14.2 Inter-frequency measurements

25.3313GPPProtocol specificationRadio Resource Control (RRC)Release 17TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

14.2.0a Inter-frequency measurement quantities

The two first measurement quantities listed below are used by the UE to evaluate whether an inter-frequency measurement event has occurred or not, through the computation of a frequency quality estimate. The quantity to use to compute the frequency quality estimate for an inter-frequency measurement is given in the "Inter-frequency measurement quantity" stored for that measurement.

1 Downlink Ec/No (FDD)

2 Downlink received signal code power (RSCP) after despreading.

3 Downlink path loss.

For FDD:

Pathloss in dB = Primary CPICH Tx power – CPICH RSCP.

– For Primary CPICH Tx power the IE "Primary CPICH Tx power" shall be used. The unit is dBm.

– CPICH RSCP is the result of the CPICH RSCP measurement. The unit is dBm.

For TDD:

Pathloss in dB = Primary CCPCH TX power – Primary CCPCH RSCP.

– For Primary CCPCH TX power the IE "Primary CCPCH TX Power" shall be used. The unit is dBm.

– Primary CCPCH RSCP is the result of the Primary CCPCH RSCP measurement. The unit is dBm.

A description of those values can be found in [7] and [8].

14.2.0b Frequency quality estimate

14.2.0b.1 FDD cells

The frequency quality estimate used in events 2a, 2b 2c, 2d, 2e and 2f is defined as:

The variables in the formula are defined as follows ("the virtual active set on frequency j" should be understood as the active set if frequency j is the used frequency or understood as the secondary E-DCH active set if frequency j is the downlink frequency associated with the secondary uplink frequency. If frequency j is a non-used frequency and is not the downlink frequency associated with the secondary uplink frequency, the way the virtual active set is initiated and updated is described in subclause 14.11):

Q_{frequency j} is the estimated quality of the virtual active set on frequency j.

M_{frequency j} is the estimated quality of the virtual active set on frequency j.

M_{i j} is a measurement result of cell i in the virtual active set on frequency j.

N_{A j} is the number of cells in the virtual active set on frequency j.

M_{Best j} is the measurement result of the cell in the virtual active set on frequency j with the highest measurement result.

W_j is a parameter sent from UTRAN to UE and used for frequency j.

If the measurement result is CPICH-Ec/No then M_Frequency, M_{i j} and M_Best are expressed as ratios.

If the measurement result is CPICH-RSCP or PCCPCH-RSCP then M_Frequency, M_{i j} and M_Best are expressed in mW.

14.2.0b.2 TDD cells

Q_{i ,frequency j} is the estimated quality of cell i on frequency j.

M_i is the measurement result for Primary CCPCH RSCP of cell i on the primary frequency expressed in mW.

O_i,j is the cell individual offset of the currently evaluated cell i on frequency j. O_ij is set by IE " Cell individual offset"

14.2.0c Inter-frequency reporting quantities

The quantities that the UE shall report for each cell to UTRAN when the event is triggered for an inter-frequency measurement is given by the "Inter-frequency reporting quantity" IE stored for this measurement and can be the following, from 1 to 8. The quantity number 9 can be reported for each frequency that triggered the report.

1 Cell identity

2 SFN-SFN observed time difference

3 Cell synchronisation information

4 Downlink Ec/No (FDD)

5 Downlink path loss.

For FDD:

Pathloss in dB = Primary CPICH Tx power – CPICH RSCP.

– For Primary CPICH Tx power the IE "Primary CPICH Tx power" shall be used. The unit is dBm.

– CPICH RSCP is the result of the CPICH RSCP measurement. The unit is dBm.

For TDD:

Pathloss in dB = Primary CCPCH TX power – Primary CCPCH RSCP.

– For Primary CCPCH TX power the IE "Primary CCPCH TX Power" shall be used. The unit is dBm.

– Primary CCPCH RSCP is the result of the Primary CCPCH RSCP measurement. The unit is dBm.

If necessary Pathloss shall be rounded up to the next higher integer.
Results higher than 158 shall be reported as 158.
Results lower than 46 shall be reported as 46.

6 Downlink received signal code power (RSCP) after despreading (of a primary CPICH for FDD, and of a primary CCPCH for TDD).

7 ISCP measured on Timeslot basis. (TDD)

8 Proposed TGSN (TDD)

9 UTRA carrier RSSI

A description of those values can be found in [7] and [8].

