 
A few basic facts about waveguide: Here are Waveguide Equations & Fields - The "WR" designation stands for "waveguide, rectangular"
- The wide inside dimension in inches is the "xxx" part of WRxxx; ie, WR650 is 6.50 inches, WR90 is 0.90 inches.
- The TE10 mode of propagation is the lowest mode that is supported.
- The waveguide width determines the lower cutoff frequency and is equal (ideally) to ½ wavelength of the lower cutoff frequency.
- The TE20, occurs when the width equals one wavelength of the lower cutoff frequency, and so on for higher modes.
- The TE01 mode occurs when the height equals ½ wavelength of the cutoff frequency, and so on to higher modes.
- Click here for waveguide formulas.
| H-Bend | E-Bend | 
An H-Bend is bent in the Hard direction (along the long side). This is the direction of the H-field in the TE10 mode. | 
An E-Bend is bent in the Easy direction (along the short side). This is the direction of the E-field in the TE10 mode. |
| | | Standard Rectangular Waveguide | Click here for handy free "ezGuide" waveguide selector software from Andrew. | | |
Designation
(a)=aluminum, (b)=brass, (c)=copper, (s)=silver | fL - fU*
(GHz) | fCO**
(GHz) | Inside
Width
(in) | Inside
Height
(in) | | WR | U.S. Mil.
__ /U | British
Mil. | IEC | | WR975 | RG204 (a) | | | 0.75-1.12 | 0.605 | 9.750 | 4.875 | | WR770 | RG205 (a) | | | 0.96-1.45 | 0.766 | 7.700 | 3.850 | | WR650 | RG69 (b)
RG103 (a) | WG6 | | 1.12-1.70 | 0.908 | 6.500 | 3.250 | | WR510 | | | | 1.45-2.20 | 1.157 | 5.100 | 2.550 | | WR430 | RG104 (b)
RG105 (a) | WG8 | | 1.70-2.60 | 1.372 | 4.300 | 2.150 | | WR340 | RG112 (b)
RG113 (a) | WG9A | | 2.20-3.30 | 1.736 | 3.400 | 1.700 | | WR284 | RG48 (b)
RG75 (a) | WG10 | | 2.60-3.95 | 2.078 | 2.840 | 1.340 | | WR229 | RG340 (c)
RG341 (a) | WG11A | R40 | 3.30-4.90 | 2.577 | 2.290 | 1.145 | | WR187 | RG49 (b)
RG95 (a) | WG12 | R48 | 3.95-5.85- | 3.152 | 1.872 | 0.872 | | WR159 | RG343 (c)
RG344 (a) | WG13 | R58 | 4.90-7.05 | 3.712 | 1.590 | 0.795 | | WR137 | RG50 (b)
RG106 (a) | WG14 | R70 | 5.850-8.200 | 4.301 | 1.372 | 0.622 | | WR112 | RG51 (b)
RG68 (a) | WG15 | R84 | 7.050-10.000 | 5.260 | 1.122 | 0.497 | | WR90 | RG52 (b)
RG67 (a) | WG16 | R100 | 8.20-12.40 | 6.56 | 0.900 | 0.400 | | WR75 | RG346 (c)
RG347 (a) | WG17 | | 10.0-15.0 | 7.87 | 0.750 | 0.375 | | WR62 | RG91 (b)
RG349 (a) | WG18 | | 12.40-18.00 | 9.49 | 0.622 | 0.311 | | WR51 | RG352 (c)
RG351 (a) | WG19 | | 15.00-22.00 | 11.6 | 0.510 | 0.255 | | WR42 | RG53 (b)
RG121 (a) | WG20 | | 18.00-26.5 | 14.1 | 0.420 | 0.170 | | WR34 | RG354 (c) | | | 20.0-33.0 | 17.4 | 0.340 | 0.170 | | WR28 | RG96 (s)
