ITU-R BT ITU-R BT ( ) ITU-T J.61 (

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1 ITU-R BT.439- ITU-R BT.439- (26-2). ( ( ( ITU-T J.6 ( ITU-T J.6 ( (

2 ITU-R BT K : 5. ITU-R BT.24 :. ITU-T J.6. : T u ( ) () (S + L = M) :A :B :C : D :E :F :G :H :J :K :L :M :S :Tsy :Tlb :Tu :Tb :Tfp :Tbp

3 3 ITU-R BT.439- F E D C B. M S L.L J H G.L U(t) ( ) C (APL) T lb T u G G T fp T sy T bp F T b H M L B C D E F G J K S A t 439- Z. Z : Z Z 2 log Z + Z( f ) Z Z( f ) db : 2 log A A2 db

4 ITU-R BT A 2 A.. B. ) A..(.( M) (db) (db). r.m.s. L L (db). r.m.s.. (db) L.kHz Hz

5 5 ITU-R BT (db). L khz (db). L :. APL - ( D) -.( G) (2.3.3 ) (.3.3 ) (..3.3 ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )

6 ITU-R BT APL. APL APL APL. APL APL. APL APL ( S) APL

7 7 ITU-R BT APL. APL... APL (3.4.3 ) (2.4.3 ) / ( ) / ( ) ( ) ( ) (.4.3 ) (..4.3 ) ( ) ( ) ( ) 439-b. ( ) ( ).( ) ( ).4.3

8 ITU-R BT APL ( ). ( ) ) f c ( ).(ITU-R BT

9 9 ITU-R BT.439- / / / ( ) %5 APL..APL. APL F B 3 B 2 B A..dB

10 ITU-R BT dB 3 f c - db 4.f c L. 525 B 3 B B 3.(2 b ) (2 b 2 ) b 2 L b r.m.s

11 ITU-R BT.439- (2 2 ).. khz 2. db 2.( 2 3 ) ) (D) 5.((sin 2 ) 2 4.

12 ITU-R BT : 3 = i.4 (G2) 3 = i Ai ki A2 ki A2 ( 3 ) G2 G 625 G2 2i 3 2 i 2 :A :i = ki :. 525 G = ki. -.. ( ).G2 G D2.. ( ) %y %x+.. y x : (%) x = Amax A y = Amin A : x + y = Amax Amin A

13 3 ITU-R BT.439- :A.( ) 5 ( ) :A ( ) ( ) -y +x. y x. : ( ) x = Φ max Φ y = Φ min Φ : x + y = Φ max Φ min.( ) 5 ( ) :Φ :Φ : G2 G G - (4 3 b 5 ) G2 G G (4 3 b 6 ) APL 3/7 ). ( 525 4/

14 ITU-R BT : ( ) - -.(s/%) ( 4 3 (A )..( ) µs 25.b (6 ) B2 B3 625 (5 ) B µs. : ( ) ( 625 ) ns 4 - ( 525 ) ns ( ) B2 B3 625 B3.6 5 B B3 B2 )..( 6 5. K K.4 S 525..K

15 5 ITU-R BT G2 G G B2.F B2 F G2 G G G B F ns.f C / /.. ITU-T J.63.ITU-T J.63 ( B ).( 4 ) B3 A NTSC PAL -. (B-Y)

16 ITU-R BT NTSC M/PAL () 8 ± 9 ± 8 ± 8 ± 8 ±. PAL 6 ± 5 6 ± 5 6 ± 5 ITU-T BT.7 D2 F G APL - 2.( ) NTSC ().M/PAL A. -

17 7 ITU-R BT.439- ( A IRE. - ( (/ T ) IRE ( )

