6 MS Requirements for Synchronization
3GPP45.010GSM/EDGE Radio subsystem synchronizationTS
6.0 General
The MS shall only start to transmit to the BTS if the requirements of subclauses 6.1 to 6.4 are met.
The conditions under which the requirements of subclauses 6.1 to 6.4 must be met shall be 3 dB below the reference sensitivity level or input level for reference performance, whichever applicable, in 3GPP TS 45.005 and 3 dB less carrier to interference ratio than the reference interference ratios or the interference ratios for reference performance, whichever applicable, in 3GPP TS 45.005. For EC-GSM-IoT, the conditions shall be met at the input signal level and at the interference ratios of EC-SCH at reference performance, as defined in 3GPP TS 45.005.
In discontinuous reception (DRX), the MS should meet the requirements of subclauses 6.1 to 6.3 during the times when the receiver is required to be active.
For CTS, the CTS-MS shall fulfil all the requirements of subclauses 6.1 to 6.4, 6.7, 6.8, 6.10 and 6.11 where «BTS» designates the CTS-FP. The CTS-MS shall always use a TA value of zero. The CTS-MS shall only start to transmit to the CTS-FP if the requirements of subclauses 6.1 to 6.4 are met. The conditions under which the requirements of subclauses 6.1 to 6.4 must be met shall be 3 dB below the reference sensitivity level or input level for reference performance, whichever applicable, in 3GPP TS 45.005 and 3 dB less carrier to interference ratio than the reference interference ratios in 3GPP TS 45.005. In discontinuous reception (DRX), the CTS-MS should meet the requirements of subclauses 6.1 to 6.3 during the times when the receiver is required to be active.
6.1 MS carrier frequency
The MS carrier frequency shall be accurate to within 0.1 ppm, or accurate to within 0.1 ppm compared to signals received from the BTS, except for GSM 400 where 0.2 ppm shall apply in both case (these signals will have an apparent frequency error due to BTS frequency error and Doppler shift). In the latter case, the signals from the BTS must be averaged over sufficient time that errors due to noise or interference are allowed for within the above 0.1 ppm and 0.2 ppm figure. The MS shall use the same frequency source for both RF frequency generation and clocking the timebase.
6.2 Internal timebase
The MS shall keep its internal timebase in line with that of signals received from the BTS. If the MS determines that the timing difference exceeds 2 µ seconds, it shall adjust its timebase in steps of ¼ normal symbol period. This adjustment shall be performed at intervals of not less than 1 second and not greater than 2 seconds until the timing difference is less than ½ normal symbol periods.
6.3 Assessment of BTS timing
6.3.1 General
In determining the timing of signals from the BTS, the timings shall be assessed in such a way that the timing assessment error is less than ½ normal symbol periods. The assessment algorithm must be such that the requirements of 6.2 can be met.
6.3.2 MS Assessment of BTS timing for Positioning
A higher level of accuracy of the assessment of the BTS timing by the MS (reported to the SMLC, see 3GPP TS 43.059 [6]) is desired when the following positioning procedures are used:
– Multilateration Timing Advance procedure for assessing the TA in the serving cell and in non-serving cells, and
– Multilateration Observed Time Difference procedure for assessing the TA in the serving cell,The Initial LLC-PDU received from the MS;
During the positioning procedure the minimum requirement on the error assessment of the BTS timing by the MS at and above the reference sensitivity level of the SCH or, in the case of EC operation, at and above the input signal level of the EC-SCH at reference performance, shall be [± ¼] normal symbol period unless the MS Sync Accuracy the MS can realize when performing the positioning procedure in a given cell meets a tighter requirement for the assessment of the BTS timing than the default value (indicated in the MSRAC IE – see 3GPP TS 24.008). In this case the value of the MS Sync Accuracy sent by the MS indicates the tighter requirement. Furthermore, to meet the targeted positioning accuracy for a targeted number of BTSs the SMLC determines a target assessment of BTS timing required of the MS and includes this as the Requested MS Sync Accuracy in the triggering RRLP message when indicating to the MS to use the RLC Data block or Extended Access burst method (see 3GPP TS 43.059 [6] and 3GPP TS 49.031[18]).
