diff --git a/src/algorithms/PVT/adapters/rtklib_pvt.cc b/src/algorithms/PVT/adapters/rtklib_pvt.cc
index 74b2f4c5d..c5532dea2 100644
--- a/src/algorithms/PVT/adapters/rtklib_pvt.cc
+++ b/src/algorithms/PVT/adapters/rtklib_pvt.cc
@@ -48,6 +48,12 @@ namespace bc = boost::integer;
 
 using google::LogMessage;
 
+
+void RtklibPvt::clear_ephemeris()
+{
+    pvt_->clear_ephemeris();
+}
+
 RtklibPvt::RtklibPvt(ConfigurationInterface* configuration,
     std::string role,
     unsigned int in_streams,
@@ -515,6 +521,22 @@ RtklibPvt::~RtklibPvt()
     rtkfree(&rtk);
 }
 
+std::map<int, Gps_Ephemeris> RtklibPvt::get_gps_ephemeris()
+{
+    return pvt_->get_gps_ephemeris_map();
+}
+std::map<int, Galileo_Ephemeris> RtklibPvt::get_galileo_ephemeris()
+{
+    return pvt_->get_galileo_ephemeris_map();
+}
+std::map<int, Gps_Almanac> RtklibPvt::get_gps_almanac()
+{
+    return pvt_->get_gps_almanac_map();
+}
+std::map<int, Galileo_Almanac> RtklibPvt::get_galileo_almanac()
+{
+    return pvt_->get_galileo_almanac_map();
+}
 
 void RtklibPvt::connect(gr::top_block_sptr top_block)
 {
diff --git a/src/algorithms/PVT/adapters/rtklib_pvt.h b/src/algorithms/PVT/adapters/rtklib_pvt.h
index c79519581..75e9c6c6d 100644
--- a/src/algorithms/PVT/adapters/rtklib_pvt.h
+++ b/src/algorithms/PVT/adapters/rtklib_pvt.h
@@ -63,6 +63,13 @@ public:
         return "RTKLIB_PVT";
     }
 
+    void clear_ephemeris();
+    std::map<int, Gps_Ephemeris> get_gps_ephemeris();
+    std::map<int, Galileo_Ephemeris> get_galileo_ephemeris();
+    std::map<int, Gps_Almanac> get_gps_almanac();
+    std::map<int, Galileo_Almanac> get_galileo_almanac();
+
+
     void connect(gr::top_block_sptr top_block) override;
     void disconnect(gr::top_block_sptr top_block) override;
     gr::basic_block_sptr get_left_block() override;
diff --git a/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.cc b/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.cc
index fe2cce6e1..69cc62264 100644
--- a/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.cc
+++ b/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.cc
@@ -234,11 +234,32 @@ void rtklib_pvt_cc::msg_handler_telemetry(pmt::pmt_t msg)
 }
 
 
-std::map<int, Gps_Ephemeris> rtklib_pvt_cc::get_GPS_L1_ephemeris_map()
+std::map<int, Gps_Ephemeris> rtklib_pvt_cc::get_gps_ephemeris_map()
 {
     return d_ls_pvt->gps_ephemeris_map;
 }
 
+std::map<int, Gps_Almanac> rtklib_pvt_cc::get_gps_almanac_map()
+{
+    return d_ls_pvt->gps_almanac_map;
+}
+
+std::map<int, Galileo_Ephemeris> rtklib_pvt_cc::get_galileo_ephemeris_map()
+{
+    return d_ls_pvt->galileo_ephemeris_map;
+}
+std::map<int, Galileo_Almanac> rtklib_pvt_cc::get_galileo_almanac_map()
+{
+    return d_ls_pvt->galileo_almanac_map;
+}
+
+void rtklib_pvt_cc::clear_ephemeris()
+{
+    d_ls_pvt->gps_ephemeris_map.clear();
+    d_ls_pvt->gps_almanac_map.clear();
+    d_ls_pvt->galileo_ephemeris_map.clear();
+    d_ls_pvt->galileo_almanac_map.clear();
+}
 
 rtklib_pvt_cc::rtklib_pvt_cc(uint32_t nchannels,
     const Pvt_Conf& conf_,
diff --git a/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.h b/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.h
index 427936704..f063431d1 100644
--- a/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.h
+++ b/src/algorithms/PVT/gnuradio_blocks/rtklib_pvt_cc.h
@@ -31,7 +31,7 @@
 #ifndef GNSS_SDR_RTKLIB_PVT_CC_H
 #define GNSS_SDR_RTKLIB_PVT_CC_H
 
-
+#include "gps_ephemeris.h"
 #include "nmea_printer.h"
 #include "kml_printer.h"
 #include "gpx_printer.h"
@@ -142,11 +142,22 @@ public:
         rtk_t& rtk);
 
