Insertion loss and Conversion chart Between Return Loss and VSWR

Author : handsun co Date : 12/15/2013 3:51:45 PM

Return loss is another specification of interest. This parameter is used to specify the forward loss characteristics of a circulator or isolator. Most catalog models have an insertion loss specification of 0.25dB to 0.5dB. Many low noise systems require an isolator with as low an insertion loss as possible. For these applications the insertion loss can be minimized by using low loss ferrite and dielectric materials. Losses as low as 0.1dB have been provided in large production quantities.

Here conversion is between return loss and VSWR, and some values are tabulated below, along with a graph of these values for quick reference.

CONVERSION CHART BETWEEN RETURN LOSS AND VSWR
VSWR	RETURN LOSS	Trans.Loss	Volt.Refl.	Power Trans.	VSWR	RETURN LOSS	Trans.Loss	Volt.Refl.	Power Trans.
NUMBER	(dB)	(dB)	Coeff	(%)	NUMBER	(dB)	(dB)	Coeff	(%)
1.00	∞	0.000	0.00	100.0	1.54	13.4	0.201	0.21	95.5
1.01	46.1	0.000	0.00	100.0	1.56	13.2	0.213	0.22	95.2
1.02	40.1	0.000	0.01	100.0	1.58	13.0	0.225	0.22	94.9
1.03	36.6	0.001	0.01	100.0	1.60	12.7	0.238	0.23	94.7
1.04	34.2	0.002	0.02	100.0	1.62	12.5	0.250	0.24	94.4
1.05	32.3	0.003	0.02	99.9	1.64	12.3	0.263	0.24	94.1
1.06	30.7	0.004	0.03	99.9	1.66	12.1	0.276	0.25	93.8
1.07	29.4	0.005	0.03	99.9	1.68	11.9	0.289	0.25	93.6
1.08	28.3	0.006	0.04	99.9	1.70	11.7	0.302	0.26	93.3
1.09	27.3	0.008	0.04	99.8	1.72	11.5	0.315	0.26	93.0
1.10	26.4	0.010	0.05	99.8	1.74	11.4	0.329	0.27	92.7
1.11	25.7	0.012	0.05	99.7	1.76	11.2	0.342	0.28	92.4
1.12	24.9	0.014	0.06	99.7	1.78	11.0	0.356	0.28	92.1
1.13	24.3	0.016	0.06	99.6	1.80	10.9	0.370	0.29	91.8
1.14	23.7	0.019	0.07	99.6	1.82	10.7	0.384	0.29	91.5
1.15	23.1	0.021	0.07	99.5	1.84	10.6	0.398	0.30	91.3
1.16	22.6	0.024	0.07	99.5	1.86	10.4	0.412	0.30	91.0
1.17	22.1	0.027	0.08	99.4	1.88	10.3	0.426	0.31	90.7

1.18	21.7	0.030	0.08	99.3	1.90	10.2	0.440	0.31	90.4
1.19	21.2	0.033	0.09	99.2	1.92	10.0	0.454	0.32	90.1
1.20	20.8	0.036	0.09	99.2	1.94	9.9	0.468	0.32	89.9
1.21	20.4	0.039	0.10	99.1	1.96	9.8	0.483	0.32	89.5
1.22	20.1	0.043	0.10	99.0	1.98	9.7	0.497	0.33	89.2
1.23	19.7	0.046	0.10	98.9	2.00	9.5	0.512	0.33	88.9
1.24	19.4	0.050	0.11	98.9	2.50	7.4	0.881	0.43	81.6
1.25	19.1	0.054	0.11	98.8	3.00	6.0	1.249	0.50	75.0
1.26	18.8	0.058	0.12	98.7	3.50	5.1	1.603	0.56	69.1
1.27	18.5	0.062	0.12	98.6	4.00	4.4	1.938	0.60	64.0
1.28	18.2	0.066	0.12	98.5	4.50	3.9	2.255	0.64	59.5
1.29	17.9	0.070	0.13	98.4	5.00	3.5	2.553	0.67	55.6
1.30	17.7	0.075	0.13	98.3	5.50	3.2	2.834	0.69	52.1
1.32	17.2	0.083	0.14	98.1	6.00	2.9	3.100	0.71	49.0
1.34	16.8	0.093	0.15	97.9	6.50	2.7	3.351	0.73	46.2
1.36	16.3	0.102	0.15	97.7	7.00	2.5	3.590	0.75	43.7
1.38	15.9	0.112	0.16	97.5	7.50	2.3	3.817	0.76	41.5
1.40	15.6	0.122	0.17	97.2	8.00	2.2	4.033	0.78	39.5
1.42	15.2	0.133	0.17	97.0	8.50	2.1	4.240	0.79	37.7
1.44	14.9	0.144	0.18	96.7	9.00	1.9	4.437	0.80	36.0
1.46	14.6	0.155	0.19	96.5	9.50	1.8	4.626	0.81	34.5
1.48	14.3	0.166	0.19	96.3	10.00	1.7	4.807	0.82	33.1
1.50	14.0	0.177	0.20	96.0	11.00	1.6	5.149	0.83	30.6
1.52	13.7	0.189	0.21	95.7	12.00	1.5	5.466	0.85	28.4