The MS shall attempt to achieve the Requested MS Sync Accuracy using a minimum of 2 or a maximum of [10] repeated synchronizations to the same BTS and report the achieved error in the assessment of the sync accuracy (i.e. assessment of BTS timing on the downlink) in the uplink RLC data block or the Extended Access Burst as the MS Sync Accuracy. The error of the sync accuracy corresponds to the variance of the estimated timing of multiple repeated synchronizations according to the equations below where N denotes the number of independent synchronization attempts and ti, i=1…N denotes the estimated timing in synchronization ‘i’.
The variance 
of the estimated timing shall be evaluated using the formula:
s2 is the unbiased sample variance
and 
is the mean of 
, i.e.
Similarly, to support accurate positioning using the Multilateration Observed Time Difference (OTD) procedure, a higher level of accuracy of the assessment of BTS timing is required in order to determine the difference in arrival time between (EC-)SCH synchronization sequences of two base station transmissions which is reported to the network in the RRLP Multilateration OTD Response message. At and above the reference senstivity level of the SCH or, in the case of EC operation, at and above the input signal level of the EC-SCH at reference performance (see 3GPP TS 45.005 [11]), the absolute value of a Multilateration OTD report’s error shall be ≤ ¼ normal symbol period. An MS applying the Multilateration OTD procedure shall report in the OTD Measurement Information IE the achieved assessment error of the BTS timing, according to the formulas above in this clause, as the MS Sync Accuracy for the respective neighbour cell.
6.4 Timing of transmission
The MS shall time its transmissions to the BTS according to signals received from the BTS. The MS transmissions to the BTS, measured at the MS antenna, shall be 468,75‑TA normal symbol periods (i.e. 3 timeslots‑TA) behind the transmissions received from the BTS, where TA is the last timing advance received from the current serving BTS. The tolerance on these timings shall be ± 1 normal symbol period. For CTS, the tolerance on these timings shall be ± ½ normal symbol period.
For an MS that transmits to a BTS in response to a RRLP Multilateration Timing Advance Request or RRLP Multilateration Observed Time Difference message (see 3GPP TS 43.059 [6]) the requirement on tolerance on the timings of its transmissions, when operating at and above the reference sensitivity level of the SCH or, in the case of EC operation, at and above the input signal level of the EC-SCH at reference performance (see 3GPP TS 45.005 [11]), shall be [ ±1/8] normal symbol period or better. In addition, immediately prior to transmitting to a BTS while performing Multilateration Timing Advance procedure using the RLC Data Block method or the Extended Access Burst Method (see 3GPP TS 44.018 [8] and 3GPP TS 43.059 [6]), the MS shall also calculate the offset between the nominal transmission opportunity, as determined in relation to the estimated timing of the BTS, and the selected transmission opportunity, as dictated by the internal timebase. The offset shall be reported as the MS Transmission Offset in the uplink RLC data block or in the Extended Access Burst [6]. If the selected uplink transmission opportunity occurs earlier than the nominal transmission opportunity, the MS transmission Offset shall be reported as a positive value. Similarly, if the selected uplink transmission opportunity occurs later than the nominal transmission opportunity, the MS transmission Offset shall be reported as a negative value. Note that upon receiving an assigned TA value the resulting new transmission opportunity (selected according to the nearest available timebase specific transmission opportunity identified after applying the indicated TA value) needs to be in the same direction as before, i.e., if before receiving an assigned TA value the selected uplink transmission opportunity (selected using the nearest available timebase specific transmission opportunity) occurred earlier than the nominal transmission opportunity then the MS shall establish a new nominal transmission opportunity using the indicated TA value and then select an uplink transmission opportunity (selected using the nearest available timebase specific transmission opportunity) that occurs earlier than the new nominal transmission opportunity (and similarly for the case where the selected uplink transmission opportunity occurred later than the nominal transmission opportunity).
