private boolean cellIsValid(OpenCellIdCell cell, int maxMeasurements, int minMeasurements) {
		
		HashSet<Integer> signalValues = new HashSet<Integer>();
		for(Measurement m : cell.getMeasurements()) {
			signalValues.add(m.getSignalStrength());
		}
		if(signalValues.size() <= 3)
			return false;
		
		if(cell.getMeasurements().size() > maxMeasurements)
			return false;
		else if(cell.getMeasurements().size() < minMeasurements)
			return false;
		
		return true;
	}