14.2.1 Inter-frequency reporting events

Within the measurement reporting criteria field in the MEASUREMENT CONTROL message UTRAN notifies the UE which events should trigger the UE to send a MEASUREMENT REPORT message. The listed events are the toolbox from which the UTRAN can choose the reporting events that are needed for the implemented handover evaluation function, or other radio network functions.

All events are evaluated with respect to one of the measurement quantities given in subclause 14.2.0a. The measurement quantities are measured on the monitored primary common pilot channels (CPICH) in FDD mode and the monitored primary common control channels (PCCPCH) in TDD mode of the cell defined in the measurement object. A "non-used frequency" is a frequency that the UE has been ordered to measure upon but is not used for the connection. A "used frequency" is a frequency that the UE has been ordered to measure upon and is also currently used for the connection. An exception to the definition of used and non-used frequency is the frequency of the first secondary serving HS-DSCH cell which shall be treated as a non-used frequency for the purpose of inter-frequency measurement, and when more than one uplink frequency is configured, shall be treated as a used frequency for the purposes of intra-frequency measurement.

If the non-used frequency is the downlink frequency associated with the secondary uplink frequency and if intra-frequency measurement reporting on this frequency is configured, the "monitored set on non-used frequency" consists of cells in the IE "Intra-frequency cell info on secondary UL frequency" in the variable CELL_INFO_LIST that are not part of the secondary E-DCH active set; Otherwise, the "monitored set on non-used frequency" consists of cells in "cells for measurement" (or all cells in CELL_INFO_LIST if "cells for measurement" is not present) in the IE "Inter-frequency cell info" in the variable CELL_INFO_LIST that are not part of the virtual active set on that non-used frequency.

The "detected set on non-used frequency" consists of all cells that are not part of the virtual active set on that non-used frequency and are not in the CELL_INFO_LIST.

The IE "Cells to be excluded in non-used frequency detected cells" notifies the UE to exclude indicated cells from corresponding measurement report and UE shall exclude indicated cells from measurement report for inter-frequency detected set measurement.

If a measurement is configured with IE "Triggering Condition non-used frequency detected cells" the UE maintains 2 virtual active sets and 2 variables (1 variable for event 2g), in order to evaluate the event according to the rules below using one virtual active set and one variable for cells only in the CELL_INFO_LIST, and in parallel using another virtual active set and another variable for all cells (including detected set cells not indicated in "Cells to be excluded in non-used frequency detected cells").

When one inter-frequency measurement identity corresponds to multiple inter-frequency events with identical event identities, the UE behaviour is not specified.

14.2.1.1 Event 2a: Change of best frequency.

When an inter-frequency measurement configuring event 2a is set up, the UE shall:

1> create a variable BEST_FREQUENCY_2A_EVENT per virtual active set related to that measurement, which shall initially contain the used frequency;

1> delete this variable when the measurement is released.

When event 2a is configured in the UE within a measurement, the UE shall:

1> when the measurement is initiated or resumed:

2> store the used frequency in the variable BEST_FREQUENCY_2A_EVENT.

1> if equation 1 below has been fulfilled for a time period indicated by "Time to trigger" while not considering detected set cells for a frequency included for that event and which is not stored in the variable BEST_FREQUENCY_2A_EVENT used for evaluation without detected set cells; or

1> if equation 1 below has been fulfilled for a time period indicated by "Time to trigger" while considering detected set cells but not simultaneously fulfilled for that time while not considering detected set cells, for a frequency included for that event and which is not stored either in the variable BEST_FREQUENCY_2A_EVENT used for evaluation without detected set cells or in the variable BEST_FREQUENCY_2A_EVENT used for evaluation with detected set cells; or

1> if the CSG virtual active set has been updated, since the last measurement report for this event associated with CSG measurement, and equation 1 below has been fulfilled for a time period indicated by "Time to trigger", for a frequency included for that event and which is stored in the variable BEST_FREQUENCY_2A_EVENT:

2> send a measurement report with IEs set as below:

3> set in "inter-frequency measurement event results":

4> "inter-frequency event identity" to "2a"; and

4> "Frequency info" to the frequency that triggered the event; and

4> "Non frequency related measurement event results" to the "Primary CPICH info" of the best primary CPICH for FDD cells in case of non-CSG measurements or "Primary CPICH info" of the cell present in CSG virtual active set in case of CSG measurements or "Primary CCPCH info" to the "Cells parameters ID" of the best primary CCPCH for TDD cells on that frequency, not taking into account the cell individual offset.