In case of a multislot configuration, the MS shall use a common timebase for transmission of all channels. In this case, if the MS, not in EC operation, does not support transmission of reduced symbol period bursts, it may optionally use a timeslot length of 157 normal symbol periods on timeslots TN = 0 and 4, and 156 normal symbol periods on timeslots with TN = 1, 2, 3, 5, 6 and 7, rather than 156,25 normal symbol periods on all timeslots. An EC-GSM-IoT MS, when in EC operation, shall use the timeslot length with integer symbol periods, see subclause 5.7.2.
If the MS supports reduced symbol period transmissions, it shall use a timeslot length of 187.5 reduced symbol periods or a timeslot of length 156.25 normal symbol periods. When there is a pair of different symbol period bursts on adjacent timeslots, then the guard period between the two bursts shall be 8.5 normal symbol periods which equals 10.2 reduced symbol periods. The active part of a reduced symbol period burst shall start a quarter of a normal symbol period later compared to a normal symbol period burst as shown in Figure 5.7.3.
In case of a circuit switched multislot configuration, the common timebase shall be derived from the main channel and the TA values received on other channels shall be neglected. In case of a packet switched multislot configuration the common timebase shall be derived from all timeslots monitored by the MS. In this case, the MS may assume that the BTS uses a timeslot length of 156,25 normal symbol periods on all timeslots using normal symbol period and a timeslot length of 187,5 reduced symbol periods on all timeslots using reduced symbol period. In the case of a combination of circuit and packet switched channel configuration the MS may derive the common timebase from the circuit switched channel only.
6.5 Application of Timing Advance
6.5.1 For circuit switched channels
When the MS receives a new value of TA from the BTS on the SACCH, it shall implement the new value of TA at the first TDMA frame belonging to the next reporting period (as defined in 3GPP TS 45.008), after the SACCH frame containing the new TA value. On channels used for a voice group call, the TA value sent by the BTS applies only to an MS currently allocated the uplink.
The MS shall signal the used TA to the BTS on the SACCH.
6.5.2 For packet switched channels
The following requirements apply for all MS in packet transfer mode or in broadcast/multicast receive mode:
The MS shall transmit access bursts (AB, see 3GPP TS 45.002) with TA value=0.
Within the packet resource assignments (see 3GPP TS 44.018 and 3GPP TS 44.060) for uplink or downlink messages the MS gets the Timing Advance Index (TAI). If a PTCCH subchannel is assigned to the MS, the MS shall send access bursts on the subchannel defined by the TAI on the PTCCH. These access bursts received on PTCCH are used by the BTS to derive the timing advance.
When the MS receives the updated value of TA from the BTS on the downlink PTCCH, it shall always use the last received TA value for the uplink transmission of normal bursts.
If an MS is allocated different TAI values for simultaneous uplink and downlink packet transfer, the MS may choose to use any one or both PTCCH subchannels. If two subchannels are used, the MS shall always use the received TA value corresponding to the last transmitted PTCCH uplink burst. If the MS has been assigned TAIs for both UL and DL and if either the last UL or the last DL TBF is released, the MS shall use the TAI assigned for the remaining direction of data transfer.
If the MS receives a packet resource assignment or power control/timing advance message (see 3GPP TS 44.018 and 3GPP TS 44.060) without a TAI for the corresponding UL or DL TBFs, the MS shall not use the old assigned TAI for the continuous timing advance procedure for that direction of data transfer. If no more TAIs are valid the MS shall not perform the continuous timing advance procedure at all.
Upon initiation of the continuous timing advance procedure the MS shall disregard the TA values on PTCCH until it has sent its first access burst on PTCCH.
The network may request the MS to send 4 access bursts to calculate a new TA value. For this purpose, the network sets the system information element CONTROL_ACK_TYPE to indicate that the MS is to respond with a PACKET_CONTROL_ACKNOWLEDGEMENT consisting of 4 access bursts (see 3GPP TS 44.060), and sends a PACKET_POLLING_REQUEST to the MS. In this case, the MS shall transmit 4 consecutive access bursts on the assigned resources.