     /*!
-     * \brief Get latest set of GPS L1 ephemeris from PVT block
+     * \brief Get latest set of ephemeris from PVT block
      *
-     * It is used to save the assistance data at the receiver shutdown
      */
-    std::map<int, Gps_Ephemeris> get_GPS_L1_ephemeris_map();
+    std::map<int, Gps_Ephemeris> get_gps_ephemeris_map();
+
+    std::map<int, Gps_Almanac> get_gps_almanac_map();
+
+    std::map<int, Galileo_Ephemeris> get_galileo_ephemeris_map();
+
+    std::map<int, Galileo_Almanac> get_galileo_almanac_map();
+
+    /*!
+     * \brief Clear all ephemeris information and the almanacs for GPS and Galileo
+     *
+     */
+    void clear_ephemeris();
 
     ~rtklib_pvt_cc();  //!< Default destructor
 
diff --git a/src/algorithms/channel/libs/channel_fsm.cc b/src/algorithms/channel/libs/channel_fsm.cc
index 5b212193a..14a4e6b12 100644
--- a/src/algorithms/channel/libs/channel_fsm.cc
+++ b/src/algorithms/channel/libs/channel_fsm.cc
@@ -59,7 +59,6 @@ bool ChannelFsm::Event_stop_channel()
     switch (d_state)
         {
         case 0:  //already in stanby
-            return true;
             break;
         case 1:  //acquisition
             d_state = 0;
@@ -70,8 +69,9 @@ bool ChannelFsm::Event_stop_channel()
             stop_tracking();
             break;
         default:
-            return true;
+            break;
         }
+    return true;
 }
 
 bool ChannelFsm::Event_start_acquisition()
diff --git a/src/algorithms/libs/CMakeLists.txt b/src/algorithms/libs/CMakeLists.txt
index 18dd400b0..ce4560e6f 100644
--- a/src/algorithms/libs/CMakeLists.txt
+++ b/src/algorithms/libs/CMakeLists.txt
@@ -39,6 +39,7 @@ set(GNSS_SPLIBS_SOURCES
         conjugate_sc.cc
         conjugate_ic.cc
         gnss_sdr_create_directory.cc
+        geofunctions.cc
 )
 
 set(GNSS_SPLIBS_HEADERS
diff --git a/src/tests/system-tests/libs/geofunctions.cc b/src/algorithms/libs/geofunctions.cc
similarity index 100%
rename from src/tests/system-tests/libs/geofunctions.cc
rename to src/algorithms/libs/geofunctions.cc
diff --git a/src/tests/system-tests/libs/geofunctions.h b/src/algorithms/libs/geofunctions.h
similarity index 100%
rename from src/tests/system-tests/libs/geofunctions.h
rename to src/algorithms/libs/geofunctions.h
diff --git a/src/algorithms/libs/rtklib/rtklib_conversions.cc b/src/algorithms/libs/rtklib/rtklib_conversions.cc
index 7953509a2..22b8af3b9 100644
--- a/src/algorithms/libs/rtklib/rtklib_conversions.cc
+++ b/src/algorithms/libs/rtklib/rtklib_conversions.cc
@@ -116,7 +116,7 @@ geph_t eph_to_rtklib(const Glonass_Gnav_Ephemeris& glonass_gnav_eph, const Glona
 eph_t eph_to_rtklib(const Galileo_Ephemeris& gal_eph)
 {
     eph_t rtklib_sat = {0, 0, 0, 0, 0, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0.0, 0.0, 0.0, 0.0, 0.0,
-        0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {}, {}, 0.0, 0.0 };
+        0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {}, {}, 0.0, 0.0};
     //Galileo is the third satellite system for RTKLIB, so, add the required offset to discriminate Galileo ephemeris
     rtklib_sat.sat = gal_eph.i_satellite_PRN + NSATGPS + NSATGLO;
     rtklib_sat.A = gal_eph.A_1 * gal_eph.A_1;
@@ -174,7 +174,7 @@ eph_t eph_to_rtklib(const Galileo_Ephemeris& gal_eph)
 eph_t eph_to_rtklib(const Gps_Ephemeris& gps_eph)
 {
     eph_t rtklib_sat = {0, 0, 0, 0, 0, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0.0, 0.0, 0.0, 0.0, 0.0,
-        0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {}, {}, 0.0, 0.0 };
+        0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {}, {}, 0.0, 0.0};
     rtklib_sat.sat = gps_eph.i_satellite_PRN;
     rtklib_sat.A = gps_eph.d_sqrt_A * gps_eph.d_sqrt_A;
     rtklib_sat.M0 = gps_eph.d_M_0;
@@ -231,7 +231,7 @@ eph_t eph_to_rtklib(const Gps_Ephemeris& gps_eph)
 eph_t eph_to_rtklib(const Gps_CNAV_Ephemeris& gps_cnav_eph)
 {
     eph_t rtklib_sat = {0, 0, 0, 0, 0, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0.0, 0.0, 0.0, 0.0, 0.0,
-        0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {}, {}, 0.0, 0.0 };
+        0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, {}, {}, 0.0, 0.0};
     rtklib_sat.sat = gps_cnav_eph.i_satellite_PRN;
     const double A_REF = 26559710.0;  // See IS-GPS-200H,  pp. 170
     rtklib_sat.A = A_REF + gps_cnav_eph.d_DELTA_A;
@@ -291,3 +291,55 @@ eph_t eph_to_rtklib(const Gps_CNAV_Ephemeris& gps_cnav_eph)
 