4> if the frequency triggered the event due to considering detected set cells:

5> set the IE "Detected Set Trigger".

3> if a non-used frequency triggered the measurement report:

4> include in IE "Inter-frequency measured results list" the measured results for the non-used frequency that triggered the event, not taking into account the cell individual offset.

3> if the used frequency triggered the measurement report:

4> do not include the IE "Inter-frequency measured results list" in the measurement report.

3> set the IE "additional measured results" according to subclause 8.4.2, not taking into account the cell individual offset;

2> update the variable BEST_FREQUENCY_2A_EVENT corresponding to the virtual active set being evaluated with that frequency.

1> if equation 1 below has been fulfilled but the CSG virtual active set is updated for a frequency included for that event:

2> restart evaluation of this event for this frequency.

Equation 1:

The variables in the formula are defined as follows:

Q_{Not Best}is the quality estimate of a frequency not stored the "best frequency" in the variable BEST_FREQUENCY_2A_EVENT.

Q_Best is the quality estimate of the frequency stored in "best frequency" in the variable BEST_FREQUENCY_2A_EVENT.

H_2ais the hysteresis parameter for the event 2a in that measurement.

14.2.1.2 Event 2b: The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold.

When an inter-frequency measurement configuring event 2b is set up, the UE shall:

1> create a variable TRIGGERED_2B_EVENT per virtual active set related to that measurement, which shall initially be empty;

1> delete this variable when the measurement is released.

When event 2b is configured in the UE within a measurement, the UE shall:

1> if equations 1 and 2 below have been fulfilled for a time period indicated by "Time to Trigger" from the same instant, respectively for one or several non-used frequencies included for that event and for the used frequency:

2> if any of those non-used frequency triggered while not considering detected set cells and is not stored in the variable TRIGGERED_2B_EVENT used for evaluation without detected set cells; or

2> if any of those non-used frequency triggered while considering detected set cells but did not simultaneously trigger while not considering detected set cells and is not stored either in the variable TRIGGERED_2B_EVENT used for evaluation without detected set cells or the variable TRIGGERED_2B_EVENT used for evaluation with detected set cells; or

2> if the CSG virtual active set has been updated, since the last measurement report for this event associated with CSG measurement,for any of those non-used frequency which are stored in the variable TRIGGERED_2B_EVENT:

3> store the non-used frequencies that triggered the event and that were not previously stored in the variable TRIGGERED_2B_EVENT corresponding to the virtual active set being evaluated into that variable;

3> send a measurement report with IEs set as below:

4> set in "inter-frequency measurement event results":

5> "inter-frequency event identity" to "2b"; and

5> for each non-used frequency that triggered the event, beginning with the best frequency:

6> "Frequency info" to that non-used frequency; and

6> "Non frequency related measurement event results" to the "Primary CPICH info" of the best primary CPICH for FDD cells in case of non-CSG measurements or "Primary CPICH info" of the cell present in CSG virtual active set in case of CSG measurements or "Primary CCPCH info" to the "Cell parameters ID" of the best primary CCPCH for TDD cells on that non-used frequency, not taking into account the cell individual offset.

6> if the frequency triggered the event due to considering detected set cells:

7> set the IE "Detected Set Trigger".

4> include in IE "Inter-frequency measured results list" the measured results for each non-used frequency that triggered the event, not taking into account the cell individual offset;

4> set the IE "additional measured results" according to subclause 8.4.2, not taking into account the cell individual offset.

1> if this equations 1 and 2 below have been fulfilled but the CSG virtual active set is updated for a frequency included for that event:

2> restart evaluation of this event for this frequency.

1> if equation 3 below is fulfilled for a non-used frequency stored in the variable TRIGGERED_2B_EVENT:

2> remove that non-used frequency from the variable TRIGGERED_2B_EVENT corresponding to the virtual active set being evaluated.

1> if equation 4 below is fulfilled for the used frequency:

2> clear the variable TRIGGERED_2B_EVENT.

Triggering conditions:

Equation 1:

The variables in the formula are defined as follows:

Q_{Non used}is the quality estimate of a non-used frequency that becomes better than an absolute threshold.

T_{Non used 2b} is the absolute threshold that applies for this non-used frequency in that measurement.

H_2b is the hysteresis parameter for the event 2b.

Equation 2:

The variables in the formula are defined as follows:

Q_Usedis the quality estimate of the used frequency.

T_{Used 2b} is the absolute threshold that applies for the used frequency in that measurement.

