1、 GY/T 172 2001 MMDS Specification and methods of measurement on MMDS receiving antenna 2001-07-18 2001-10-01 GY/T 132 1998 MMDS A GY/T 1722001 17 1 2500MHz 2700MHz MMDS MMDS 2 GB/T 7400 1987 GB/T 7615 1987 GB/T 14733.10 1993 GY/T 132 1998 3 3.1 antenna 3.2 antenna gain P E P0 E0 G 0 P P G 10log = dB
2、 0 E E G 20log = dB 3.3 polarization a) b) MMDS GY/T 172 2001 Specifications and methods of measurement on MMDS receiving antenna 2001-07-18 2001-10-01 GY/T 172-2001 18 3.4 power flux density mW/cm 2 3.5 radiation pattern 3.6 radiation lobe 3.7 major lobe main lobe 3.8 secondary lobe 3.9 back lobe 1
3、80 3.10 side lobe 3.11 front to back ratio dB 3.12 (relative) side-lobe level (for a specified polarization) dB 3.13 bandwidth of antenna 3.14 gain bandwidth of antenna 3.15 polarization isolation of antenna dB polarization decoupling ratio of antenna 3.16 VSWR( ) output VSWR of antenna SWR 1 VSWR 1
4、 VSWR + = VSWR 1 VSWR 1 VSWR 20log R + = L VSWR LR VSWR VSWR 3.17 return loss LR LR 20log dB 1 VSWR 1 VSWR 20log R + = L (dB) GY/T 172-2001 19 3.18 anechoic enclosure 4 1 1 1 f MHz 25002700 2 Z0 50 N 3 LR dB 16 4 Gfla dB 1.5 5 p dB 20 6 LW N/m 2 300 7 G dB 21 24 8 Ab dB -17 -19 9 k dB 18 20 5 5.1 1d
5、B V/m /2 1dB V/m 5.2 D rmin 1 rmin (3 5) (cm m) 1 D rmin 2 rmin 2D 2(cm m) 2 5.3 0.01 GHz 3 GHz 1% GY/T 172-2001 20 0.3dB 5.4 5.4.1 1 75 75 50 T R r r 1 2 1 5.4.2 5.4.2.1 1 30 5.4.2.2 PRESET START 2500MHz STOP 2700MHz 5.4.2.3 5.4.2.4 50 N 50 5.4.2.5 5.4.2.6 50 r A1 r/r = 2% 5.4.2.7 5.4.2.8 2500MHz 2
6、700MHz Grmax Grmin 0.2dB A1 3 Gfla 0.2dB A1 ) ( fla rmin rmax 2 1 G G G = dB 3 5.4.2.9 2500MHz 2700MHz 2500 MHz 50 50 R T r GY/T 172-2001 21 2600MHz 2700MHz Gr 0.2dB A1 4 G 0.2dB A1 = r 4 r 10log G G 2 1 dB 4 5.5 VSWR 5.5.1 VSWR 2 75 75 50 2 50 50 2 VSWR 5.5.2 5.5.2.1 2 30 5.5.2.2 PRESET START 2500M
7、Hz STOP 2700MHz 5.5.2.3 5.5.2.4 5.5.2.5 5.5.2.6 2500MHz 2700MHz 0.2dB 0.01 A2 5.6 5.6.1 1 R T 5.6.2 5.6.2.1 5.4.2.1 5.4.2.7 r 5.6.2.2 2500MHz 2700MHz 2500MHz ( ) 50 GY/T 172-2001 22 Gr0 0.2dB A3 5.6.2.3 2500MHz GrR 0.2dB A3 5 AbR 0.2dB A3 AbR = Gr0 - GrR dB 5 5.6.2.4 Gr0 GrL 0.2dB A3 6 AbL 0.2dB A3
8、ABl = Gr0 - GrL dB 6 5.6.2.5 5.6.2.2 5.6.2.4 2600MHz 2700MHz A3 5.6.2.6 2500MHz 180 180 60 Gf 0.2dB A3 7 k 0.2dB A3 k = Gr0 - Gf dB 7 5.6.2.7 5.6.2.6 2600MHz 2700MHz A3 5.6.2.8 2500MHz 90 Gp 0.2dB A3 (8) p 0.2dB A3 p = Gr0 - Gp dB 8 5.6.2.9 5.6.2.8 2600MHz 2700MHz GY/T 172-2001 23 A ( ) A1 MHz cm r m Gr dB G dB Grmax dB Grmin dB Gfla dB 2500 12.00 2600 11.54 2700 11.11 A2 VSWR dB VSWR A3 MHz Gr0 dB GrR dB GrL dB Gf dB Gp dB AbR dB AbL dB k dB p dB 2500 2600 2700