If the MS receives a packet resource assignment or power control/timing advance message (see 3GPP TS 44.018 and 3GPP TS 44.060), the MS shall use the included TA value for normal burst transmissions until it receives a new value on PTCCH. If the message does not contain a TA value, the MS shall not change its TA value.
When entering packet transfer mode or broadcast/multicast receive mode, the MS is not allowed to transmit normal bursts until it has received a valid TA value by any of the methods described above.
An MS in dual transfer mode shall follow the procedures described in subclause 6.5.1. If the CS connection is released and the MS leaves dual transfer mode to enter packet transfer mode, the MS shall follow the procedures described in the present subclause. The MS shall perform the continuous timing advance procedure if a TAI is contained in the packet CS release indication message (see 3GPP TS 44.060). The mobile station shall use the last value of the timing advance received whilst in dual transfer mode until a new value of the timing advance is determined from the continuous timing advance procedure or is received from the network.
6.6 Access to a new BTS
When the MS accesses a new BTS or the serving BTS is changed, or the MS initiates a packet transfer, or the MS performs a multilateration access attempt using the Access burst method or Extended Access Burst method (see 3GPP TS 43.059), the MS shall change the TA as follows:
Random access and Packet random access:
– the MS shall use a TA value of 0 for the Random Access burst (AB), Extended Synchronisation Access Burst (ESAB) and Extended Dual Slot Access Burst (EDAB), see 3GPP TS 45.002. When a TA is received from the BTS that TA shall be used.
– the MS shall use the assigned TA value received within a corresponding Acknowledgement on the (EC‑)AGCH for the Extended Access Burst (Extended AB), see 3GPP TS 45.002.
Synchronized or Pseudo Synchronized circuit-switched handover:
– after the HANDOVER ACCESS bursts which shall be sent with a TA value of 0 the MS shall use a TA calculated as specified in annex A. When a TA is received from the new BTS that TA shall be used. The transmission of the HANDOVER ACCESS bursts is optional if so indicated by the BTS.
Synchronized packet-switched handover:
– after the PS HANDOVER ACCESS bursts which shall be sent with a TA value of 0 the MS shall use a TA calculated as specified in annex A. When a TA is received from the new BTS that TA shall be used. The transmission of the PS HANDOVER ACCESS bursts is optional if so indicated by the BTS.
In those cells that support extended TA values if TA value in new cell is greater than 63 and the HANDOVER COMMAND message indicates that the transmission of four HANDOVER ACCESS messages is optional the MS shall not transmit these four messages.
Non‑synchronized circuit-switched handover:
– the MS shall use a TA value of 0 for the HANDOVER ACCESS bursts sent. When a TA is received in a PHYSICAL INFORMATION message that TA shall be used. Before a TA is received from the new BTS no valid "used TA" shall be signalled to the new BTS.
Non‑synchronized packet-switched handover:
– the MS shall use a TA value of 0 for the PS HANDOVER ACCESS bursts sent. When a TA is received in a PACKET PHYSICAL INFORMATION message that TA shall be used. Before a TA is received from the new BTS no valid "used TA" shall be signalled to the new BTS.
Pre‑synchronized circuit-switched handover:
– after the HANDOVER ACCESS bursts which shall be sent with a TA value of 0 the MS shall use a TA as specified in the HANDOVER COMMAND message by the old BTS, or a default value of 1, if the old BTS did not provide a TA value. The transmission of the HANDOVER ACCESS bursts is optional if so indicated by the BTS.
Pre‑synchronized packet-switched handover:
– after the PS HANDOVER ACCESS bursts which shall be sent with a TA value of 0 the MS shall use a TA as specified in the PS HANDOVER COMMAND message by the old BTS, or a default value of 1, if the old BTS did not provide a TA value. The transmission of the PS HANDOVER ACCESS bursts is optional if so indicated by the BTS.
In those cells that support extended TA values if TA value in new cell is greater than 63 and the HANDOVER COMMAND message (respectively PS HANDOVER COMMAND message) indicates that the transmission of four HANDOVER ACCESS messages (respectively PS HANDOVER ACCESS messages) is optional the MS shall not transmit these four messages.
