7.6.2G Out-of-band blocking for V2X Communication
36.521-13GPPEvolved Universal Terrestrial Radio Access (E-UTRA)Part 1: Conformance testingRadio transmission and receptionRelease 17TSUser Equipment (UE) conformance specification
7.6.2G.1 Out-of-band blocking for V2X Communication/ Non-concurrent with E-UTRA uplink transmissions
7.6.2G.1.1 Test Purpose
Out-of-band blocking for V2X is defined for an unwanted CW interfering signal falling more than 15 MHz below or above the V2X band, at which a given average throughput shall meet or exceed the requirement for the specified measurement channels in aggregated signals.
For the first 15 MHz below or above the V2X band the appropriate in-band blocking or adjacent channel selectivity in sub-clause 7.5G and sub-clause 7.6.1G shall be applied.
The lack of out-of-band blocking ability will decrease the coverage area when other e-NodeB transmitters exist (except in the adjacent channels and spurious response).
7.6.2G.1.2 Test Applicability
This test applies to all types of UE that support V2X Sidelink Communication and Band 47.
7.6.2G.1.3 Minimum Conformance Requirements
The throughput shall be ≥ 95% of the maximum throughput of the reference measurement channels as specified in Annex A.8.2 with parameters specified in Tables 7.6.2G.3-1, 7.6.2G.3-2.
For Table 7.6.2G.3-2 in frequency range 1, 2 and 3, up to 
exceptions are allowed for spurious response frequencies in each assigned frequency channel when measured using a 1MHz step size, where 
is the number of resource blocks in the downlink transmission bandwidth configuration (see Figure 5.4.2-1). For these exceptions the requirements of subclause 7.7G Spurious response are applicable.
Table 7.6.2G.1.3-1: Out-of-band blocking parameters
|
Rx Parameter |
Units |
Channel bandwidth |
|||||
|
1.4 MHz |
3 MHz |
5 MHz |
10 MHz |
15 MHz |
20 MHz |
||
|
Power in Transmission Bandwidth Configuration |
dBm |
PREFSENS_V2X + channel bandwidth specific value below |
|||||
|
6 |
9 |
||||||
|
NOTE 1: Reference measurement channel is specified in TS 36.101 [2] Annex A.8.2. |
|||||||
Table 7.6.2G.1.3-2: Out of band blocking
|
E-UTRA V2X band |
Parameter |
Units |
Frequency |
||
|
Range 1 |
Range 2 |
Range 3 |
|||
|
PInterferer |
dBm |
-44 |
-30 |
-15 |
|
|
47 |
FInterferer (CW) |
MHz |
FDL_low -30 to FDL_low -60 |
FDL_low -60 to FDL_low -85 |
FDL_low -85 to 1 MHz |
|
FDL_high +30 to FDL_high + 60 |
FDL_high +60 to FDL_high +85 |
FDL_high +85 to +12750 MHz |
|||
|
NOTE: The power level of the interferer (PInterferer) for Range 3 shall be modified to -20 dBm for FInterferer > 4400 MHz. |
|||||
NOTE: it is FFS how to accommodate the blocking level of -30dBm in Region 1.
The normative reference for this requirement is TS 36.101 [2] clause 7.6.2.1G.
7.6.2G.1.4 Test Description
7.6.2G.1.4.1 Initial conditions
Initial conditions are a set of test configurations the UE needs to be tested in and the steps for the SS to take with the UE to reach the correct measurement state.
The initial test configurations consist of environmental conditions, test frequencies, and channel bandwidths based on E-UTRA operating bands specified in table 5.4.2G.1-1. All of these configurations shall be tested with applicable test parameters for each channel bandwidth, and are shown in table 7.6.2G.1.4.1-1. The details of the V2X reference measurement channels (RMCs) are specified in Annex A.8.3 and the GNSS configuration in TS 36.508 [7] subclause 4.11.
