FHWS/Indoor
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some fixes [multithreading,..]

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needed interface changes [new options]
logger for android
wifi-ap-optimization
new test-cases
This commit is contained in:
FrankE
2016-09-28 12:19:14 +02:00
parent 91e3367372
commit 4f511d907e
62 changed files with 1418 additions and 175 deletions
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61
sensors/radio/WiFiProbabilityGrid.h
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@@ -6,14 +6,17 @@
#include "../../math/Distributions.h"
#include "../../data/Timestamp.h"
#include "WiFiGridNode.h"
#include "WiFiProbability.h"
#include <unordered_set>
/**
* probability is calculated by comparing pre-calculated wifi-signal-strengths
* attached to each grid-node with a given WiFiMeasurements data structure
*/
class WiFiObserverGrid : public WiFiProbability {
template <typename Node> class WiFiObserverGrid : public WiFiProbability {
private:
@@ -21,14 +24,23 @@ private:
float sigma = 8.0f;
/** additional sigma-per-second (measurement age) to*/
float sigmaPerSecond = 1.5;
float sigmaPerSecond = 3;
std::unordered_set<MACAddress> knownAPs;
public:
/** ctor with uncertainty */
WiFiObserverGrid(const float sigma) : sigma(sigma) {
;
//StaticAssert::AinheritsB<Node, WiFiGridNode>();
for (const AccessPoint& ap : Node::getMapAPs()) {
knownAPs.insert(ap.getMAC());
}
Assert::isFalse(knownAPs.empty(), "no APs known to the grid nodes?!");
}
/**
@@ -36,43 +48,66 @@ public:
* compares the predicted signal-strengths stored on the given node
* with the provided WiFi measurements
*/
template <typename Node> double getProbability(const Node& n, const Timestamp curTime, const WiFiMeasurements& obs) const {
double getProbability(const Node& n, const Timestamp curTime, const WiFiMeasurements& obs) const {
double prob = 0;
// compile-time sanity check. Node must be a subclass off WiFiGridNode
//StaticAssert::AinheritsB<Node, WiFiGridNode>();
double prob = 1;
int numMatchingAPs = 0;
// process each observed measurement
for (const WiFiMeasurement& measurement : obs.entries) {
// if an AP is not known to any of the nodes, just skip it
if (knownAPs.find(measurement.getAP().getMAC()) == knownAPs.end()) {
continue;}
// determine the age for this measurement
const Timestamp age = curTime - measurement.getTimestamp();
// sigma grows with measurement age
const float sigma = this->sigma + this->sigmaPerSecond * age.sec();
float sigma = this->sigma + this->sigmaPerSecond * age.sec();
// the RSSI from the scan
const float measuredRSSI = measurement.getRSSI();
// the RSSI from the model (if available!)
const float modelRSSI = n.getRSSI(measurement.getAP().getMAC());
float modelRSSI = n.getRSSI(measurement.getAP().getMAC());
// no model RSSI available?
if (modelRSSI == 0) {continue;}
// if no model RSSI is available, that means,
// the AP in question is not / only barely visible at this location
// assume a very low signal-strength and increase the sigma
if (modelRSSI == 0) {
modelRSSI = -100;
sigma *= 2;
}
// compare both
const double p = Distribution::Normal<double>::getProbability(measuredRSSI, sigma, modelRSSI);
//const double p = Distribution::Region<double>::getProbability(measuredRSSI, sigma, modelRSSI);
// adjust using log
prob += std::log(p);
//prob += std::log(p);
prob *= p;
++numMatchingAPs;
}
//return std::pow(std::exp(prob), 0.1);
return std::exp(prob);
// sanity check
// Assert::isTrue(numMatchingAPs > 0, "not a single measured AP was matched against known ones. coding error? model error?");
// if (numMatchingAPs == 0) {return 0;}
// as not every node has the same number of visible/matching APs
// we MUST return something like the average probability
return prob;
//return std::pow(prob, 1.0/3.0);
}
/** gnuplot debug dump */
template <typename Node> void dump(Grid<Node>& grid, const Timestamp curTime, const WiFiMeasurements& obs, const std::string& fileName) {
void dump(Grid<Node>& grid, const Timestamp curTime, const WiFiMeasurements& obs, const std::string& fileName) {
std::ofstream out(fileName);
out << "splot '-' with points palette\n";