6.7 Temporary loss of signal
During a temporary total loss of signal, of up to 64 SACCH block periods, the MS shall update its timebase with a clock which is accurate to within 0,2 ppm, or to within 0,2 ppm of the signals previously received from the BTS.
6.8 Timing of channel change
When the MS receives an intracell channel change command or a circuit-switched handover command (see 3GPP TS 44.018) or a packet-switched handover command (see 3GPP TS 44.060), it shall be ready to transmit on the new channel within T_GSM_Delay of the last timeslot of the message block containing the command, unless the access is delayed to an indicated starting time, in which case it shall be ready to transmit on the new channel at the designated starting time, or within T_GSM_Delay, whichever is the later. The time between the end of the last complete speech or data frame or message block sent on the old channel and the time the MS is ready to transmit on the new channel shall be less than T_GSM_Interrupt.
T_GSM_Delay and T_GSM_Interrupt are defined in table 6.8.1.
Table 6.8.1: Channel change delay and interruption times.
|
Target cell |
T_GSM_Delay (ms) (Note 1) |
T_GSM_Interrupt (ms) |
|
Synchronized GSM cell |
120 ms |
20 ms |
|
Not Synchronized GSM cell Under good radio conditions |
220 ms |
120 ms |
|
NOTE 1: In case of packet-switched handover, if the MS is required to transmit a PACKET CONTROL ACKNOWLEDGMENT message (see 3GPP TS 44.060), T_GSM_delay is increased by 40 ms. |
||
6.9 Application of new Timing Advance value
When the MS receives a new TA value in response to a handover access burst, the MS shall be ready to transmit using the new TA value within 40 ms of the end of the last timeslot of the message block containing the new TA value.
When the MS receives a new or updated TA value on the downlink PTCCH or downlink PACCH, the MS shall be ready to transmit using the new TA value within 40 ms of the end of the last timeslot of the message block containing the new TA value.
6.10 Definition of "ready to transmit within x ms"
The phrase "ready to transmit within x ms" means that the MS shall transmit no later than the first allowed transmission opportunity that occurs after the x ms, e.g. :
– the first burst of the first TCH or control channel block that occurs after the x ms, in case of an intracell channel change;
– the first burst of the TCH or control channel that occurs after the x ms, in case of a handover;
– the first burst of the PDTCH, EC-PDTCH or control channel that occurs after the x ms;
– the first allowed uplink frame (see 3GPP TS 25.212 and 3GPP TS 25.214 for FDD and 3GPP TS 25.222 for TDD), that occurs after the x ms, in case of an inter-RAT handover to a UTRAN cell.
– the first uplink PRACH frame or (for TDD only) UpPTS field (see 3GPP TS 36.211) that occurs after the x ms, in case of an inter-RAT handover to a E-UTRAN cell.
NOTE: The MS shall keep the timings of the neighbour GSM cells that it is monitoring (according to 3GPP TS 45.008) to an accuracy of ± 1 normal symbol periods.
6.11 Definition of additional reaction times for GPRS mobile stations
6.11.1 Uplink and downlink assignment reaction times
An MS shall be ready to transmit and receive using a new assignment 9 frame periods after the last radio block containing the assignment message. A mobile station that receives an assignment message for a new or ongoing TBF with FANR activated (see 3GPP TS 44.060) shall be ready to transmit and receive using the new assignment in the TDMA frame indicated in Table 6.11.1.1 where N = the last TDMA frame of the downlink block containing the assignment message.
Table 6.11.1.1: Assignment Reaction Time for a TBF with FANR activated
|
Assignment message block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+5 or N+6) mod 2715648 |
|
RTTI |
(N+5 or N+6) mod 2715648 |
If the MS is required to transmit a PACKET CONTROL ACKNOWLEDGEMENT, or, in case of EC operation, the MS is required to transmit an EC PACKET CONTROL ACKNOWLEDGEMENT, subsequent to an assignment message (see 3GPP TS 44.060), the MS shall be ready to transmit and receive, or in case of EC operation transmit or receive, on the new assignment (i.e. after transmitting the PACKET CONTROL ACKNOWLEDGMENT, or, in case of EC operation, the EC PACKET CONTROL ACKNOWLEDGEMENT, using the old assignment) as follows:
– For a TBF operating in BTTI configuration or an EC TBF not using blind physical layer transmissions (CC1), no later than the next occurrence of block B((x+2) mod 12) where block B(x) is the radio block containing the PACKET CONTROL ACKNOWLEDGEMENT or EC PACKET CONTROL ACKNOWLEDGEMENT, respectively.