H_2b is the hysteresis parameter for the event 2b.

Leaving triggered state condition:

Equation 3:

The variables in the formula are defined as follows:

Q_{Non used}is the quality estimate of a non-used frequency that is stored in the variable TRIGGERED_2B_EVENT.

T_{Non used 2b} is the absolute threshold that applies for this non-used frequency in that measurement.

H_2b is the hysteresis parameter for the event 2b.

Equation 4:

The variables in the formula are defined as follows:

Q_Usedis the quality estimate of the used frequency.

T_{Used 2b} is the absolute threshold that applies for the used frequency in that measurement.

H_2b is the hysteresis parameter for the event 2b.

14.2.1.3 Event 2c: The estimated quality of a non-used frequency is above a certain threshold

When an inter-frequency measurement configuring event 2c is set up, the UE shall:

1> create a variable TRIGGERED_2C_EVENT per virtual active set related to that measurement, which shall initially be empty;

1> delete this variable when the measurement is released.

When event 2c is configured in the UE within a measurement, the UE shall:

1> if equation 1 below has been fulfilled for one or several non-used frequencies included for that event during the time "Time to trigger":

2> if any of those non-used frequencies triggered while not considering detected set cells and is not stored in the variable TRIGGERED_2C_EVENT used for evaluation without detected set cells; or

2> if any of those non-used frequency triggered while considering detected set cells but did not simultaneously trigger while not considering detected set cells and is not stored either in the variable TRIGGERED_2C_EVENT used for evaluation without detected set cells or in the variable TRIGGERED_2C_EVENT used for evaluation with detected set cells; or

3> store the non-used frequencies that triggered the event and that were not previously stored in the variable TRIGGERED_2C_EVENT corresponding to the virtual active set being evaluated into that variable;

3> send a measurement report with IEs set as below:

4> set in "inter-frequency measurement event results":

5> "inter-frequency event identity" to "2c"; and

5> for each non-used frequency that triggered the event, beginning with the best frequency:

6> "Frequency info" to that non-used frequency; and

6> if the frequency triggered the event due to considering detected set cells:

7> set the IE "Detected Set Trigger".

4> include in IE "Inter-frequency measured results list" the measured results for each non-used frequency that triggered the event, not taking into account the cell individual offset;

4> set the IE "additional measured results" according to subclause 8.4.2 not taking into account the cell individual offset.

1> if equation 1 below has been fulfilled but the CSG virtual active set is updated for a non-used frequency included for that event:

2> restart evaluation of this event for this frequency.

1> if equation 2 below is fulfilled for a non-used frequency stored in the variable TRIGGERED_2C_EVENT:

2> remove that non-used frequency from the variable TRIGGERED_2C_EVENT corresponding to the virtual active set being evaluated.

Triggering condition:

Equation 1:

The variables in the formula are defined as follows:

Q_{Non used}is the quality estimate of a non-used frequency that becomes better than an absolute threshold.

T_{Non used 2c} is the absolute threshold that applies for this non-used frequency in that measurement.

H_2c is the hysteresis parameter for the event 2c.

Leaving triggered state condition:

Equation 2:

The variables in the formula are defined as follows:

Q_{Non used}is the quality estimate of a non-used frequency stored in the variable TRIGGERED_2C_EVENT.

T_{Non used 2c} is the absolute threshold that applies for this non-used frequency in that measurement.

H_2c is the hysteresis parameter for the event 2c.

14.2.1.4 Event 2d: The estimated quality of the currently used frequency is below a certain threshold

A UE shall be able to perform this measurement and the corresponding event reporting without requiring compressed mode.

When an inter-frequency measurement configuring event 2d is set up, the UE shall:

1> create a variable TRIGGERED_2D_EVENT related to that measurement, which shall initially be set to FALSE;

1> delete this variable when the measurement is released.

When event 2d is configured in the UE within a measurement, the UE shall:

1> if equation 1 below has been fulfilled for the used frequency during the time "Time to trigger":

2> if the variable TRIGGERED_2D_EVENT is set to FALSE:

3> set the variable TRIGGERED_2D_EVENT to TRUE;

3> send a measurement report with IEs set as below:

4> set in "inter-frequency event results": "inter-frequency event identity" to "2d" and no IE "Inter-frequency cells", not taking into account the cell individual offset;

4> include in IE "Inter-frequency measured results list" the measured results for the used frequency, not taking into account the cell individual offset;

4> set the IE "additional measured results" according to subclause 8.4.2, not taking into account the cell individual offset.