Table 7.6.2G.1.4.1-1: Test Configuration Table
|
Initial Conditions |
|||
|
Test Environment as specified in TS 36.508[7] subclause 4.1 |
Normal |
||
|
Test Frequencies as specified in TS 36.508 [7] subclause 4.3.1 |
Mid range |
||
|
Test Channel Bandwidths as specified in TS 36.508 [7] subclause 4.3.1 |
Lowest, Highest |
||
|
Test Parameters for Channel Bandwidths |
|||
|
V2X Configuration to Receive |
|||
|
Ch BW |
Modulation |
PSSCH RB allocation |
|
|
10MHz |
QPSK |
48@2 |
|
|
20MHz |
QPSK |
96@2 |
|
1. Connect the SS to the UE antenna connectors and connect the GNSS simulator to the UE GNSS RX antenna connector as shown in TS 36.508 [7] Annex A, Figure A. 92b.
2. The parameter settings for the V2X sidelink transmission over PC5 are pre-configured according to TS 36.508 [7] subclause 6.8.2. Message content exceptions are defined in clause 7.6.2G.1.4.3.
3. The V2X reference measurement channel is set according to Table 7.6.2G.1.4.1-1.
3a. The GNSS simulator is configured for Scenario #1: static in Geographical area #1, as defined in TS36.508 [7] Table 4.11.2-2. Geographical area #1 is also pre-configured in the UE.
4. Propagation conditions are set according to Annex B.0.
5. UE test mode – State 5A-V2X according to TS 36.508 [7] clause 5.2A.2C.
6. Trigger the UE to reset UTC time. (NOTE: The UTC time reset may be performed by MMI or AT command (+CUTCR).
7. The GNSS simulator is triggered to start step 1 of Scenario #1 to simulate a location in the centre of Geographical area #1. Wait for the UE to acquire the GNSS signal and start to transmit.
7.6.2G.1.4.2 Test procedure
1. The UE starts to perform the V2X sidelink communication according to SL-V2X-Preconfiguration. Since the UE has no payload and no loopback data to send the UE sends uplink MAC padding bits on the V2X RMC.
2. Set the downlink signal level according to the table 7.6.2G.1.5-1.
3. Set the parameters of the CW signal generator for an interfering signal below the wanted signal according to Table 7.6.2G.1.5-2. The frequency step size is 1MHz.
4. Measure the average throughput for a duration sufficient to achieve statistical significance according to Annex G.2.
5. Record the frequencies for which the throughput doesn’t meet the requirements.
6. Repeat steps from 3 to 5, using an interfering signal above the wanted signal at step 3.
7.6.2G.1.4.3 Message contents
Message contents are according to TS 36.508 [7] subclause 4.6, 4.7.I and 4.10.
7.6.2G.1.5 Test Requirement
Except for the spurious response frequencies recorded at the final step of test procedure, the throughput measurement derived in test procedure shall be ≥ 95% of the maximum throughput of the reference measurement channels as specified in clause A.3.2 with parameters specified in Tables 7.6.2G.1.5-1 and 7.6.2G.1.5-2
For Table 7.6.2G.1.5-2 in frequency range 1, 2 and 3, the number of spurious response frequencies recorded in the final step of test procedure shall not exceed 
in each assigned frequency channel when measured using a 1MHz step size. For these exceptions the requirements of subclause 7.7G spurious response are applicable.