– For an EC TBF using blind physical layer transmissions the same reaction times as for BTTI configuration apply, where B(x) refers to the last BTTI period used by the blind physical layer transmissions of the EC PACKET CONTROL ACKNOWLEDGEMENT. For example, if the blind physical layer transmissions occur during two BTTI periods, the reaction time is measured from the last BTTI period used by the blind physical layer transmissions.
– For a TBF operating in RTTI configuration, no later than the next occurrence of block B((x+1) mod 12)b where block Bxa is the radio block containing the PACKET CONTROL ACKNOWLEDGEMENT or no later than the next occurrence of block B((x+2) mod 12)a where block Bxb is the radio block containing the PACKET CONTROL ACKNOWLEDGEMENT (see 3GPP TS 45.002 [10] for an explanation of RTTI radio block indexing applicable to the RTTI configuration).
– If the assignment message changes the TBF from BTTI to RTTI configuration, no later than the next occurrence of block B((x+2) mod 12)a, where block Bx is the radio block containing the PACKET CONTROL ACKNOWLEDGEMENT.
– If the assignment message changes the TBF from RTTI to BTTI configuration, no later than the next occurrence of block B((x+2) mod 12), where block Bxa or Bxb is the radio block containing the PACKET CONTROL ACKNOWLEDGEMENT (see NOTE).
NOTE: This is to ensure the reaction time falls on a BTTI radio block boundary.
The reaction time applies also for the reception of the first USF for dynamic uplink assignment and extended dynamic uplink assignment, including when Shifted USF operation is used.
6.11.2 Change in channel coding scheme commanded by network
Upon receipt of a command from the network to change the channel coding scheme, the MS shall begin to transmit blocks using the new channel coding scheme as follows:
– For a TBF operating in BTTI configuration, or an EC TBF not using blind physical layer transmissions (CC1), no later than the next occurrence of block B((x+3) mod 12) where block B(x) is the radio block containing the command. For an EC TBF using blind physical layer transmissions, B(x) refers to the last BTTI period used by the blind physical layer transmissions of the block containing the command to change the channel coding scheme. For example, if the blind physical layer transmissions occur during two BTTI periods, the reaction time is measured from the last BTTI period used by the blind physical layer transmissions.
– For a TBF operating in RTTI configuration, no later than the next occurrence of block B((x+2) mod 12)b where block Bxa is the radio block containing the command or no later than the next occurrence of block B((x+3) mod 12)a where block Bxb is the radio block containing the command (see 3GPP TS 45.002 [10] for an explanation of RTTI radio block indexing applicable to the RTTI configuration).
6.11.3 Contention resolution reaction time
Upon contention resolution during one phase access, the mobile station shall start transmitting RLC data blocks without the TLLI field as follows:
– For a TBF operating in BTTI configuration, or an EC TBF not using blind physical layer transmissions (CC1), no later than the next occurrence of block B((x+3) mod 12) where block B(x) is the radio block containing the contention resolution message (see 3GPP TS 44.060). For an EC TBF using blind physical layer transmissions, B(x) refers to the last BTTI period used by the blind physical layer transmissions of the contention resolution message. For example, if the blind physical layer transmissions occur during two BTTI periods, the reaction time is measured from the last BTTI period used by the blind physical layer transmissions.
– For a TBF operating in RTTI configuration, no later than the next occurrence of block B((x+2) mod 12)b where block Bxa is the radio block containing the contention resolution message or no later than the next occurrence of block B((x+3) mod 12)a where block Bxb is the radio block containing the contention resolution message (see 3GPP TS 45.002 [10] for an explanation of RTTI radio block indexing applicable to the RTTI configuration).