     return rtklib_sat;
 }
+
+alm_t alm_to_rtklib(const Gps_Almanac& gps_alm)
+{
+    alm_t rtklib_alm;
+
+    rtklib_alm = {0, 0, 0, 0, {0, 0}, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+
+    rtklib_alm.sat = gps_alm.i_satellite_PRN;
+    rtklib_alm.svh = gps_alm.i_SV_health;
+    rtklib_alm.svconf = gps_alm.i_AS_status;
+    rtklib_alm.week = gps_alm.i_WNa;
+    rtklib_alm.toa = gpst2time(gps_alm.i_WNa, gps_alm.d_Toa);
+    rtklib_alm.A = gps_alm.d_sqrt_A * gps_alm.d_sqrt_A;
+    rtklib_alm.e = gps_alm.d_e_eccentricity;
+    rtklib_alm.i0 = gps_alm.d_Delta_i + 0.3;
+    rtklib_alm.OMG0 = gps_alm.d_OMEGA0;
+    rtklib_alm.OMGd = gps_alm.d_OMEGA_DOT;
+    rtklib_alm.omg = gps_alm.d_OMEGA;
+    rtklib_alm.M0 = gps_alm.d_M_0;
+    rtklib_alm.f0 = gps_alm.d_A_f0;
+    rtklib_alm.f1 = gps_alm.d_A_f1;
+    rtklib_alm.toas = gps_alm.d_Toa;
+
+
+    return rtklib_alm;
+}
+alm_t alm_to_rtklib(const Galileo_Almanac& gal_alm)
+{
+    alm_t rtklib_alm;
+
+    rtklib_alm = {0, 0, 0, 0, {0, 0}, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+
+    rtklib_alm.sat = gal_alm.i_satellite_PRN;
+    rtklib_alm.svh = gal_alm.E1B_HS;
+    rtklib_alm.svconf = gal_alm.E1B_HS;
+    rtklib_alm.week = gal_alm.d_WNa;
+    rtklib_alm.toa = gpst2time(gal_alm.d_WNa, gal_alm.d_Toa);
+    rtklib_alm.A = 5440.588203494 + gal_alm.d_Delta_sqrt_A;
+    rtklib_alm.A = rtklib_alm.A * rtklib_alm.A;
+    rtklib_alm.e = gal_alm.d_e_eccentricity;
+    rtklib_alm.i0 = gal_alm.d_Delta_i + 0.31111;
+    rtklib_alm.OMG0 = gal_alm.d_OMEGA0;
+    rtklib_alm.OMGd = gal_alm.d_OMEGA_DOT;
+    rtklib_alm.omg = gal_alm.d_OMEGA;
+    rtklib_alm.M0 = gal_alm.d_M_0;
+    rtklib_alm.f0 = gal_alm.d_A_f0;
+    rtklib_alm.f1 = gal_alm.d_A_f1;
+    rtklib_alm.toas = gal_alm.d_Toa;
+
+
+    return rtklib_alm;
+}
diff --git a/src/algorithms/libs/rtklib/rtklib_conversions.h b/src/algorithms/libs/rtklib/rtklib_conversions.h
index 11f4208d1..dca5ec7be 100644
--- a/src/algorithms/libs/rtklib/rtklib_conversions.h
+++ b/src/algorithms/libs/rtklib/rtklib_conversions.h
@@ -38,10 +38,16 @@
 #include "gps_cnav_ephemeris.h"
 #include "glonass_gnav_ephemeris.h"
 #include "glonass_gnav_utc_model.h"
+#include "gps_almanac.h"
+#include "galileo_almanac.h"
 
 eph_t eph_to_rtklib(const Galileo_Ephemeris& gal_eph);
 eph_t eph_to_rtklib(const Gps_Ephemeris& gps_eph);
 eph_t eph_to_rtklib(const Gps_CNAV_Ephemeris& gps_cnav_eph);
+
+alm_t alm_to_rtklib(const Gps_Almanac& gps_alm);
+alm_t alm_to_rtklib(const Galileo_Almanac& gal_alm);
+
 /*!
  * \brief Transforms a Glonass_Gnav_Ephemeris to its RTKLIB counterpart
  * \param glonass_gnav_eph GLONASS GNAV Ephemeris structure
diff --git a/src/core/interfaces/pvt_interface.h b/src/core/interfaces/pvt_interface.h
index 69b23f541..c9a2db162 100644
--- a/src/core/interfaces/pvt_interface.h
+++ b/src/core/interfaces/pvt_interface.h
@@ -38,6 +38,10 @@
 #define GNSS_SDR_PVT_INTERFACE_H_
 
 #include "gnss_block_interface.h"
+#include "gps_ephemeris.h"
+#include "galileo_ephemeris.h"
+#include "gps_almanac.h"
+#include "galileo_almanac.h"
 
 /*!
  * \brief This class represents an interface to a PVT block.
@@ -52,6 +56,11 @@ class PvtInterface : public GNSSBlockInterface
 {
 public:
     virtual void reset() = 0;
+    virtual void clear_ephemeris() = 0;
+    virtual std::map<int, Gps_Ephemeris> get_gps_ephemeris() = 0;
+    virtual std::map<int, Galileo_Ephemeris> get_galileo_ephemeris() = 0;
+    virtual std::map<int, Gps_Almanac> get_gps_almanac() = 0;
+    virtual std::map<int, Galileo_Almanac> get_galileo_almanac() = 0;
 };
 
