo thi tit c chnh xc v thun li hn rt nhiu. Radar c th pht hin c s bt thng ca kh quyn xa hng trm Km, gip my bay, tu b c th phng trnh c thin tai. Nh c Radar m my bay c th h cnh v ct cnh trong bt k trng hp thi tit no; Cc tu

bin i li c an ton, trnh c s va chm vi cc tu b khc, trnh khi m vo cc tng bng tri. Hin nay Radar c ng dng trong rt nhiu ngnh k thut v i sng. Do vy vic nghin cu, pht trin Radar c cc nc trn th gii c bit quan tm v ch trng. Trong phn ny, chng em m phng mn hnh hin th ca mt h thng Radar v cc phng php hin th mc tiu. Do hn ch v mt kin thc v thi gian nn chng trnh cn nhiu thiu st, chng em mong thy v cc bn ng gp kin bi tp ngy cng hon thin.

I.

GII THIU CHUNG 1. Nhng vn chung v Radar Radar l thit b m bo nhn nhng tin tc v nhng mc tiu nh

thu v phn tch sng v tuyn. Mc tiu c th l: Loi kh ng lc: my bay, tn la c cnh Loi vt i chu v v tr: u n ht nhn, v tinh Mc tiu trn mt t, trn mt nc v mc tiu c ngun gc thin nhin. Qu trnh nhn bit tin tc Radar trong nhiu trng hp c th chia thnh cc bc sau: Pht hin mc tiu: l quyt on c hay khng c mc tiu trong mt vng khng gian vi xc sut quyt on sai no cho php. o ta v cc tham s chuyn ng vi mt sai s cho php no . Phn bit mc tiu l bi ton pht hin v o c cc tham s ca mc tiu khi gn mc tiu ny cn c nhng mc tiu khc. Nhn bit mc tiu: i Radar s xc nh mc tiu thuc loi no, ca ai, bay i u, trn ng bay no do trn mc tiu phi gn transponder. Bc ny ch c Radar th cp. Cc thit b Radar phi c kh nng chng nhiu cao i vi nhiu thin nhin v nhiu nhn to. Kh nng chng nhiu l kh nng ca i Radar m bo c cc ch tiu cht lng, pht hin, o lng mt mc cho khi c nhiu, cng chnh l kh nng s dng ngun nhiu lm tin tc Radar. Sng Radar c th l sng siu m dng pht hin mc tiu di nc. Thng thng sng Radar l sng in t c bc sng t 1mm n 100km. Cc sng di mm, cm, m c vai tr quan trng nht.Hin nay cc sng in t ngn hn: sng hng ngoi, sng nh sang cng c s dng trong Radar.

2. Nguyn tc nhn tin tc Radar Nhng tin tc v mc tiu mang trong tn hiu Radar l nhng dao ng in t c cc tham s lin h cht ch vi cc tham s ca mc tiu. Phng php nhn tin tc Radar thng thng nht l phng php Radar ch ng. Radar ny chiu x mc tiu nh nng lng in t v sng phn x bi mc tiu bng thit b thu. Phn x sng xy ra gii hn hai mi trng c cc tnh cht in t v t khc nhau. Ch nhng dao ng in t chiu x mc tiu vn cha phi l tn hiu Radar v chng khng cha ng nhng tin tc v mc tiu Khi cn nhn bit mc tiu, tn hiu Radar c to nn bng phng php hi p ch ng. Trong trng hp ny nng lng in t chiu x mc tiu lm cho my tr li trn mc tiu pht ra nhng tn hiu v tuyn hon ton xc nh, nhng tn hiu ny c nhn bi my thu ca i Radar. Khi pht hin v o lng cc tham s ca mc tiu chng ta s dng nhng tnh cht vt l ca sng v tuyn: Sng in t trong mi trng ng nht v ng hng th truyn thng. Sng in t truyn vi tc trung bnh bng vn tc nh sang trong mi trung kh quyn v trong chn khng. Khi sng in t truyn lan trn mi trng ng nht nu gp phi mi trng th hai khng ng nht vi mi trng th nht (khng cng chit sut) th xy ra hin tng tn x sng in t. Hin tng tn x xy ra xung quanh mi trng th hai hay bin gii gia hai mi trng, ch c mt phn phn x v ngun pht x. Tia ny cng phng ngc chiu vi tia chiu x gip cho h thng pht hin c mc tiu, l i tng hay mc tiu cn nh v. Khi sng in t chiu x vo mc tiu ang chuyn ng vi mt tn s no gi l tn s chiu x th nng lng phn x v l tn hiu phn x c tn s sai khc so vi tn s chiu x.

f(chieuxa) f(doppler) = f(chieuxa) f = f(phanxa) Du + khi mc tiu tin dn v pha ngun chiu x. Du - khi mc tiu i xa ngun chiu x. f ph thuc vn tc xuyn tm do xc nh c f ta xc nh c vn tc xuyn tm. Hiu ng ny gi l hiu ng Doppler. 3. Ch tiu k thut chin thut ca Radar: 3.1. Ch tiu chin thut: Vng quan st: Radar c nhim v quan st mc tiu trong phm vi ny. Vng quan st gii hn bi c ly cc i Dmax v cc tiu Dmin v cc gc quan st trong mt phng ngang v ng. Chu k qut Tq: l thi gian Radar qut ht vng quan st mt ln. Cc ta c o. chnh xc o cc ta v tc mc tiu. tin cy s dng: tin cy nu ln kh nng hon thnh chc nng ca i trong mt khong thi gian xc nh. Thng thng tin cy c biu th bi xc sut i lm vic trong mt khong thi gian cho. Kh nng chng nhiu: l kh nng duy tr c cc ch tiu k thut ca i Radar trong iu khin c nhiu tc ng. V tnh nng chin thut i khi ngi ta cn k thm nhng iu kin lm vic ca i: tnh cht ca mc tiu, iu kin thi tit, v tr trin khai.. Cc tnh nng chin thut ca i radar xc nh bi tnh nng k thut ca n.