18 ITU-R BT FIGURE 5 Signal 625 B for 625-line Bsystems B Signal B Signal B2 B2 Signal B3 B3 V..93 µs 24 µs/26 µs % 9 sin : Half-amplitude duration: 2T 2T : 2T Time of rise: approximately 2T : 2T Time of rise: approximately 2T ns 83 = T - - MHz 6 -.ns = T MHz 5 MHz 6 Note For 6 MHz video bandwidth T = 83 ns, for 5 MHz video bandwidth T = ns.. ns B3 B2 Note 2 In France, the normal time of rise of B2 and B3 is approximately ns. Note 3 For 6 MHz contries the rise time of B2 is equal to T..T B2 FIGURE 6 6 Signal 525B for 525-line systems B Signal B B Signal B2 B2 B3 Signal B3 IRE scale units IRE 9 36 H µs sin 2 5 : Half-amplitude duration: ns ns : ns 25 Time of rise: approximately 25 ns : ns 25 Time of rise: approximately 25 ns 439-6

19 9 ITU-R BT.439- FIGURE 7 7 Signal 625 C for 625-line systems C V.86 C C2 % MHz. MHz 2. MHz 4. MHz 4.8 MHz 5.8 MHz µs. MHz 2,8 MHz,5 - Note Some former OIRT countries use.5 MHz and 2.8 MHz for the 2 nd and 3 rd bursts respectively FIGURE 8 8 Signal C 525 for 525-line systems C IRE scale units IRE C C MHz. MHz 2. MHz 3. MHz 3.58 MHz 4.2 MHz H

20 ITU-R BT V. FIGURE 9 9 Signal D 625 for 625-line systems D D Signal D % V µs ( a) D2 Signal D2 % f = 4.43 MHz ( b) µs -.µs 8,66 Note In full-field test signals, each tread of the staircase may have a duration of 8.66 µs

21 2 ITU-R BT.439- FIGURE IRE IRE scale units D Signal D Signal D for 525-line systems IRE 525 D IRE scale units 8 D2 Signal D2 f = 3.58 MHz 72 9 IRE 4 IRE units ( H 28 (IRE ) a) ( 38 ( H 28.IRE 2± 2 Note Vertical scales give signal amplitudes. In Fig. b), the tread levels (IRE units) are indicaded on the dashed line. Note 2 Sub-carrier amplitude is ±2 IRE units.. - b) -. FIGURE Signal F for 625-line systems 625 F 439- V %. sin 2.65 : Half-amplitude µs 2. duration: 2. µs 5 f = 4.43 MHz

22 ITU-R BT F 2 FIGURE 2 Signal F for 525-line systems IRE scale units IRE sin 2 5 : Half-amplitude duration: µs,57.57 µs f = 3.58 MHz FIGURE 3 Signal 625 G for 625-line Gsystems V. G Signal G Signal G2 G2 % V. % f = 4.43 MHz b 5 b 6 f = 4.43 MHz.72 b b µs µs 439-3

23 23 ITU-R BT.439- IRE scale units IRE 9 FIGURE 4 4 Signal 525G for 525-line systems G f = 3.58 MHz b 5 b H FIGURE 5 5 Low-pass filter diagram L L2 L3 f f 2 f 3 75 Ω C C2 C3 75 Ω C4 C5 C6 C

24 ITU-R BT (MHz 5 = fc) f 5.56 f f3.mhz pf µη %2 ± MHz 5 Q - 4 C C2 C3 C4 C5 C6 C7 L L2 L3 5 6 FIGURE 6 Low-pass filter characteristic (db) Relative insertion loss (db) Frequency (MHz) (MHz) 439-6

25 25 ITU-R BT.439- (khz = fc).. 2 FIGURE 7 7 Combined filter design diagram A C C2 B 75 Ω L L2 75 Ω L3 L4 C C3 C4 75 Ω A: input B: high-pass output C: low-pass output :A :B :C C ±5% 96 C2 335 C3 8 2 C4.757 L ±2% 3.2 L2.83 L3.29 L4.pF.mH - Q - 2.kHz

