RssiRadioSourceEstimator3D.java
/*
* Copyright (C) 2018 Alberto Irurueta Carro (alberto@irurueta.com)
*
* 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.
*/
package com.irurueta.navigation.indoor.radiosource;
import com.irurueta.geometry.InhomogeneousPoint3D;
import com.irurueta.geometry.Point3D;
import com.irurueta.navigation.indoor.Beacon;
import com.irurueta.navigation.indoor.BeaconWithPowerAndLocated3D;
import com.irurueta.navigation.indoor.RadioSource;
import com.irurueta.navigation.indoor.RadioSourceWithPowerAndLocated;
import com.irurueta.navigation.indoor.RssiReadingLocated;
import com.irurueta.navigation.indoor.WifiAccessPoint;
import com.irurueta.navigation.indoor.WifiAccessPointWithPowerAndLocated3D;
import java.util.List;
/**
* Estimates 3D position and transmitted power of a radio source assuming that the
* radio source emits isotropically following the expression below:
* Pr = Pt*Gt*Gr*lambda^2 / (4*pi*d)^2,
* where Pr is the received power (expressed in mW),
* Gt is the Gain of the transmission antenna
* Gr is the Gain of the receiver antenna
* d is the distance between emitter and receiver
* and lambda is the wavelength and is equal to: lambda = c / f,
* where c is the speed of light
* and f is the carrier frequency of the Wi-Fi signal.
* Because usually information about the antenna of the radio source cannot be
* retrieved (because many measurements are made on unknown radio sources where
* physical access is not possible), this implementation will estimate the
* equivalent transmitted power as: Pte = Pt * Gt * Gr.
* If Readings contain RSSI standard deviations, those values will be used,
* otherwise it will be assumed an RSSI standard deviation of 1 dB.
* <p>
* IMPORTANT: Implementations of this class can choose to estimate a
* combination of radio source position, transmitted power and path loss
* exponent. However enabling all three estimations usually achieves
* inaccurate results. When using this class, estimation must be of at least
* one parameter (position, transmitted power or path loss exponent) when
* initial values are provided for the other two, and at most it should consist
* of two parameters (either position and transmitted power, position and
* path loss exponent or transmitted power and path loss exponent), providing an
* initial value for the remaining parameter.
*
* @param <S> a {@link RadioSource} type.
*/
public class RssiRadioSourceEstimator3D<S extends RadioSource> extends RssiRadioSourceEstimator<S, Point3D> {
/**
* Constructor.
*/
public RssiRadioSourceEstimator3D() {
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(final List<? extends RssiReadingLocated<S, Point3D>> readings) {
super(readings);
}
/**
* Constructor.
*
* @param listener listener in charge of attending events raised by this instance.
*/
public RssiRadioSourceEstimator3D(final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param listener listener in charge of attending events raised by this instance.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings,
final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(readings, listener);
}
/**
* Constructor.
*
* @param initialPosition initial position to start the estimation of radio
* source position.
*/
public RssiRadioSourceEstimator3D(final Point3D initialPosition) {
super(initialPosition);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialPosition initial position to start the estimation of radio
* source position.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Point3D initialPosition) {
super(readings, initialPosition);
}
/**
* Constructor.
*
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param listener listener in charge of attending events raised by this instance.
*/
public RssiRadioSourceEstimator3D(
final Point3D initialPosition, final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(initialPosition, listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param listener listener in charge of attending events raised by this instance.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Point3D initialPosition,
final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(readings, initialPosition, listener);
}
/**
* Constructor.
*
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
*/
public RssiRadioSourceEstimator3D(final Double initialTransmittedPowerdBm) {
super(initialTransmittedPowerdBm);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Double initialTransmittedPowerdBm) {
super(readings, initialTransmittedPowerdBm);
}
/**
* Constructor.
*
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param listener listener in charge of attending events raised by this instance.
*/
public RssiRadioSourceEstimator3D(
final Double initialTransmittedPowerdBm, final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(initialTransmittedPowerdBm, listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param listener listener in charge of attending events raised by this instance.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Double initialTransmittedPowerdBm,
final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(readings, initialTransmittedPowerdBm, listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of access point transmitted power
* (expressed in dBm's)
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Point3D initialPosition,
final Double initialTransmittedPowerdBm) {
super(readings, initialPosition, initialTransmittedPowerdBm);
}
/**
* Constructor.
*
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
*/
public RssiRadioSourceEstimator3D(
final Point3D initialPosition, final Double initialTransmittedPowerdBm) {
super(initialPosition, initialTransmittedPowerdBm);
}
/**
* Constructor.
*
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param listener listener in charge of attending events raised by this instance.
*/
public RssiRadioSourceEstimator3D(
final Point3D initialPosition, final Double initialTransmittedPowerdBm,
final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(initialPosition, initialTransmittedPowerdBm, listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param listener listener in charge of attending events raised by this instance.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Point3D initialPosition,
final Double initialTransmittedPowerdBm, final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(readings, initialPosition, initialTransmittedPowerdBm, listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's).
