diff --git a/gnss/3.0/default/GnssPsds.h b/gnss/3.0/default/GnssPsds.h
new file mode 100644
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+++ b/gnss/3.0/default/GnssPsds.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <android/hardware/gnss/3.0/IGnssPsds.h>
+#include <hidl/MQDescriptor.h>
+#include <hidl/Status.h>
+
+namespace android::hardware::gnss::V3_0::implementation {
+
+using ::android::sp;
+using ::android::hardware::hidl_array;
+using ::android::hardware::hidl_memory;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+
+struct GnssPsds : public V3_0::IGnssPsds {
+    // Methods from V1_0::IGnssXtra follow.
+    Return<bool> setCallback(const sp<V1_0::IGnssXtraCallback>& callback) override;
+    Return<bool> injectXtraData(const hidl_string& xtraData) override;
+
+    // Methods from V3_0::IGnssPsds follow.
+    Return<bool> setCallback_3_0(const sp<V3_0::IGnssPsdsCallback>& callback) override;
+    Return<bool> injectPsdsData_3_0(int32_t psdsType, const hidl_string& psdsData) override;
+
+  private:
+    // Guarded by mMutex
+    static sp<V3_0::IGnssPsdsCallback> sCallback_3_0;
+
+    // Synchronization lock for sCallback_3_0
+    mutable std::mutex mMutex;
+};
+
+}  // namespace android::hardware::gnss::V3_0::implementation