 #endif /* GNSS_SDR_PVT_INTERFACE_H_ */
diff --git a/src/core/receiver/control_thread.cc b/src/core/receiver/control_thread.cc
index a73d2b446..c95973797 100644
--- a/src/core/receiver/control_thread.cc
+++ b/src/core/receiver/control_thread.cc
@@ -35,6 +35,7 @@
 #include "control_thread.h"
 #include "concurrent_queue.h"
 #include "concurrent_map.h"
+#include "pvt_interface.h"
 #include "control_message_factory.h"
 #include "file_configuration.h"
 #include "gnss_flowgraph.h"
@@ -49,6 +50,10 @@
 #include "gps_almanac.h"
 #include "glonass_gnav_ephemeris.h"
 #include "glonass_gnav_utc_model.h"
+#include "geofunctions.h"
+#include "rtklib_rtkcmn.h"
+#include "rtklib_conversions.h"
+#include "rtklib_ephemeris.h"
 #include <boost/lexical_cast.hpp>
 #include <boost/chrono.hpp>
 #include <glog/logging.h>
@@ -693,6 +698,10 @@ void ControlThread::process_control_messages()
                 }
             else
                 {
+                    if (control_messages_->at(i)->who == 300)  //some TC commands require also actions from controlthread
+                        {
+                            apply_action(control_messages_->at(i)->what);
+                        }
                     flowgraph_->apply_action(control_messages_->at(i)->who, control_messages_->at(i)->what);
                 }
             processed_control_messages_++;
@@ -704,6 +713,8 @@ void ControlThread::process_control_messages()
 
 void ControlThread::apply_action(unsigned int what)
 {
+    std::shared_ptr<PvtInterface> pvt_ptr;
+    std::vector<std::pair<int, Gnss_Satellite>> visible_satellites;
     switch (what)
         {
         case 0:
@@ -717,12 +728,148 @@ void ControlThread::apply_action(unsigned int what)
             restart_ = true;
             applied_actions_++;
             break;
+        case 12:
+            DLOG(INFO) << "Receiver action HOTSTART";
+            visible_satellites = get_visible_sats(cmd_interface_.get_utc_time(), cmd_interface_.get_LLH());
+            //reorder the satellite queue to acquire first those visible satellites
+            flowgraph_->priorize_satellites(visible_satellites);
+            //start again the satellite acquisitions (done in chained applyaction to flowgraph)
+            break;
+        case 13:
+            DLOG(INFO) << "Receiver action WARMSTART";
+            //delete all ephemeris and almanac information from maps (also the PVT map queue)
+            pvt_ptr = flowgraph_->get_pvt();
+            pvt_ptr->clear_ephemeris();
+            //load the ephemeris and the almanac from XML files (receiver assistance)
+            read_assistance_from_XML();
+            //call here the function that computes the set of visible satellites and its elevation
+            //for the date and time specified by the warmstart command and the assisted position
+            get_visible_sats(cmd_interface_.get_utc_time(), cmd_interface_.get_LLH());
+            //reorder the satellite queue to acquire first those visible satellites
+            flowgraph_->priorize_satellites(visible_satellites);
+            //start again the satellite acquisitions (done in chained applyaction to flowgraph)
+            break;
         default:
             DLOG(INFO) << "Unrecognized action.";
             break;
         }
 }
 
