A Discrete-Event Network Simulator
API
a3-rsrp-handover-algorithm.cc
Go to the documentation of this file.
1 /* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2013 Budiarto Herman
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation;
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  *
18  * Author: Budiarto Herman <budiarto.herman@magister.fi>
19  *
20  */
21 
23 #include <ns3/log.h>
24 #include <ns3/double.h>
25 #include <ns3/lte-common.h>
26 #include <list>
27 
28 namespace ns3 {
29 
30 NS_LOG_COMPONENT_DEFINE ("A3RsrpHandoverAlgorithm");
31 
32 NS_OBJECT_ENSURE_REGISTERED (A3RsrpHandoverAlgorithm);
33 
34 
36  : m_handoverManagementSapUser (0)
37 {
38  NS_LOG_FUNCTION (this);
40 }
41 
42 
44 {
45  NS_LOG_FUNCTION (this);
46 }
47 
48 
49 TypeId
51 {
52  static TypeId tid = TypeId ("ns3::A3RsrpHandoverAlgorithm")
54  .SetGroupName("Lte")
55  .AddConstructor<A3RsrpHandoverAlgorithm> ()
56  .AddAttribute ("Hysteresis",
57  "Handover margin (hysteresis) in dB "
58  "(rounded to the nearest multiple of 0.5 dB)",
59  DoubleValue (3.0),
61  MakeDoubleChecker<uint8_t> (0.0, 15.0)) // Hysteresis IE value range is [0..30] as per Section 6.3.5 of 3GPP TS 36.331
62  .AddAttribute ("TimeToTrigger",
63  "Time during which neighbour cell's RSRP "
64  "must continuously higher than serving cell's RSRP "
65  "in order to trigger a handover",
66  TimeValue (MilliSeconds (256)), // 3GPP time-to-trigger median value as per Section 6.3.5 of 3GPP TS 36.331
68  MakeTimeChecker ())
69  ;
70  return tid;
71 }
72 
73 
74 void
76 {
77  NS_LOG_FUNCTION (this << s);
79 }
80 
81 
84 {
85  NS_LOG_FUNCTION (this);
87 }
88 
89 
90 void
92 {
93  NS_LOG_FUNCTION (this);
94 
96  NS_LOG_LOGIC (this << " requesting Event A3 measurements"
97  << " (hysteresis=" << (uint16_t) hysteresisIeValue << ")"
98  << " (ttt=" << m_timeToTrigger.GetMilliSeconds () << ")");
99 
100  LteRrcSap::ReportConfigEutra reportConfig;
102  reportConfig.a3Offset = 0;
103  reportConfig.hysteresis = hysteresisIeValue;
104  reportConfig.timeToTrigger = m_timeToTrigger.GetMilliSeconds ();
105  reportConfig.reportOnLeave = false;
106  reportConfig.triggerQuantity = LteRrcSap::ReportConfigEutra::RSRP;
107  reportConfig.reportInterval = LteRrcSap::ReportConfigEutra::MS1024;
109 
111 }
112 
113 
114 void
116 {
117  NS_LOG_FUNCTION (this);
119 }
120 
121 
122 void
124  LteRrcSap::MeasResults measResults)
125 {
126  NS_LOG_FUNCTION (this << rnti << (uint16_t) measResults.measId);
127 
128  if (measResults.measId != m_measId)
129  {
130  NS_LOG_WARN ("Ignoring measId " << (uint16_t) measResults.measId);
131  }
132  else
133  {
134  if (measResults.haveMeasResultNeighCells
135  && !measResults.measResultListEutra.empty ())
136  {
137  uint16_t bestNeighbourCellId = 0;
138  uint8_t bestNeighbourRsrp = 0;
139 
140  for (std::list <LteRrcSap::MeasResultEutra>::iterator it = measResults.measResultListEutra.begin ();
141  it != measResults.measResultListEutra.end ();
142  ++it)
143  {
144  if (it->haveRsrpResult)
145  {
146  if ((bestNeighbourRsrp < it->rsrpResult)
147  && IsValidNeighbour (it->physCellId))
148  {
149  bestNeighbourCellId = it->physCellId;
150  bestNeighbourRsrp = it->rsrpResult;
151  }
152  }
153  else
154  {
155  NS_LOG_WARN ("RSRP measurement is missing from cell ID " << it->physCellId);
156  }
157  }
158 
159  if (bestNeighbourCellId > 0)
160  {
161  NS_LOG_LOGIC ("Trigger Handover to cellId " << bestNeighbourCellId);
162  NS_LOG_LOGIC ("target cell RSRP " << (uint16_t) bestNeighbourRsrp);
163  NS_LOG_LOGIC ("serving cell RSRP " << (uint16_t) measResults.rsrpResult);
164 
165  // Inform eNodeB RRC about handover
167  bestNeighbourCellId);
168  }
169  }
170  else
171  {
172  NS_LOG_WARN (this << " Event A3 received without measurement results from neighbouring cells");
173  }
174  } // end of else of if (measResults.measId != m_measId)
175 
176 } // end of DoReportUeMeas
177 
178 
179 bool
181 {
182  NS_LOG_FUNCTION (this << cellId);
183 
190  return true;
191 }
192 
193 
194 } // end of namespace ns3
virtual void DoInitialize(void)
Initialize() implementation.