RG271 (c) | WG22 | | 26.50-40.00 | 21.1 | 0.280 | 0.140 | | WR22 | RG97 (s) | WG23 | | 33.00-50.00 | 26.4 | 0.224 | 0.112 | | WR19 | | WG24 | | 40.00-60.00 | 31.4 | 0.188 | 0.0940 | | WR15 | RG98 (s) | WG25 | | 50.00-75.00 | 39.9 | 0.148 | 0.0740 | | WR12 | RG99 (s) | WG26 | | 60.00-90.00 | 48.4 | 0.122 | 0.0610 | | WR10 | | WG27 | | 75.00-110.0 | 59.0 | 0.100 | 0.0500 | | WR8 | RG138 (s) | WG28 | | 90.00-140.0 | 73.8 | 0.0800 | 0.0400 | | WR7 | RG136 (s) | | | 110.0-170.0 | 90.8 | 0.0650 | 0.0325 | | WR4 | RG137 | | | 170.0-260.0 | 137 | 0.0430 | 0.0215 | | WR3 | RG139 (s) | | | 220.0-325.0 | 174 | 0.0340 | 0.0170 |
* Per standard manufacturer's specifications
** Cutoff frequencies calculated per standard rectangular waveguide equation.
| | Double-Ridge Waveguide | | Double-ridge waveguide provides a wider operational bandwidth at the cost of higher insertion loss and lower power handling. The "D" in WRD stands for double-ridge. D24 at the end means a bandwidth ration of 1.24:1, etc. | | |
Designation
(a) = aluminum, (b) = brass, (c) = copper | fL - fU
(GHz) | fCO
(GHz) | Maximum
Inside
Width
(in) | Maximum
Inside
Height
(in) | | WRD | U.S. Mil.
MIL-W-23351- | | WRD250 | - | 2.60-7.80 | 2.093 | 1.655 | 0.715 | | WRD350 D24 | 4-029 (a)
4-303 (b)
4-031 (c) | 3.50-8.20 | 2.915 | 1.480 | 0.688 | | WRD475 D24 | 4-033 (a)
4-034 (b)
4-035 (c) | 4.75-11.0 | 3.961 | 1.090 | 0.506 | | WRD500 D36 | 2-025 (a)
2-026 (b)
2-027 (c) | 5.00-18.00 | 4.222 | 0.752 | 0.323 | | WRD650 | - | 6.50-18.00 | 5.348 | 0.721 | 0.321 | | WRD750 D24 | 4-037 (a)
4-038 (b)
4-039 (c) | 7.50-18.00 | 6.239 | 0.691 | 0.321 | | WRD110 D24 | 4-041 (a)
4-042 (b)
4-043 (c) | 11.00-26.50 | 9.363 | 0.471 | 0.219 | | WRD180 D24 | 4-045 (a)
4-046 (b)
4-047 (c) | 18.00-40.00 | 14.995 | 0.288 | 0.134 |
| North American Waveguide Flange Shapes | IEC Waveguide Flange Shapes | 
Contact Grooved | 
CPR | 
CMR | 
CAR |
UDR |
UER | 
Square Cover | 
Round Cover | 
CPR Grooved |
UBR |
UAR |
PDR | 
Choke | 
Square Cover
Grooved | 
Round Cover
Grooved |
CBR |
PBR |
PAR |
Flange Style Designations - UG: UG is the military standard MIL-DTL-3922 for a range of flange types.
- CMR: CMR flanges are the miniature version of the Connector Pressurized Rectangular
(CPR) style flanges. - CPRG: Connector Pressurized Rectangular (CPR) refers to a range of commercial
rectangular flanges. CPRG is Grooved CPR flange. - CPRF: Connector Pressurized Rectangular (CPR) refers to a range of commercial
rectangular flanges. CPRF is flat CPR flange. - Cover or Plate: Square, flat UG style flanges.
- Choke: UG style flanges with an o-ring groove and a choke cavity.
| 
Kirt