6.11.4 Reaction time in response to other commanding messages
Upon a receipt of a commanding message or indication from the network requiring an action by the mobile station, if the reaction time for such action is not specified elsewhere, the mobile station shall begin to perform the required action as follows:
– For a TBF operating in BTTI configuration, or an EC TBF not using blind physical layer transmissions (CC1), no later than the next occurrence of block B((x+6) mod 12), where block B(x) is the radio block containing the commanding message or indication from the network. For an EC TBF using blind physical layer transmissions, B(x) refers to the last BTTI period used by the blind physical layer transmissions of the commanding message. For example, if the blind physical layer transmissions occur during two BTTI periods, the reaction time is measured from the last BTTI period used by the blind physical layer transmissions.
– For a TBF operating in RTTI configuration, no later than the next occurrence of block B((x+5) mod 12)b where block Bxa is the radio block containing the commanding message/indication from the network or no later than the next occurrence of block B((x+6) mod 12)a where block Bxb is the radio block containing the commanding message/indication from the network (see 3GPP TS 45.002 [10] for an explanation of RTTI radio block indexing applicable to the RTTI configuration).
6.11.5 PAN related reaction times
A mobile station that receives a PAN corresponding to an uplink TBF with FANR activated (see 3GPP TS 44.060) shall be ready to re-send the first missing uplink RLC data block in the TDMA frame indicated in Table 6.11.5.1 where N = the last TDMA frame of the downlink block containing the PAN.
Table 6.11.5.1: Reaction Time for receiving a downlink PAN
|
PAN block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+5 or N+6) mod 2715648 |
|
RTTI |
(N+5 or N+6) mod 2715648 |
A mobile station that detects a missing/erroneous RLC data block for a downlink TBF with FANR activated (see 3GPP TS 44.060) shall be ready to send an uplink RLC/MAC block for data transfer with a PAN or an EGPRS PACKET DOWNLINK ACK/NACK or EGPRS PACKET DOWNLINK ACK/NACK TYPE 2 message (in the case that there is no uplink RLC data ready for transmission) reflecting the missing/erroneous block in the TDMA frame indicated in Table 6.11.5.2 where N = the last TDMA frame of the downlink block in which the MS detected the problem.
Table 6.11.5.2: Reaction Time for detecting a downlink problem
|
Downlink TBF block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+5 or N+6) mod 2715648 |
|
RTTI |
(N+3 or N+4) mod 2715648 |
6.11.6 DTR related reaction times
A mobile station which is in DTR mode (see 3GPP TS 44.060) and receives a radio block which causes the MS to leave DTR mode shall be ready to receive data on all timeslots, in accordance with its uplink and/or downlink TBF assignment(s) in the TDMA frame indicated in Table 6.11.6.1 or Table 6.11.6.2 where N = the last TDMA frame of the downlink block triggering the leaving of DTR mode.
Table 6.11.6.1: Assignment Reaction Time for leaving DTR – MS supports FANR
|
Radio block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+5 or N+6) mod 2715648 |
|
RTTI |
(N+5 or N+6) mod 2715648 |
Table 6.11.6.2: Assignment Reaction Time for leaving DTR – MS does not support FANR
|
Radio block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+9) mod 2715648 |
A mobile station shall enter DTR mode within the reaction time as specificied in Table 6.11.6.3 or Table 6.11.6.4 where N = the last TDMA frame of the radio block period in which all conditions for entering DTR were met.
Table 6.11.6.3: Assignment Reaction Time for entering DTR – MS supports FANR
|
Radio block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+5 or N+6) mod 2715648 |
|
RTTI |
(N+5 or N+6) mod 2715648 |
Table 6.11.6.4: Assignment Reaction Time for entering DTR – MS does not support FANR
|
Radio block format |
Full-rate PDCH uplink block with TDMA frame number |
|
BTTI |
(N+9) mod 2715648 |
6.12 Observed Frequency Offset (OFO) reported by the CTS-MS
When required the CTS-MS shall compute the Observed Frequency Offset between the CTS-FP and a specified BTS (see 3GPP TS 45.008). The CTS-FP and BTS received signals frequencies shall be estimated with an accuracy of 0,1 ppm, averaging the signals over sufficient time. The conditions under which this requirements must be met shall be 3 dB below the reference sensitivity level or input level for reference performance, whichever applicable, in 3GPP TS 45.005 and 3 dB less carrier to interference ratio than the reference interference ratios in 3GPP TS 45.005.
