Waveguide dimensions

Updated August 28, 2006

Our other info on waveguide can be found on these pages:

Waveguide primer (main waveguide page)

Waveguide mathematics

Waveguide construction

Waveguide loss calculation

We've fixed some small errors in our rectangular waveguide table of dimensions below. Thanks, Dane! Thanks to Steve from Chile, for also pointing out where we were wrong! We've now referenced some of the dimensional info from Penn Engineering, and also a combination of material borrowed from Maury Microwave and ZAX Millimeter Wave Corporation web sites. The lower seven waveguide series were contributed by "Nameless Individual" from LockMart.

Although there are disagreements between waveguide vendors, our table is representative of the US system (other countries such as the U.K. have their own crappy nomenclature that is just as confusing). Note that two letters (F and G) are used twice in the table, illustrating the lack of industry-wide agreement.

The interior of a standard rectangular waveguide has a 2:1 aspect ratio, that is, the broad wall is twice the dimension of the narrow wall, or very nearly so. Rectangular waveguides support E-M waves only over a certain frequency band, depending on the cross-sectional dimensions. The bigger the size of the waveguide, the lower in frequency it works. Waveguides are specified in WR numbers. WR stands for "rectangular waveguide" except the military long ago decided that all adjectives must follow nouns for some reason.

Word of caution: depending on what reference you use, we have seen some disagreement in the height of the waveguide dimension, especially on the larger waveguide series such as WR650.

Waveguide frequency bands and dimensions
Frequency Band	Waveguide Standard	Frequency Limits (GHz)	Inside Dimensions (inches)
	WR-2300	0.32 - 0.49	23.000 x 11.500
	WR-2100	0.35 - 0.53	21.000 x 10.500
	WR-1800	0.43 - 0.62	18.000 x 9.000
	WR-1500	0.49 - 0.74	15.000 x 7.500
	WR-1150	0.64 - 0.96	11.500 x 5.750
	WR-1000	0.75 - 1.1	9.975 x 4.875
	WR-770	0.96 - 1.5	7.700 x 3.385
	WR-650	1.12 to 1.70	6.500 x 3.250
R band	WR-430	1.70 to 2.60	4.300 x 2.150
D band	WR-340	2.20 to 3.30	3.400 x 1.700
S band	WR-284	2.60 to 3.95	2.840 x 1.340
E band	WR-229	3.30 to 4.90	2.290 x 1.150
G band	WR-187	3.95 to 5.85	1.872 x 0.872
F band	WR-159	4.90 to 7.05	1.590 x 0.795
C band	WR-137	5.85 to 8.20	1.372 x 0.622
H band	WR-112	7.05 to 10.00	1.122 x 0.497
X band	WR-90	8.2 to 12.4	0.900 x 0.400
Ku band	WR-62	12.4 to 18.0	0.622 x 0.311
K band	WR-51	15.0 to 22.0	0.510 x 0.255
K band	WR-42	18.0 to 26.5	0.420 x 0.170
Ka band	WR-28	26.5 to 40.0	0.280 x 0.140
Q band	WR-22	33 to 50	0.224 x 0.112
U band	WR-19	40 to 60	0.188 x 0.094
V band	WR-15	50 to 75	0.148 x 0.074
E band	WR-12	60 to 90	0.122 x 0.061
W band	WR-10	75 to 110	0.100 x 0.050
F band	WR-8	90 to 140	0.080 x 0.040
D band	WR-6	110 to 170	0.0650 x 0.0325
G band	WR-5	140 to 220	0.0510 x 0.0255
	WR-4	170 to 260	0.0430 x 0.0215
	WR-3	220 to 325	0.0340 x 0.0170
Y-band	WR-2	325 to 500	0.0200 x 0.0100
	WR-1.5	500 to 750	0.0150 x 0.0075
	WR-1	750 to 1100	0.0100 x 0.0050

Waveguide dimension rule of thumb

How do you know what WR number a waveguide is just by looking at it? The number is simply the dimension of the broad wall in mils, divided by 10. Thus the waveguide depicted below is WR-62 (if you look closely at the caliper it indicates 620 mils), which is used in Ku-band.