1> if the variable TRIGGERED_2D_EVENT is set to TRUE and if equation 2 is fulfilled for the used frequency:

2> set the variable TRIGGERED_2D_EVENT to FALSE.

Triggering condition:

Equation 1:

The variables in the formula are defined as follows:

Q_Usedis the quality estimate of the used frequency.

T_{Used 2d} is the absolute threshold that applies for the used frequency and event 2d.

H_2d is the hysteresis parameter for the event 2d.

Leaving triggered state condition:

Equation 2:

The variables in the formula are defined as follows:

Q_Usedis the quality estimate of the used frequency.

T_{Used 2d} is the absolute threshold that applies for the used frequency and event 2d.

H_2d is the hysteresis parameter for the event 2d.

14.2.1.5 Event 2e: The estimated quality of a non-used frequency is below a certain threshold

When an inter-frequency measurement configuring event 2e is set up, the UE shall:

1> create a variable TRIGGERED_2E_EVENT per virtual active set related to that measurement, which shall initially be empty;

1> delete this variable when the measurement is released.

When event 2e is configured in the UE within a measurement, the UE shall:

1> if equation 1 below has been fulfilled for one or several non-used frequencies included for that event during the time "Time to trigger":

2> if any of those non-used frequencies triggered while not considering detected set cells and is not stored in the variable TRIGGERED_2E_EVENT used for evaluation without detected set cells; or

2> if any of those non-used frequency triggered while considering detected set cells but did not simultaneously trigger while not considering detected set cells and is not stored either in the variable TRIGGERED_2E_EVENT used for evaluation without detected set cells or in the variable TRIGGERED_2E_EVENT used for evaluation with detected set cells; or

3> store the non-used frequencies that triggered the event and that were not previously stored in the variable TRIGGERED_2E_EVENT corresponding to the virtual active set being evaluated into that variable;

3> send a measurement report with IEs set as below:

4> set in "inter-frequency measurement event results":

5> "inter-frequency event identity" to "2e"; and

5> for each non-used frequency that triggered the event, beginning with the best frequency:

6> "Frequency info" to that non-used frequency; and

6> if the frequency triggered the event due to considering detected set cells:

7> set the IE "Detected Set Trigger".

4> include in the IE "Inter-frequency measured results list" the measured results for each non-used frequency that triggered the event, not taking into account the cell individual offset;

4> set the IE "additional measured results" according to subclause 8.4.2, not taking into account the cell individual offset.

1> if equation 1 below has been fulfilled but the CSG virtual active set is updated for a non-used frequency included for that event:

2> restart evaluation of this event for this frequency.

1> if equation 2 below is fulfilled for a non-used frequency stored in the variable TRIGGERED_2E_EVENT:

2> remove that non-used frequency from the variable TRIGGERED_2E_EVENT corresponding to the virtual active set being evaluated.

Triggering condition:

Equation 1:

The variables in the formula are defined as follows:

Q_{Non used}is the quality estimate of a non-used frequency that becomes worse than an absolute threshold.

T_{Non used 2e} is the absolute threshold that applies for that non-used frequency for that event.

H_2e is the hysteresis parameter for the event 2e.

Leaving triggered state condition:

Equation 2:

The variables in the formula are defined as follows:

Q_{Non used}is the quality estimate of a non-used frequency stored in the variable TRIGGERED_2E_EVENT.

T_{Non used 2e} is the absolute threshold that applies for that non-used frequency for that event.

H_2e is the hysteresis parameter for the event 2e.

14.2.1.6 Event 2 f: The estimated quality of the currently used frequency is above a certain threshold

A UE shall be able to perform this measurement and the corresponding event reporting without requiring compressed mode.

When an inter-frequency measurement configuring event 2f is set up, the UE shall:

1> create a variable TRIGGERED_2F_EVENT related to that measurement, which shall initially be set to FALSE;

1> delete this variable when the measurement is released.

When event 2f is configured in the UE within a measurement, the UE shall:

1> if equation 1 below has been fulfilled for the used frequency during the time "Time to trigger":

2> if the variable TRIGGERED_2F_EVENT is set to FALSE:

3> set the variable TRIGGERED_2F_EVENT to TRUE;

3> send a measurement report with IEs set as below:

4> set in "inter-frequency event results": "inter-frequency event identity" to "2f", and no IE "Inter-frequency cells";

4> include in IE "Inter-frequency measured results list" the measured results for the used frequency, not taking into account the cell individual offset;

4> set the IE "additional measured results" according to subclause 8.4.2, not taking into account the cell individual offset.