+std::vector<std::pair<int, Gnss_Satellite>> ControlThread::get_visible_sats(time_t rx_utc_time, arma::vec LLH)
+{
+    //1. Compute rx ECEF position from LLH WGS84
+    arma::vec LLH_rad = arma::vec{degtorad(LLH(0)), degtorad(LLH(1)), LLH(2)};
+    arma::mat C_tmp = arma::zeros(3, 3);
+    arma::vec r_eb_e = arma::zeros(3, 1);
+    arma::vec v_eb_e = arma::zeros(3, 1);
+    Geo_to_ECEF(LLH_rad, arma::vec{0, 0, 0}, C_tmp, r_eb_e, v_eb_e, C_tmp);
+
+    //2. Compute rx GPS time from UTC time
+    gtime_t utc_gtime;
+    utc_gtime.time = rx_utc_time;
+    utc_gtime.sec = 0;
+    gtime_t gps_gtime = utc2gpst(utc_gtime);
+
+    //2. loop throught all the available ephemeris or almanac and compute satellite positions and elevations
+    // store visible satellites in a vector of pairs <int,Gnss_Satellite> to associate an elevation to the each satellite
+    std::vector<std::pair<int, Gnss_Satellite>> available_satellites;
+
+    std::shared_ptr<PvtInterface> pvt_ptr = flowgraph_->get_pvt();
+
+    std::map<int, Gps_Ephemeris> gps_eph_map = pvt_ptr->get_gps_ephemeris();
+    for (std::map<int, Gps_Ephemeris>::iterator it = gps_eph_map.begin(); it != gps_eph_map.end(); ++it)
+        {
+            eph_t rtklib_eph = eph_to_rtklib(it->second);
+            double r_sat[3];
+            double clock_bias_s;
+            double sat_pos_variance_m2;
+            eph2pos(gps_gtime, &rtklib_eph, &r_sat[0], &clock_bias_s,
+                &sat_pos_variance_m2);
+            double Az, El, dist_m;
+            arma::vec r_sat_eb_e = arma::vec{r_sat[0], r_sat[1], r_sat[2]};
+            arma::vec dx = r_sat_eb_e - r_eb_e;
+            topocent(&Az, &El, &dist_m, r_eb_e, dx);
+            std::cout << "Using GPS Ephemeris: Sat " << it->second.i_satellite_PRN << " Az: " << Az << " El: " << El << std::endl;
+            //push sat
+            if (El > 0)
+                {
+                    available_satellites.push_back(std::pair<int, Gnss_Satellite>(floor(El),
+                        (Gnss_Satellite(std::string("GPS"), it->second.i_satellite_PRN))));
+                }
+        }
+
+    std::map<int, Galileo_Ephemeris> gal_eph_map = pvt_ptr->get_galileo_ephemeris();
+    for (std::map<int, Galileo_Ephemeris>::iterator it = gal_eph_map.begin(); it != gal_eph_map.end(); ++it)
+        {
+            eph_t rtklib_eph = eph_to_rtklib(it->second);
+            double r_sat[3];
+            double clock_bias_s;
+            double sat_pos_variance_m2;
+            eph2pos(gps_gtime, &rtklib_eph, &r_sat[0], &clock_bias_s,
+                &sat_pos_variance_m2);
+            double Az, El, dist_m;
+            arma::vec r_sat_eb_e = arma::vec{r_sat[0], r_sat[1], r_sat[2]};
+            arma::vec dx = r_sat_eb_e - r_eb_e;
+            topocent(&Az, &El, &dist_m, r_eb_e, dx);
+            std::cout << "Using Galileo Ephemeris: Sat " << it->second.i_satellite_PRN << " Az: " << Az << " El: " << El << std::endl;
+            //push sat
+            if (El > 0)
+                {
+                    available_satellites.push_back(std::pair<int, Gnss_Satellite>(floor(El),
+                        (Gnss_Satellite(std::string("Galileo"), it->second.i_satellite_PRN))));
+                }
+        }
+
+    std::map<int, Gps_Almanac> gps_alm_map = pvt_ptr->get_gps_almanac();
+    for (std::map<int, Gps_Almanac>::iterator it = gps_alm_map.begin(); it != gps_alm_map.end(); ++it)
+        {
+            alm_t rtklib_alm = alm_to_rtklib(it->second);
+            double r_sat[3];
+            double clock_bias_s;
+            double sat_pos_variance_m2;
+            alm2pos(gps_gtime, &rtklib_alm, &r_sat[0], &clock_bias_s);
+            double Az, El, dist_m;
+            arma::vec r_sat_eb_e = arma::vec{r_sat[0], r_sat[1], r_sat[2]};
+            arma::vec dx = r_sat_eb_e - r_eb_e;
+            topocent(&Az, &El, &dist_m, r_eb_e, dx);
+            std::cout << "Using GPS Almanac:  Sat " << it->second.i_satellite_PRN << " Az: " << Az << " El: " << El << std::endl;
+            //push sat
+            if (El > 0)
+                {
+                    available_satellites.push_back(std::pair<int, Gnss_Satellite>(floor(El),
+                        (Gnss_Satellite(std::string("GPS"), it->second.i_satellite_PRN))));
+                }
+        }
+
+    std::map<int, Galileo_Almanac> gal_alm_map = pvt_ptr->get_galileo_almanac();
+    for (std::map<int, Galileo_Almanac>::iterator it = gal_alm_map.begin(); it != gal_alm_map.end(); ++it)
+        {
+            alm_t rtklib_alm = alm_to_rtklib(it->second);
+            double r_sat[3];
+            double clock_bias_s;
+            double sat_pos_variance_m2;
+            alm2pos(gps_gtime, &rtklib_alm, &r_sat[0], &clock_bias_s);
+            double Az, El, dist_m;
+            arma::vec r_sat_eb_e = arma::vec{r_sat[0], r_sat[1], r_sat[2]};
+            arma::vec dx = r_sat_eb_e - r_eb_e;
+            topocent(&Az, &El, &dist_m, r_eb_e, dx);
+            std::cout << "Using Galileo Almanac:  Sat " << it->second.i_satellite_PRN << " Az: " << Az << " El: " << El << std::endl;
+            //push sat
+            if (El > 0)
+                {
+                    available_satellites.push_back(std::pair<int, Gnss_Satellite>(floor(El),
+                        (Gnss_Satellite(std::string("Galileo"), it->second.i_satellite_PRN))));
+                }
+        }
+
+    //sort the visible satellites in ascending order of elevation
+    std::sort(available_satellites.begin(), available_satellites.end(), [](const std::pair<int, Gnss_Satellite> &a, const std::pair<int, Gnss_Satellite> &b) {  // use lambda. Cleaner and easier to read
+        return a.first < b.first;
+    });
+    //std::reverse(available_satellites.begin(), available_satellites.end());
+    return available_satellites;
+}
+
 
 void ControlThread::gps_acq_assist_data_collector()
 {
diff --git a/src/core/receiver/control_thread.h b/src/core/receiver/control_thread.h
index ffc2ffa39..c62006eee 100644
--- a/src/core/receiver/control_thread.h
+++ b/src/core/receiver/control_thread.h
@@ -35,16 +35,17 @@
 #ifndef GNSS_SDR_CONTROL_THREAD_H_
 #define GNSS_SDR_CONTROL_THREAD_H_
 