Definition: object.cc:353
#define NS_LOG_FUNCTION(parameters)
If log level LOG_FUNCTION is enabled, this macro will output all input parameters separated by "...
The abstract base class of a handover algorithm that operates using the Handover Management SAP inter...
double m_hysteresisDb
The Hysteresis attribute.
#define NS_OBJECT_ENSURE_REGISTERED(type)
Register an Object subclass with the TypeId system.
Definition: object-base.h:44
std::list< MeasResultEutra > measResultListEutra
measure result list eutra
Definition: lte-rrc-sap.h:677
Specifies criteria for triggering of an E-UTRA measurement reporting event.
Definition: lte-rrc-sap.h:354
virtual void TriggerHandover(uint16_t rnti, uint16_t targetCellId)=0
Instruct the eNodeB RRC entity to prepare a handover.
#define NS_LOG_COMPONENT_DEFINE(name)
Define a Log component with a specific name.
Definition: log.h:201
Time MilliSeconds(uint64_t value)
Construct a Time in the indicated unit.
Definition: nstime.h:1001
LteHandoverManagementSapProvider * m_handoverManagementSapProvider
Receive API calls from the eNodeB RRC instance.
void DoReportUeMeas(uint16_t rnti, LteRrcSap::MeasResults measResults)
Implementation of LteHandoverManagementSapProvider::ReportUeMeas.
static TypeId GetTypeId()
Get the type ID.
virtual void DoInitialize()
Initialize() implementation.
Ptr< const AttributeChecker > MakeTimeChecker(const Time min, const Time max)
Helper to make a Time checker with bounded range.
Definition: time.cc:446
uint8_t rsrpResult
RSRP result.
Definition: lte-rrc-sap.h:674
AttributeValue implementation for Time.
Definition: nstime.h:1055
bool IsValidNeighbour(uint16_t cellId)
Determines if a neighbour cell is a valid destination for handover.
MeasResults structure.
Definition: lte-rrc-sap.h:671
Time m_timeToTrigger
The TimeToTrigger attribute.
Template for the implementation of the LteHandoverManagementSapProvider as a member of an owner class...
Implementation of the strongest cell handover algorithm, based on RSRP measurements and Event A3...
enum ns3::LteRrcSap::ReportConfigEutra::@65 eventId
Event enumeration.
#define NS_LOG_LOGIC(msg)
Use NS_LOG to output a message of level LOG_LOGIC.
Definition: log.h:285
uint8_t m_measId
The expected measurement identity for A3 measurements.
LteHandoverManagementSapUser * m_handoverManagementSapUser
Interface to the eNodeB RRC instance.
Every class exported by the ns3 library is enclosed in the ns3 namespace.
bool haveMeasResultNeighCells
have measure result neighbor cells
Definition: lte-rrc-sap.h:676
virtual LteHandoverManagementSapProvider * GetLteHandoverManagementSapProvider()
Export the "provider" part of the Handover Management SAP interface.
Ptr< const AttributeAccessor > MakeTimeAccessor(T1 a1)
Create an AttributeAccessor for a class data member, or a lone class get functor or set method...
Definition: nstime.h:1056
Ptr< const AttributeAccessor > MakeDoubleAccessor(T1 a1)
Create an AttributeAccessor for a class data member, or a lone class get functor or set method...
Definition: double.h:42
static uint8_t ActualHysteresis2IeValue(double hysteresisDb)
Returns the IE value of hysteresis.
Definition: lte-common.cc:304
uint8_t measId
measure ID
Definition: lte-rrc-sap.h:673
#define NS_LOG_WARN(msg)
Use NS_LOG to output a message of level LOG_WARN.
Definition: log.h:261
Service Access Point (SAP) offered by the handover algorithm instance to the eNodeB RRC instance...
Reference Signal Received Power.
Definition: lte-rrc-sap.h:399
Event A3: Neighbour becomes amount of offset better than PCell.
Definition: lte-rrc-sap.h:368
virtual uint8_t AddUeMeasReportConfigForHandover(LteRrcSap::ReportConfigEutra reportConfig)=0
Request a certain reporting configuration to be fulfilled by the UEs attached to the eNodeB entity...
A3RsrpHandoverAlgorithm()
Creates a strongest cell handover algorithm instance.
This class can be used to hold variables of floating point type such as 'double' or 'float'...
Definition: double.h:41
virtual void DoDispose()
Destructor implementation.
a unique identifier for an interface.
Definition: type-id.h:58
int64_t GetMilliSeconds(void) const
Get an approximation of the time stored in this instance in the indicated unit.
Definition: nstime.h:345
TypeId SetParent(TypeId tid)
Set the parent TypeId.
Definition: type-id.cc:904
virtual void SetLteHandoverManagementSapUser(LteHandoverManagementSapUser *s)
Set the "user" part of the Handover Management SAP interface that this handover algorithm instance wi...
Service Access Point (SAP) offered by the eNodeB RRC instance to the handover algorithm instance...