Hold a wifi lock to prevent sleep from affecting wifi speed.

app/src/main/AndroidManifest.xml

@@ -10,6 +10,7 @@
 	<uses-permission android:name="android.permission.BLUETOOTH" />
 	<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
 	<uses-permission android:name="android.permission.INTERNET" />
+	<uses-permission android:name="android.permission.WAKE_LOCK" />
 
 	<uses-permission-sdk-23 android:name="android.permission.ACCESS_COARSE_LOCATION" />
 

app/src/main/java/org/briarproject/interferometer/MainViewModel.java

@@ -9,6 +9,8 @@ import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.net.wifi.WifiManager;
+import android.net.wifi.WifiManager.WifiLock;
 import android.os.Bundle;
 import android.util.Log;
 
@@ -38,6 +40,8 @@ import static android.bluetooth.BluetoothAdapter.ACTION_STATE_CHANGED;
 import static android.bluetooth.BluetoothAdapter.EXTRA_STATE;
 import static android.bluetooth.BluetoothAdapter.STATE_OFF;
 import static android.bluetooth.BluetoothAdapter.STATE_ON;
+import static android.content.Context.WIFI_SERVICE;
+import static android.net.wifi.WifiManager.WIFI_MODE_FULL_HIGH_PERF;
 import static java.util.concurrent.Executors.newCachedThreadPool;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static org.briarproject.interferometer.MainViewModel.ConnectionState.DISCONNECTED;
@@ -117,9 +121,18 @@ public class MainViewModel extends AndroidViewModel {
 		if (hostPort == null) return INVALID_ADDRESS;
 		BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
 		if (adapter == null) return NO_BLUETOOTH;
+
 		Log.i(TAG, "Starting test");
 		task = executorService.submit(() -> {
+			WifiLock wifiLock = null;
 			try {
+				WifiManager wifiManager = (WifiManager)
+						getApplication().getApplicationContext().getSystemService(WIFI_SERVICE);
+				if (wifiManager != null) {
+					wifiLock = wifiManager.createWifiLock(WIFI_MODE_FULL_HIGH_PERF, TAG);
+					wifiLock.acquire();
+				}
+
 				if (!disableBluetooth(adapter)) {
 					Log.w(TAG, "Failed to disable Bluetooth");
 					return;
@@ -166,7 +179,6 @@ public class MainViewModel extends AndroidViewModel {
 					adapter.disable();
 				}
 
-
 				Log.i(TAG, "Test finished");
 				Bundle b = new Bundle();
 				b.putDouble(DOWNLOAD_DISABLED, mean(downloadDisabled));
@@ -180,6 +192,7 @@ public class MainViewModel extends AndroidViewModel {
 				b.putBoolean(CONSUMED, false);
 				results.postValue(b);
 			} finally {
+				if (wifiLock != null) wifiLock.release();
 				testPhase.postValue(READY);
 			}
 		});