diff --git a/telephony/java/android/telephony/PhysicalChannelConfig.java b/telephony/java/android/telephony/PhysicalChannelConfig.java
index b359ebed26839..fadf0e1b84d93 100644
--- a/telephony/java/android/telephony/PhysicalChannelConfig.java
+++ b/telephony/java/android/telephony/PhysicalChannelConfig.java
@@ -554,7 +554,8 @@ public final class PhysicalChannelConfig implements Parcelable {
         }
 
         public @NonNull Builder setFrequencyRange(int frequencyRange) {
-            if (!ServiceState.isFrequencyRangeValid(frequencyRange)) {
+            if (!ServiceState.isFrequencyRangeValid(frequencyRange)
+                    && frequencyRange != ServiceState.FREQUENCY_RANGE_UNKNOWN) {
                 throw new IllegalArgumentException("Frequency range: " + frequencyRange +
                         " is invalid.");
             }