1> if the variable TRIGGERED_2F_EVENT is set to TRUE and if equation 2 is fulfilled for the used frequency:

2> set the variable TRIGGERED_2F_EVENT to FALSE.

Triggering condition:

Equation 1:

The variables in the formula are defined as follows:

Q_Usedis the quality estimate of the used frequency.

T_{Used 2f} is the absolute threshold that applies for the used frequency and event 2f.

H_2f is the hysteresis parameter for the event 2f.

Leaving triggered state condition:

Equation 2:

The variables in the formula are defined as follows:

Q_Usedis the quality estimate of the used frequency.

T_{Used 2f} is the absolute threshold that applies for the used frequency and event 2f.

H_2f is the hysteresis parameter for the event 2f.

14.2.1.7 Event 2g: Change of best cell on a configured secondary downlink frequency (FDD only)

In the description below, the "virtual active set" should be understood as the secondary E-DCH active set if the frequency is the downlink frequency associated with the secondary uplink frequency. Otherwise, the "virtual active set" is the virtual active set for cells only in the CELL_INFO_LIST. The way the virtual active set is initiated and updated is described in subclause 14.11.

When an inter-frequency measurement configuring event 2g is set up, the UE shall:

1> create a variable BEST_CELL_2G_EVENT per virtual active set related to that measurement, which shall initially contain the secondary serving HS-DSCH cell on each secondary downlink frequency;

1> delete this variable when the measurement is released.

When event 2g is configured in the UE within a measurement, the UE shall:

1> if IE "useCIO" is present and its value is TRUE, take into account the Cell Individual Offset for evaluation of the Equation 1, otherwise do not take it into account;

1> if Equation 1 below has been fulfilled for a time period indicated by "time to trigger" for a primary CPICH that is not stored in "Best cell" in variable BEST_CELL_2G_EVENT for one or several non-used frequencies:

NOTE: If the equations are simultaneously fulfilled for more than one primary CPICH on one frequency, the UE should report only one event 2g on that frequency, triggered by the best primary CPICH.

2> if all required reporting quantities are available for that cell, and that primary CPICH is part of cells in "Cells for measurement" or in CELL_INFO_LIST if "Cells for measurement" is not present:

3> set the "Frequency" to the frequency that triggered the event and "best cell" to that primary CPICH that triggered the event in the variable BEST_CELL_2G_EVENT;

3> send a measurement report with IEs set as below:

4> set in "inter-frequency measurement event results":

5> "inter-frequency event identity" to "2g"; and

5> for each non-used frequency that triggered the event:

6> "Frequency info" to that frequency; and

6> "Non frequency related measurement event results" to the "Primary CPICH info" of the primary CPICH stored in the BEST_CELL_2G_EVENT variable.

4> include in IE "Inter-frequency measured results list" the measured results for each non-used frequency that triggered the event;

4> set the IE "additional measured results" according to subclause 8.4.2.

This event is only applicable to the CELL_DCH state. Upon transition to CELL_DCH the UE shall:

1> set the "Frequency" to each secondary downlink frequency and "best cell" in the variable BEST_CELL_2G_EVENT to the secondary serving HS-DSCH cell on each secondary downlink frequency.

Equation 1

The variables in the formula are defined as follows:

M_NotBest is the measurement result of a cell not stored in "best cell" in the variable BEST_CELL_2G_EVENT on the related frequency.

CIO_NotBest is the cell individual offset of a cell not stored in "best cell" in the variable BEST_CELL_2G_EVENT on the related frequency.

M_Best is the measurement result of the cell stored in "best cell" in variable BEST_CELL_2G_EVENT on the related frequency.

CIO_Best is the cell individual offset of a cell stored in "best cell" in the variable BEST_CELL_2G_EVENT on the related frequency.

H_2g is the hysteresis parameter for the event 2g.

If the measurement result is CPICH-Ec/No then M_{Not Best} and M_Best are expressed as ratios.

If the measurement result is CPICH-RSCP then M_{Not Best} and M_Best are expressed in mW.

Figure 14.2.1.7-1 [Informative]: A primary CPICH becomes better than the previously best primary CPICH on a configured secondary downlink frequency

In this figure, the parameters hysteresis and time to trigger, as well as the cell individual offsets for all cells are equal to 0.