* @param initialPathLossExponent initial path loss exponent. A typical value is 2.0.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Point3D initialPosition,
final Double initialTransmittedPowerdBm, final double initialPathLossExponent) {
super(readings, initialPosition, initialTransmittedPowerdBm, initialPathLossExponent);
}
/**
* Constructor.
*
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param initialPathLossExponent initial path loss exponent. A typical value is 2.0.
*/
public RssiRadioSourceEstimator3D(
final Point3D initialPosition, final Double initialTransmittedPowerdBm,
final double initialPathLossExponent) {
super(initialPosition, initialTransmittedPowerdBm, initialPathLossExponent);
}
/**
* Constructor.
*
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param initialPathLossExponent initial path loss exponent. A typical value is 2.0.
* @param listener listener in charge of attending events raised by this instance.
*/
public RssiRadioSourceEstimator3D(
final Point3D initialPosition, final Double initialTransmittedPowerdBm,
final double initialPathLossExponent, final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(initialPosition, initialTransmittedPowerdBm, initialPathLossExponent, listener);
}
/**
* Constructor.
* Sets radio signal readings belonging to the same radio source.
*
* @param readings radio signal readings belonging to the same
* radio source.
* @param initialPosition initial position to start the estimation of radio
* source position.
* @param initialTransmittedPowerdBm initial transmitted power to start the
* estimation of radio source transmitted power
* (expressed in dBm's)
* @param initialPathLossExponent initial path loss exponent. A typical value is 2.0.
* @param listener listener in charge of attending events raised by this instance.
* @throws IllegalArgumentException if readings are not valid.
*/
public RssiRadioSourceEstimator3D(
final List<? extends RssiReadingLocated<S, Point3D>> readings, final Point3D initialPosition,
final Double initialTransmittedPowerdBm, final double initialPathLossExponent,
final RssiRadioSourceEstimatorListener<S, Point3D> listener) {
super(readings, initialPosition, initialTransmittedPowerdBm, initialPathLossExponent, listener);
}
/**
* Gets minimum required number of readings to estimate
* power, position and path-loss exponent.
* This value depends on the number of parameters to
* be estimated, but for position only, this is 4
* readings for 3D.
*
* @return minimum required number of readings.
*/
@Override
public int getMinReadings() {
var minReadings = 0;
if (isPositionEstimationEnabled()) {
minReadings += Point3D.POINT3D_INHOMOGENEOUS_COORDINATES_LENGTH;
}
if (isTransmittedPowerEstimationEnabled()) {
minReadings++;
}
if (isPathLossEstimationEnabled()) {
minReadings++;
}
return ++minReadings;
}
/**
* Gets number of dimensions of position points.
* This is always 3.
*
* @return number of dimensions of position points.
*/
@Override
public int getNumberOfDimensions() {
return Point3D.POINT3D_INHOMOGENEOUS_COORDINATES_LENGTH;
}
/**
* Gets estimated radio source 3D position.
*
* @return estimated radio source 3D position.
*/
@Override
public Point3D getEstimatedPosition() {
if (estimatedPositionCoordinates == null) {
return null;
}
final var result = new InhomogeneousPoint3D();
getEstimatedPosition(result);
return result;
}
/**
* Gets estimated located radio source with estimated transmitted power.
*
* @return estimated located radio source with estimated transmitted power or null.
*/
@Override
@SuppressWarnings({"unchecked", "DuplicatedCode"})
public RadioSourceWithPowerAndLocated<Point3D> getEstimatedRadioSource() {
final var readings = getReadings();
if (readings == null || readings.isEmpty()) {
return null;
}
final var source = readings.get(0).getSource();
final var estimatedPosition = getEstimatedPosition();
if (estimatedPosition == null) {
return null;
}
final var estimatedPositionCovariance = getEstimatedPositionCovariance();
final var transmittedPowerVariance = getEstimatedTransmittedPowerVariance();
final var transmittedPowerStandardDeviation = transmittedPowerVariance != null
? Math.sqrt(transmittedPowerVariance) : null;
final var pathlossExponentVariance = getEstimatedPathLossExponentVariance();
final var pathlossExponentStandardDeviation = pathlossExponentVariance != null
? Math.sqrt(pathlossExponentVariance) : null;
if (source instanceof WifiAccessPoint accessPoint) {
return new WifiAccessPointWithPowerAndLocated3D(accessPoint.getBssid(), accessPoint.getFrequency(),
accessPoint.getSsid(), getEstimatedTransmittedPowerdBm(), transmittedPowerStandardDeviation,
getEstimatedPathLossExponent(), pathlossExponentStandardDeviation, estimatedPosition,
estimatedPositionCovariance);
} else if (source instanceof Beacon beacon) {
return new BeaconWithPowerAndLocated3D(beacon.getIdentifiers(), getEstimatedTransmittedPowerdBm(),
beacon.getFrequency(), beacon.getBluetoothAddress(), beacon.getBeaconTypeCode(),
beacon.getManufacturer(), beacon.getServiceUuid(), beacon.getBluetoothName(),
getEstimatedPathLossExponent(), transmittedPowerStandardDeviation,
pathlossExponentStandardDeviation, estimatedPosition, estimatedPositionCovariance);
} else {
return null;
}
}
}