diff --git a/utils/bin/osmo-gsm-tester_zmq_broker.py b/utils/bin/osmo-gsm-tester_zmq_broker.py
new file mode 100755
index 0000000..3681e7e
--- /dev/null
+++ b/utils/bin/osmo-gsm-tester_zmq_broker.py
@@ -0,0 +1,190 @@
+#!/usr/bin/env python2
+
+from distutils.version import StrictVersion
+
+from gnuradio.fft import window
+from gnuradio import blocks
+from gnuradio import gr
+from gnuradio.filter import firdes
+import sys
+import json
+from argparse import ArgumentParser
+from gnuradio.eng_arg import eng_float, intx
+from gnuradio import eng_notation
+from gnuradio import zeromq
+import socket
+import argparse
+from signal import *
+
+class GrBroker(gr.top_block):
+
+    def __init__(self, args, cfg):
+        gr.top_block.__init__(self, "Intra Handover Flowgraph")
+
+        ##################################################
+        # Variables
+        ##################################################
+        self.args = args
+        self.cfg = cfg
+        self.samp_rate = samp_rate = 23040000
+        self.relative_gain = relative_gain = 1.0
+        self.blocks_add = {}
+
+        ##################################################
+        # Blocks
+        ##################################################
+
+        # Build ENB side + connect to per stream multilier:
+        for enb in self.cfg['enb']:
+            for it in enb:
+                source_addr = 'tcp://%s:%u' % (it['peer_addr'].encode('utf-8'), it['peer_port'])
+                sink_addr = 'tcp://%s:%u' % (args.bind_addr, it['bind_port'])
+                print('enb: earfcn=%u source=%r sink=%r' % (it['earfcn'], source_addr, sink_addr))
+                it['gr_block_zmq_source'] = zeromq.req_source(gr.sizeof_gr_complex, 1, source_addr, 100, False, -1)
+                it['gr_block_zmq_sink'] = zeromq.rep_sink(gr.sizeof_gr_complex, 1, sink_addr, 100, False, -1)
+                it['gr_block_multiply'] = blocks.multiply_const_cc(relative_gain)
+                it['gr_block_multiply'].set_block_alias('relative_gain %s' % source_addr)
+                self.connect((it['gr_block_zmq_source'], 0), (it['gr_block_multiply'], 0))
+                if it['use_mimo']:
+                    source_addr = 'tcp://%s:%u' % (it['peer_addr'].encode('utf-8'), it['peer_port'] + 1)
+                    sink_addr = 'tcp://%s:%u' % (args.bind_addr, it['bind_port'] + 1)
+                    print('enb: earfcn=%u source=%r sink=%r (MIMO)' % (it['earfcn'], source_addr, sink_addr))
+                    it['gr_block_zmq_source2'] = zeromq.req_source(gr.sizeof_gr_complex, 1, source_addr, 100, False, -1)
+                    it['gr_block_zmq_sink2'] = zeromq.rep_sink(gr.sizeof_gr_complex, 1, sink_addr, 100, False, -1)
+                    it['gr_block_multiply2'] = blocks.multiply_const_cc(relative_gain)
+                    it['gr_block_multiply2'].set_block_alias('relative_gain %s' % source_addr)
+                    self.connect((it['gr_block_zmq_source2'], 0), (it['gr_block_multiply2'], 0))
+
+        # Build UE side:
+        for ue in self.cfg['ue']:
+            for it in ue:
+                source_addr = 'tcp://%s:%u' % (it['peer_addr'].encode('utf-8'), it['peer_port'])
+                sink_addr = 'tcp://%s:%u' % (args.bind_addr, it['bind_port'])
+                print('ue: earfcn=%u source=%r sink=%r' % (it['earfcn'], source_addr, sink_addr))
+                it['gr_block_zmq_source'] = zeromq.req_source(gr.sizeof_gr_complex, 1, source_addr, 100, False, -1)
+                it['gr_block_zmq_sink'] = zeromq.rep_sink(gr.sizeof_gr_complex, 1, sink_addr, 100, False, -1)
+                if it['use_mimo']:
+                    source_addr = 'tcp://%s:%u' % (it['peer_addr'].encode('utf-8'), it['peer_port'] + 1)
+                    sink_addr = 'tcp://%s:%u' % (args.bind_addr, it['bind_port'] + 1)
+                    print('ue: earfcn=%u source=%r sink=%r (MIMO)' % (it['earfcn'], source_addr, sink_addr))
+                    it['gr_block_zmq_source2'] = zeromq.req_source(gr.sizeof_gr_complex, 1, source_addr, 100, False, -1)
+                    it['gr_block_zmq_sink2'] = zeromq.rep_sink(gr.sizeof_gr_complex, 1, sink_addr, 100, False, -1)
+
+        # Create per EARFCN adder (only 2->1 supported so far)
+        earfcn_li = self.calc_earfcn_list()
+        blocks_add_next_avail_port = {}
+        for earfcn in earfcn_li:
+                self.blocks_add[earfcn] = blocks.add_vcc(1)
+                blocks_add_next_avail_port[earfcn] = 0
+        # Connect the ENB-side multipliers to the Adder input ports:
+        idx = 0
+        for enb in self.cfg['enb']:
+            for it in enb:
+                print('Connecting ENB port %u to Adder[%u] for earfcn %u' % (it['bind_port'], blocks_add_next_avail_port[earfcn], it['earfcn']))
+                self.connect((it['gr_block_multiply'], 0), (self.blocks_add[it['earfcn']], blocks_add_next_avail_port[earfcn]))
+                # TODO: if it['use_mimo'], connect it['gr_block_multiply2'] to some adder...