6.13 Timing of inter-RAT channel change from GSM to UTRAN
When the MS receives a PS HANDOVER COMMAND for packet-switched handover to UTRAN (see 3GPP TS 44.060) or an INTER SYSTEM TO UTRAN HANDOVER COMMAND (see 3GPP TS 44.018), it shall be ready to transmit on the new channel within Tdelay of the last timeslot of the message block containing the command, unless the access is delayed to an indicated starting time, in which case it shall be ready to transmit on the new channel at the designated starting time, or within Tdelay, whichever is the later. The time between the end of the last complete speech or data frame or message block sent on the old channel and the time the MS is ready to transmit on the new cell shall not exceed Tinterrupt. Tdelay and Tinterrupt are defined in table 6.13.1 for the case of inter-RAT handover to a single UTRAN cell assuming good radio conditions.
Table 6.13.1: Inter-RAT handover delay and interruption times.
|
Target cell |
Tdelay (ms) (Note 1) |
Tinterrupt (ms) |
|
Known FDD cell |
220 |
120 |
|
Not known FDD cell |
320 |
220 |
|
Known TDD cell |
190 |
90 |
|
Not known TDD cell |
350 |
250 |
|
NOTE 1: In case of packet-switched handover, if the MS is required to transmit a PACKET CONTROL ACKNOWLEDGMENT message (see 3GPP TS 44.060), Tdelay is increased by 40 ms. |
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6.13a Timing of inter-RAT channel change from GSM to E-UTRAN
When the MS receives a PS HANDOVER COMMAND for packet-switched handover to E-UTRAN (see 3GPP TS 44.060) or an INTER SYSTEM TO E-UTRAN HANDOVER COMMAND (see 3GPP TS 44.018), it shall be ready to transmit on the new channel within Tdelay of the last timeslot of the message block containing the command, unless the access is delayed to an indicated starting time, in which case it shall be ready to transmit on the new channel at the designated starting time, or within Tdelay, whichever is the later. The time between the end of the last complete data frame or message block sent on the old channel and the time the MS is ready to transmit on the new cell shall not exceed Tinterrupt. Tdelay and Tinterrupt are defined in Table 6.13a.1 for the case of inter-RAT handover to a single E-UTRAN cell assuming good radio conditions.
Table 6.13a.1: Inter-RAT handover delay and interruption times.
|
Target cell |
Tdelay (ms) (Note 1) |
Tinterrupt (ms) |
|
Known FDD cell |
150 |
50 |
|
Not known FDD cell |
250 |
150 |
|
Known TDD cell |
150 |
50 |
|
Not known TDD cell |
250 |
150 |
|
NOTE 1: If the MS is required to transmit a PACKET CONTROL ACKNOWLEDGMENT message (see 3GPP TS 44.060), Tdelay is increased by 40 ms. |
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6.14 Timing of combined intracell channel change and packet assignment
When the MS receives a combined intracell channel change command and packet assignment in either dedicated mode or dual transfer mode (see 3GPP TS 44.018), the requirements specified in sub-clause 6.8 shall apply to the new dedicated channel.
In addition, the MS shall be ready to transmit and receive using the packet assignment within T_GSM_delay of the last timeslot of the message block containing the command, unless the access is delayed to an indicated starting time, in which case it shall be ready to transmit on the new channel at the designated starting time, or within T_GSM_Delay, whichever is the later. This applies also for the reception of the first USF for dynamic uplink assignment.
The requirements for using the packet assignment apply also when the MS receives a stand-alone packet assignment (on the main DCCH), causing the transition from dedicated mode into dual transfer mode (see 3GPP TS 44.018).
T_GSM_delay is defined in sub-clause 6.8, table 6.8.1.