3.2.

Ch tiu k thut

Nguyn tc xy dng i Radar: phng php nhn tn hiu Radar, dng dao ng bc x, phng php gia cng tn hiu trong my thu.

Tn s sng mang ca dao ng bc x hay bc sng . Quy lut iu ch dao ng bc x. Cng sut bc x trung bnh Ptb v cng sut nh Pd. Dng v rng ca gin anten. nhy ca my thu theo cng sut Ptmin hay nng lng.

II. Phn loi h thng radar v di tn lm vic 1. Phn loi h thng radar H thng Radar ch ng (Active System): thc hin vic pht, thu v x l sng in t phn x t mc tiu radar. H thng Radar b ng (Passive System): ch thu v x l sng in t bc x t mc tiu Radar. H thng Radar lin tc (Continuous Wave):

H thng Radar xung (Pulse Radar):

Radar s cp: l h thng Radar thu nhn tn hiu phn x t b mt mc tiu n my pht t di mt t.

Radar th cp: l h thng Radar thu nhn cc tn hiu do mc tiu pht sau khi nhn c tn hiu t mt t.

2. Di tn lm vic ca h thng radar

III. ng dng. H thng Radar cho ta bit mc tiu (hay i tng) cn quan st qua mn hnh hin th:

Radar c th t trn mt t, trn mt bin, trong khng kh hay l trong khng gian. Radar mt t dng pht hin, nh v v bm cc my bay hoc mc tiu khng gian. Radar t trn tu s dng dn ng v gip cu h trn bin, hoc cng c th quan st my bay. Radar t trn my bay dng pht hin cc my bay, tu khc, chp nh mt t, pht hin bo, v cng dn ng. Trong khng gian, radar hng dn cc tu khng gian v gim st t xa bin v t lin. Cc vng ng dng chnh ca radar: + iu khin giao thng hng khng (ATC) + Dn ng cho my bay + An ton hng hi + Khng gian + Cm nhn t xa + Qun s + D bo thi tit

Vi nhng ng dng v chc nng vai tr to ln ca radar, n tht s quan trng trong nhiu lnh vc.

Mt s hnh nh v h thng radar

H thng radar trn mt t

H thng radar trn bin v trn tu

H thng radar di ng trn b

Sng bn tc s dng nguyn l lm vic radar

IV.

Phn mm m phng.

1. Cc chc nng chnh ca chng trnh: Hin th c 6 mc tiu cng mt lc bng 6 mu khc nhau. li du vt ca qu o mc tiu. Radar ch ng s cp. T ng bm st mt mc tiu bt k no (bm theo gc phng v). Ln lt m phng trn 4 trang mn hnh Hin th nhn vng. Hin th c ly D bng cch qut tia in t ng thng Hin th c ly D bng cch qut tia in t vng trn. Hin th c ly D bng cch qut tia in t xon c. Phi th hin c chnh xc theo mc tng dn. Radar t ng o chiu qut cnh sng.

2. Lu thc hin:

Bt u

S AI Q u t th n g SAI KT T H C Qut xo n NG

NG

SAI Q u t tr n

NG

o ch i u q u t

o ch i u qut

KO M c ti? u

o ch i u qut

KO C

KO M c ti? u M c ti? u C C H i n th c c th n g s c a m c ti u th e o q u t xo n c H i n th c c th n g s c a m c ti u theo q u t tr n

H i n th c c th n g s c a m c ti u th e o q u t th n g

3. Kt qu chng trnh m phng 4.

Mn hnh khi ng hin th vng trn

Mn hnh qut thng

Mn hnh qut trn

Phn cng cng vicCng vic chnh ca nhm: Xy dng phn mn thit k mn hnh hin th radar. Cng vic c th ca tng thnh vin trong nhm: - ng nh Nht: Tm hiu lp trnh Visual C# , tham gia vit code chnh chng trnh m phng, xy dng giao din chng trnh. - V Vn Sn: Tm hiu lp trnh Visual C# , tham gia vit code chnh chng trnh m phng, xy dng giao din chng trnh, vit bo co. - ng Quc Cng: Tm hiu lp trnh Visual C# , tham gia vit code chnh chng trnh m phng, xy dng giao din chng trnh, thit k slide.

TI LIU THAM KHO[1].

T hc lp trnh Visual C++ T c bn n nng cao Phm Cng Ng (ch bin), Phm Ngc Nam, Phm Tun Lng. K thut nh v & dn ng Phm Vn Tun Bi ging k thut nh v & dn ng Trng Tun

[2]. [3].

[4]. www.google.com.vn