The use of coaxial cable as a transmission line becomes increasingly detrimental as the operating frequency increases. Microwave and mmWave communication technologies employ waveguide transmission lines between the radio and antenna to overcome the electrical limitations of coaxial cable.
Internationally Standardised Waveguide Sizes
| IEC / EIA / UK Designation | Type | Frequency | Dimensions |
|---|---|---|---|
| R3 / WR2300 / WG00 | Rectangular | 0.32 to 0.49 GHz | 584.20 x 292.10 mm (W x H) |
| R4 / WR2100 / WG0 | Rectangular | 0.35 to 0.53 GHz | 533.40 x 266.70 mm (W x H) |
| R5 / WR1800 / WG1 | Rectangular | 0.41 to 0.62 GHz | 457.20 x 228.60 mm (W x H) |
| R6 / WR1500 / WG2 | Rectangular | 0.49 to 0.75 GHz | 381.00 x 190.50 mm (W x H) |
| R8 / WR1150 / WG3 | Rectangular | 0.64 to 0.98 GHz | 292.10 x 146.05 mm (W x H) |
| R9 / WR975 / WG4 | Rectangular | 0.76 to 1.15 GHz | 247.65 x 123.82 mm (W x H) |
| R12 / WR770 / WG5 | Rectangular | 0.96 to 1.46 GHz | 195.58 x 97.79 mm (W x H) |
| R14 / WR650 / WG6 | Rectangular | 1.13 to 1.73 GHz | 165.10 x 82.55 mm (W x H) |
| R18 / WR510 / WG7 | Rectangular | 1.45 to 2.20 GHz | 129.54 x 64.77 mm (W x H) |
| R22 / WR430 / WG8 | Rectangular | 1.72 to 2.61 GHz | 109.22 x 54.61 mm (W x H) |
| R26 / WR340 / WG9A | Rectangular | 2.17 to 3.30 GHz | 86.36 x 43.18 mm (W x H) |
| R32 / WR284 / WG10 | Rectangular | 2.60 to 3.95 GHz | 72.14 x 34.04 mm (W x H) |
| R40 / WR229 / WG11A | Rectangular | 3.22 to 4.90 GHz | 58.17 x 29.08 mm (W x H) |
| R48 / WR187 / WG12 | Rectangular | 3.94 to 5.99 GHz | 47.549 x 22.149 mm (W x H) |
| R58 / WR159 / WG13 | Rectangular | 4.64 to 7.05 GHz | 40.386 x 20.193 mm (W x H) |
| R70 / WR137 / WG14 | Rectangular | 5.38 to 8.17 GHz | 34.849 x 15.799 mm (W x H) |
| R84 / WR112 / WG15 | Rectangular | 6.57 to 9.99 GHz | 28.499 x 12.624 mm (W x H) |
| R100 / WR90 / WG16 | Rectangular | 8.20 to 12.50 GHz | 22.860 x 10.160 mm (W x H) |
| R120 / WR75 / WG17 | Rectangular | 9.84 to 15.00 GHz | 19.050 x 9.525 mm (W x H) |
| R140 / WR62 / WG18 | Rectangular | 11.90 to 18.00 GHz | 15.799 x 7.899 mm (W x H) |
| R180 / WR51 / WG19 | Rectangular | 14.50 to 22.00 GHz | 12.954 x 6.477 mm (W x H) |
| R220 / WR42 / WG20 | Rectangular | 17.60 to 26.70 GHz | 10.668 x 4.318 mm (W x H) |
| R260 / WR34 / WG21 | Rectangular | 21.70 to 33.00 GHz | 8.636 x 4.318 mm (W x H) |
| R320 / WR28 / WG22 | Rectangular | 26.30 to 40.00 GHz | 7.112 x 3.556 mm (W x H) |
| R400 / WR22 / WG23 | Rectangular | 32.90 to 50.10 GHz | 5.690 x 2.845 mm (W x H) |
| R500 / WR19 / WG24 | Rectangular | 39.20 to 59.60 GHz | 4.775 x 2.388 mm (W x H) |
| R620 / WR15 / WG25 | Rectangular | 49.80 to 75.80 GHz | 3.759 x 1.880 mm (W x H) |
| R740 / WR12 / WG26 | Rectangular | 60.50 to 91.90 GHz | 3.0988 x 1.5494 mm (W x H) |
| R900 / WR12 / WG26 | Rectangular | 73.80 to 112.00 GHz | 2.5400 x 1.2700 mm (W x H) |
| R1200 / WR8 / WG28 | Rectangular | 92.20 to 140.00 GHz | 2.0320 x 1.0160 mm (W x H) |