+                blocks_add_next_avail_port[earfcn] += 1
+
+        # Connect the Adder to the UE-side (Dl):
+        for earfcn, bl_add in self.blocks_add.items():
+            for ue in self.cfg['ue']:
+                for it in ue:
+                    if it['earfcn'] != earfcn:
+                        continue
+                    print('Connecting Adder for earfcn %u to UE port %u' % (earfcn, it['bind_port']))
+                    self.connect((bl_add, 0), (it['gr_block_zmq_sink'], 0))
+                    # TODO: if it['use_mimo'], connect some adder to it['gr_block_zmq_sink2']...
+
+        # UL: Connect 1 UE port splitting it into N ENB ports:
+        for ue in self.cfg['ue']:
+            for it_ue in ue:
+                for enb in self.cfg['enb']:
+                    for it_enb in enb:
+                        if it_ue['earfcn'] != it_enb['earfcn']:
+                            continue
+                        print('connecting UE port %u to ENB port %u, earfcn=%u' % (it_ue['bind_port'], it_enb['bind_port'], it_enb['earfcn']))
+                        self.connect((it_ue['gr_block_zmq_source'], 0), (it_enb['gr_block_zmq_sink'], 0))
+                        if it_ue['use_mimo'] and it_enb['use_mimo']:
+                            self.connect((it_ue['gr_block_zmq_source2'], 0), (it_enb['gr_block_zmq_sink2'], 0))
+
+    def calc_earfcn_list(self):
+        earfcn_li = []
+        for enb in self.cfg['enb']:
+            for it in enb:
+                if it['earfcn'] not in earfcn_li:
+                    earfcn_li.append(it['earfcn'])
+        return earfcn_li
+
+    def set_relative_gain(self, port, relative_gain):
+        for enb in self.cfg['enb']:
+            for it in enb:
+                if it['bind_port'] == port:
+                    print('setting port %u rel_gain to %f' % (port, relative_gain))
+                    it['gr_block_multiply'].set_k(relative_gain)
+                    return
+
+def mainloop(sock, broker):
+    while True:
+        chunk = sock.recv(4096)
+        stringdata = chunk.decode('utf-8')
+        msg = json.loads(stringdata)
+        print('Received msg: %s' % msg)
+
+        if msg['action'] == 'exit':
+            print('Received exit command. Stopping radio...')
+            return
+        elif msg['action'] == 'set_relative_gain':
+            broker.set_relative_gain(msg['port'], msg['rel_gain'])
+        else:
+            print('Unknwon action for message: %s' % msg)
+
+
+def sig_handler_cleanup(signum, frame):
+    print("killed by signal %d" % signum)
+    # This sys.exit() will raise a SystemExit base exception at the current
+    # point of execution. Code must be prepared to clean system-wide resources
+    # by using the "finally" section. This allows at the end 'atexit' hooks to
+    # be called before exiting.
+    sys.exit(1)
+
+def main():
+
+    for sig in (SIGINT, SIGTERM, SIGQUIT, SIGPIPE, SIGHUP):
+        signal(sig, sig_handler_cleanup)
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument('-b', '--bind-addr', dest='bind_addr', help="Address where local sockets are bound to")
+    parser.add_argument('-c', '--ctrl-port', dest='ctrl_port', type=int, default=5005, help="Port where CTRL interface is bound to")
+    args = parser.parse_args()
+
+    print('bind_addr:', repr(args.bind_addr))
+    print('ctrl_port:', repr(args.ctrl_port))
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    sock.bind((args.bind_addr, args.ctrl_port))
+
+    broker = None
+    try:
+        print('waiting for configuration on UDP socket...')
+        chunk = sock.recv(4096)
+        print('Received udp packet')
+        stringdata = chunk.decode('utf-8')
+        cfg = json.loads(stringdata)
+        print('Got config:', stringdata)
+        broker = GrBroker(args, cfg)
+        print('Starting...')
+        broker.start()
+        print('in mainloop')
+        mainloop(sock, broker)
+    except KeyboardInterrupt:
+        pass
+    print('main loop ended, exiting...')
+    # closing flowgraph and socket
+    sock.close()
+    if broker:
+        broker.stop()
+        broker.wait()
+
+
+if __name__ == '__main__':
+    main()
+    print("exit")