26 ITU-R BT FIGURE 8 Combined filter characteristic 6 5 (db) Insertion loss (db) Frequency (MHz) (khz) FIGURE 9 9 Network diagram L R L = Z τ τ C = Z R = a Z Z = 75 Ω Z R2 Z Z = 75 Ω R 2 = Z a C 439-9

27 27 ITU-R BT.439- A ϖ τ log a A = 2 + ϖ τ a A 2 log ( + a) (A 4.8 db) db : : ns 245 = τ 4,5 = a FIGURE 2 2 Unified weighting characteristic A (db) f (MHz) db 2,2 : MHz 5 db 7,4 :

28 ITU-R BT FIGURE 2 2 Non-constant resistance network diagram µh Input.9 µh pf f 3 Output f 75 Ω pf 75 Ω 75 Ω 75 Ω µh (R <.5 Ω) f 2 99 pf 47 pf 8 35 pf f = 6. khz f 2 = 6. khz f 3 = 55.8 khz - Note Capacitor and resistor tolerances ±%..%±. - 2 Note 2 Each inductor should be adjusted to resonate at the appropriate indicated frequency. 3. Ω 75 - Note 3 This network requires to be operated between 75 Ω terminations for correct performance FIGURE 22 Constant resistance network diagram 2.4 Input.2 µh 6 26 pf µh 6.25 µh Output pf 2. µh 75 Ω 75 Ω 75 Ω 66.6 Ω 62 Ω 3.8 µh 75 Ω µh 989 pf µh 2 87 pf 4 8 pf 3 47 pf Q %2± -.%± Note Capacitor and inductor tolerances ±2%, resistor tolerance ±%. The Q-factor of each inductor should be equal to, or greater than, 8 at MHz..MHz

29 29 ITU-R BT FIGURE Transient response of the network Output voltage (V) (V) (µs) Time (µs) FIGURE Thomson filter diagram L L3 L4 75 Ω C3 C L2 C4 C5 75 Ω C

30 ITU-R BT pF Phillips, Proc. IEE, (f = 3.3 MHz) / C C2 C3 C4 C5 L L2 - µh - : - f 2 3.Vol. 5B, p ITU-T J.63 FIGURE Line 7 for 625-line systems V. B2 b 3 b 2 b 4 B F D % b H

31 3 ITU-R BT FIGURE 26 Line 525 7/field for 525-line /7 systems IRE scale IRE units 9 B2 b 3 b 2 b 4 B F D2 b 2 4 (O H ) 24 H/ H (O HR ) K - K : K T sin 2 K..

32 ITU-R BT K (B3 B2) (B) 2T sin 2. /2 F c = T T..( F c ) ns 8±.K (2T) ( 27 ( 27 K± ns 4± K2± ns 2± :( 27 ( 27 K (2T) = 3% : K (P/B) 2T 2.2 K4± ( 27.( 27 /2T (P/B) B K( P / B) = % 4 P T 2.2 /2T - 2T.. T 3.2 (MHz 6 = f c ( 27 ( 625) B ns 67 MHz 5 = f c ns 2 = 2T : ) % %3± %6± %2± %2± %6± %3± 8T 4T 2T 2T 4T 8T ns

33 33 ITU-R BT.439- ( 525) B (ns 25 ( 27 : ) % %3± %6± %2± %2± %6± %3± ns T T...(,82 y ) y. : K (T). B K( T ) = y 4 P.K (T). 3K (T) ( ). T...K : : [½ B(rT ) =... B r,... B, B, B +,... B + r,... ½] B(rT) = B C(rT) =... C r,... C, C, C +,... C + r,... 3

34 ITU-R BT Cr = Br + Br + Br+ 2 2 : : K 8 C r r C K Cr C for 8 r 2 and + 2 r + 8 for r 8 and r + 8 : 8 2 = 4 + K B r C = 6 + K B r 8 = + 8 K B r K (2T) K.2T C(rT) K3. K (P/B) 2T K2. - K4. K (T) 6..

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