+#include "gnss_satellite.h"
 #include "control_message_factory.h"
 #include "gnss_sdr_supl_client.h"
 #include "tcp_cmd_interface.h"
+#include "gnss_flowgraph.h"
+#include "configuration_interface.h"
 #include <boost/thread.hpp>
 #include <gnuradio/msg_queue.h>
 #include <memory>
 #include <vector>
-
-class GNSSFlowgraph;
-class ConfigurationInterface;
+#include <armadillo>
 
 
 /*!
@@ -143,6 +144,12 @@ private:
      */
     void gps_acq_assist_data_collector();
 
+    /*
+     * Compute elevations for the specified time and position for all the available satellites in ephemeris and almanac queues
+     * returns a vector filled with the available satellites ordered from high elevation to low elevation angle.
+     */
+
+    std::vector<std::pair<int, Gnss_Satellite>> get_visible_sats(time_t rx_utc_time, arma::vec LLH);
     /*
      * Read initial GNSS assistance from SUPL server or local XML files
      */
diff --git a/src/core/receiver/gnss_flowgraph.cc b/src/core/receiver/gnss_flowgraph.cc
index dbeabf004..527696d00 100644
--- a/src/core/receiver/gnss_flowgraph.cc
+++ b/src/core/receiver/gnss_flowgraph.cc
@@ -1137,10 +1137,6 @@ void GNSSFlowgraph::apply_action(unsigned int who, unsigned int what)
             break;
         case 12:  //request hotstart mode
             LOG(INFO) << "TC request hotstart";
-            //todo: call here the function that computes the set of visible satellites and its elevation
-            //for the date and time specified by the hotstart command and the last available PVT
-            //todo: reorder the satellite queue to acquire first those visible satellites
-            //start again the satellite acquisitions
             for (unsigned int i = 0; i < channels_count_; i++)
                 {
                     unsigned int ch_index = (who + i + 1) % channels_count_;
@@ -1169,12 +1165,6 @@ void GNSSFlowgraph::apply_action(unsigned int who, unsigned int what)
             break;
         case 13:  //request warmstart mode
             LOG(INFO) << "TC request warmstart";
-            //todo: delete all ephemeris and almanac information from maps (also the PVT map queue)
-            //todo: load the ephemeris and the almanac from XML files (receiver assistance)
-            //todo: call here the function that computes the set of visible satellites and its elevation
-            //for the date and time specified by the warmstart command and the assisted position
-            //todo: reorder the satellite queue to acquire first those visible satellites
-
             //start again the satellite acquisitions
             for (unsigned int i = 0; i < channels_count_; i++)
                 {
@@ -1209,6 +1199,60 @@ void GNSSFlowgraph::apply_action(unsigned int who, unsigned int what)
 }
 
 
+void GNSSFlowgraph::priorize_satellites(std::vector<std::pair<int, Gnss_Satellite>> visible_satellites)
+{
+    size_t old_size;
+    Gnss_Signal gs;
+    for (std::vector<std::pair<int, Gnss_Satellite>>::iterator it = visible_satellites.begin(); it != visible_satellites.end(); ++it)
+        {
+            if (it->second.get_system() == "GPS")
+                {
+                    gs = Gnss_Signal(it->second, "1C");
+                    old_size = available_GPS_1C_signals_.size();
+                    available_GPS_1C_signals_.remove(gs);
+                    if (old_size > available_GPS_1C_signals_.size())
+                        {
+                            available_GPS_1C_signals_.push_front(gs);
+                        }
+
+                    gs = Gnss_Signal(it->second, "2S");
+                    old_size = available_GPS_2S_signals_.size();
+                    available_GPS_2S_signals_.remove(gs);
+                    if (old_size > available_GPS_2S_signals_.size())
+                        {
+                            available_GPS_2S_signals_.push_front(gs);
+                        }
+
+                    gs = Gnss_Signal(it->second, "L5");
+                    old_size = available_GPS_L5_signals_.size();
+                    available_GPS_L5_signals_.remove(gs);
+                    if (old_size > available_GPS_L5_signals_.size())
+                        {
+                            available_GPS_L5_signals_.push_front(gs);
+                        }
+                }
+            else if (it->second.get_system() == "Galileo")
+                {
+                    gs = Gnss_Signal(it->second, "1B");
+                    old_size = available_GAL_1B_signals_.size();
+                    available_GAL_1B_signals_.remove(gs);
+                    if (old_size > available_GAL_1B_signals_.size())
+                        {
+                            available_GAL_1B_signals_.push_front(gs);
+                        }
+
+                    gs = Gnss_Signal(it->second, "5X");
+                    old_size = available_GAL_5X_signals_.size();
+                    available_GAL_5X_signals_.remove(gs);
+                    if (old_size > available_GAL_5X_signals_.size())
+                        {
+                            available_GAL_5X_signals_.push_front(gs);
+                        }
+                }
+        }
+}
+
+
 void GNSSFlowgraph::set_configuration(std::shared_ptr<ConfigurationInterface> configuration)
 {
     if (running_)
diff --git a/src/core/receiver/gnss_flowgraph.h b/src/core/receiver/gnss_flowgraph.h
index 1f1d07ada..d5e25543a 100644
--- a/src/core/receiver/gnss_flowgraph.h
+++ b/src/core/receiver/gnss_flowgraph.h
@@ -41,6 +41,11 @@
 #include "gnss_signal.h"
 #include "gnss_sdr_sample_counter.h"
 #include "gnss_synchro_monitor.h"
+#include "gnss_block_interface.h"
+#include "pvt_interface.h"
+#include "channel_interface.h"
+#include "configuration_interface.h"
+#include "gnss_block_factory.h"
 #include <gnuradio/top_block.h>
 #include <gnuradio/msg_queue.h>
 #include <list>
@@ -55,10 +60,6 @@
 #include "gnss_sdr_fpga_sample_counter.h"
 #endif
 
-class GNSSBlockInterface;
-class ChannelInterface;
-class ConfigurationInterface;
-class GNSSBlockFactory;
 
 /*! \brief This class represents a GNSS flow graph.
  *
@@ -129,6 +130,19 @@ public:
      */
     bool send_telemetry_msg(pmt::pmt_t msg);
 
+    /*!
+     * \brief Returns a smart pointer to the PVT object
+     */
+    std::shared_ptr<PvtInterface> get_pvt()
+    {
+        return std::dynamic_pointer_cast<PvtInterface>(pvt_);
+    }
+
+    /*!
+     * \brief Priorize visible satellites in the specified vector
+     */
+    void priorize_satellites(std::vector<std::pair<int, Gnss_Satellite>> visible_satellites);
+
 private:
     void init();  // Populates the SV PRN list available for acquisition and tracking
     void set_signals_list();
diff --git a/src/core/receiver/tcp_cmd_interface.cc b/src/core/receiver/tcp_cmd_interface.cc
index 175d96859..b857ee204 100644
--- a/src/core/receiver/tcp_cmd_interface.cc
+++ b/src/core/receiver/tcp_cmd_interface.cc
@@ -34,6 +34,15 @@
 #include <functional>
 
 
+time_t TcpCmdInterface::get_utc_time()
+{
+    return receiver_utc_time_;
+}
+
+arma::vec TcpCmdInterface::get_LLH()
+{
+    return arma::vec{rx_latitude_, rx_longitude_, rx_altitude_};
+}
 std::string TcpCmdInterface::reset(const std::vector<std::string> &commandLine)
 {
     std::string response;
@@ -78,17 +87,40 @@ std::string TcpCmdInterface::status(const std::vector<std::string> &commandLine)
 std::string TcpCmdInterface::hotstart(const std::vector<std::string> &commandLine)
 {
     std::string response;
-    //todo: read and parse the command line parameter: dd/mm/yyyy HH:MM:SS
-    //todo: store it in a member variable
-    std::unique_ptr<ControlMessageFactory> cmf(new ControlMessageFactory());
-    if (control_queue_ != nullptr)
+    if (commandLine.size() > 5)
         {
-            control_queue_->handle(cmf->GetQueueMessage(300, 12));  //send the standby message (who=300,what=12)
-            response = "OK\n";
+            //read commandline time parameter
+            struct tm tm;
+            strptime(commandLine.at(1).c_str(), "%d/%m/%Y %H:%M:%S", &tm);
+            receiver_utc_time_ = timegm(&tm);
+
+
+            //read latitude, longitude, and height
+            rx_latitude_ = std::stod(commandLine.at(3).c_str());
+            rx_longitude_ = std::stod(commandLine.at(4).c_str());
+            rx_altitude_ = std::stod(commandLine.at(5).c_str());
+
+            if (std::isnan(rx_latitude_) || std::isnan(rx_longitude_) || std::isnan(rx_altitude_))
+                {
+                    response = "ERROR: position malformed\n";
+                }
+            else
+                {
+                    std::unique_ptr<ControlMessageFactory> cmf(new ControlMessageFactory());
+                    if (control_queue_ != nullptr)
+                        {
+                            control_queue_->handle(cmf->GetQueueMessage(300, 12));  //send the standby message (who=300,what=12)
+                            response = "OK\n";
+                        }
+                    else
+                        {
+                            response = "ERROR\n";
+                        }
+                }
         }
     else
         {
-            response = "ERROR\n";
+            response = "ERROR: time parameter not found, please use hotstart %d/%m/%Y %H:%M:%S\n";
         }
     return response;
 }
@@ -96,17 +128,40 @@ std::string TcpCmdInterface::hotstart(const std::vector<std::string> &commandLin
 std::string TcpCmdInterface::warmstart(const std::vector<std::string> &commandLine)
 {
     std::string response;
-    //todo: read and parse the command line parameter: dd/mm/yyyy HH:MM:SS
-    //todo: store it in a member variable
-    std::unique_ptr<ControlMessageFactory> cmf(new ControlMessageFactory());
-    if (control_queue_ != nullptr)
+    if (commandLine.size() > 5)
         {
-            control_queue_->handle(cmf->GetQueueMessage(300, 13));  //send the standby message (who=300,what=13)
-            response = "OK\n";
+            std::string tmp_str;
+            //read commandline time parameter
+            struct tm tm;
+            tmp_str = commandLine.at(1) + commandLine.at(2);
+            strptime(tmp_str.c_str(), "%d/%m/%Y %H:%M:%S", &tm);
+            receiver_utc_time_ = timegm(&tm);
+
+            //read latitude, longitude, and height
+            rx_latitude_ = std::stod(commandLine.at(3).c_str());
+            rx_longitude_ = std::stod(commandLine.at(4).c_str());
+            rx_altitude_ = std::stod(commandLine.at(5).c_str());
+            if (std::isnan(rx_latitude_) || std::isnan(rx_longitude_) || std::isnan(rx_altitude_))
+                {
+                    response = "ERROR: position malformed\n";
+                }
+            else
+                {
+                    std::unique_ptr<ControlMessageFactory> cmf(new ControlMessageFactory());
+                    if (control_queue_ != nullptr)
+                        {
+                            control_queue_->handle(cmf->GetQueueMessage(300, 13));  //send the standby message (who=300,what=13)
+                            response = "OK\n";
+                        }
+                    else
+                        {
+                            response = "ERROR\n";
+                        }
+                }
         }
     else
         {
-            response = "ERROR\n";
+            response = "ERROR: time parameter not found, please use warmstart %d/%m/%Y %H:%M:%S Lat Long H\n";
         }
     return response;
 }
@@ -154,6 +209,10 @@ TcpCmdInterface::TcpCmdInterface()
     register_functions();
     keep_running_ = true;
     control_queue_ = nullptr;
+    rx_latitude_ = 0;
+    rx_longitude_ = 0;
+    rx_altitude_ = 0;
+    receiver_utc_time_ = 0;
 }
 
 
diff --git a/src/core/receiver/tcp_cmd_interface.h b/src/core/receiver/tcp_cmd_interface.h
index 6071e32bd..7da156fe0 100644
--- a/src/core/receiver/tcp_cmd_interface.h
+++ b/src/core/receiver/tcp_cmd_interface.h
@@ -42,7 +42,8 @@
 #include <cstdint>
 #include <gnuradio/message.h>
 #include <gnuradio/msg_queue.h>
-
+#include <armadillo>
+#include "time.h"
 
 class TcpCmdInterface
 {
@@ -51,6 +52,14 @@ public:
     virtual ~TcpCmdInterface();
     void run_cmd_server(int tcp_port);
     void set_msg_queue(gr::msg_queue::sptr control_queue);
+    /*!
+     * \brief gets the UTC time parsed from the last TC command issued
+     */
+    time_t get_utc_time();
+    /*!
+     * \brief gets the Latitude, Longitude and Altitude vector from the last TC command issued
+     */
+    arma::vec get_LLH();
 
 
 private:
@@ -68,6 +77,12 @@ private:
 
     gr::msg_queue::sptr control_queue_;
     bool keep_running_;
+
+    time_t receiver_utc_time_;
+
+    double rx_latitude_;
+    double rx_longitude_;
+    double rx_altitude_;
 };
 
 #endif /* GNSS_SDR_TCPCMDINTERFACE_H_ */
diff --git a/src/main/CMakeLists.txt b/src/main/CMakeLists.txt
index 7b41ccfbd..701f8ca95 100644
--- a/src/main/CMakeLists.txt
+++ b/src/main/CMakeLists.txt
@@ -50,6 +50,7 @@ include_directories(
      ${CMAKE_SOURCE_DIR}/src/core/system_parameters
      ${CMAKE_SOURCE_DIR}/src/core/interfaces
      ${CMAKE_SOURCE_DIR}/src/core/receiver
+     ${CMAKE_SOURCE_DIR}/src/core/monitor
      ${CMAKE_SOURCE_DIR}/src/core/libs
      ${CMAKE_SOURCE_DIR}/src/core/libs/supl
      ${CMAKE_SOURCE_DIR}/src/core/libs/supl/asn-rrlp
diff --git a/src/tests/system-tests/libs/CMakeLists.txt b/src/tests/system-tests/libs/CMakeLists.txt
index 4742e80fc..89b6970c3 100644
--- a/src/tests/system-tests/libs/CMakeLists.txt
+++ b/src/tests/system-tests/libs/CMakeLists.txt
@@ -18,7 +18,6 @@
 
 
 set(SYSTEM_TESTING_LIB_SOURCES
-    geofunctions.cc
     spirent_motion_csv_dump_reader.cc
     rtklib_solver_dump_reader.cc
 )