Table 7.6.2G.1.5-1: Out-of-band blocking parameters
|
Rx Parameter |
Units |
Channel bandwidth |
|||||
|
1.4 MHz |
3 MHz |
5 MHz |
10 MHz |
15 MHz |
20 MHz |
||
|
Power in Transmission Bandwidth Configuration |
dBm |
PREFSENS_V2X + channel bandwidth specific value below |
|||||
|
6 |
9 |
||||||
|
NOTE 1: Reference measurement channel is specified in TS 36.101 [2] Annex A.8.2. |
|||||||
Table 7.6.2G.1.5-2: Out of band blocking
|
E-UTRA V2X band |
Parameter |
Units |
Frequency |
||
|
Range 1 |
Range 2 |
Range 3 |
|||
|
PInterferer |
dBm |
-44 |
-30 |
-15 |
|
|
47 |
FInterferer (CW) |
MHz |
FDL_low -30 to FDL_low -60 |
FDL_low -60 to FDL_low -85 |
FDL_low -85 to 1 MHz |
|
FDL_high +30 to FDL_high + 60 |
FDL_high +60 to FDL_high +85 |
FDL_high +85 to +12750 MHz |
|||
|
NOTE: The power level of the interferer (PInterferer) for Range 3 shall be modified to -20 dBm for FInterferer > 4400 MHz. |
|||||
7.6.2G.2 Out-of-band blocking for V2X Communication / Simultaneous E-UTRA V2X sidelink and E-UTRA uplink transmissions
7.6.2G.2.1 Test Purpose
Same as in clause 7.6.2G.1.1.
7.6.2G.2.2 Test Applicability
This test applies to all types of E-UTRA UE release 14 and forward that support V2X Communication.
7.6.2G.2.3 Minimum Conformance Requirements
The throughput shall be ≥ 95% of the maximum throughput of the reference measurement channels as specified in Annex A.8.2 with parameters specified in Tables 7.6.2G.2.3-1, 7.6.2G.2.3-2.
For Table 7.6.2G.2.3-2 in frequency range 1, 2 and 3, up to 
exceptions are allowed for spurious response frequencies in each assigned frequency channel when measured using a 1MHz step size, where 
is the number of resource blocks in the downlink transmission bandwidth configuration (see Figure 5.4.2-1). For these exceptions the requirements of subclause 7.7G Spurious response are applicable.
Table 7.6.2G.2.3-1: Out-of-band blocking parameters
|
Rx Parameter |
Units |
Channel bandwidth |
|||||
|
1.4 MHz |
3 MHz |
5 MHz |
10 MHz |
15 MHz |
20 MHz |
||
|
Power in Transmission Bandwidth Configuration |
dBm |
PREFSENS_V2X + channel bandwidth specific value below |
|||||
|
6 |
9 |
||||||
|
NOTE 1: Reference measurement channel is specified in TS 36.101 [2] Annex A.8.2. |
|||||||
Table 7.6.2G.2.3-2: Out of band blocking
|
E-UTRA V2X band |
Parameter |
Units |
Frequency |
||
|
Range 1 |
Range 2 |
Range 3 |
|||
|
PInterferer |
dBm |
-44 |
-30 |
-15 |
|
|
47 |
FInterferer (CW) |
MHz |
FDL_low -30 to FDL_low -60 |
FDL_low -60 to FDL_low -85 |
FDL_low -85 to 1 MHz |
|
FDL_high +30 to FDL_high + 60 |
FDL_high +60 to FDL_high +85 |
FDL_high +85 to +12750 MHz |
|||
|
NOTE: The power level of the interferer (PInterferer) for Range 3 shall be modified to -20 dBm for FInterferer > 4400 MHz. |
|||||
When UE is configured for simultaneous E-UTRA V2X sidelink and E-UTRA downlink reception for inter-band E-UTRA V2X / E-UTRA bands specified in Table 5.2G-2, the requirements in subclause 7.6.2G.2.3 apply for the E-UTRA V2X sidelink reception and the requirements in subclause 7.6.2.3 apply for the E-UTRA downlink reception while all downlink carriers are active.
The normative reference for this requirement is TS 36.101 [2] clause 7.6.2.1G.
7.6.2G.2.4 Test Description
7.6.2G.2.4.1 Initial conditions
Initial conditions are a set of test configurations the UE needs to be tested in and the steps for the SS to take with the UE to reach the correct measurement state.
The initial test configurations consist of environmental conditions, test frequencies, and channel bandwidths based on E-UTRA operating bands specified in table 5.4.2G.1-2. All of these configurations shall be tested with applicable test parameters for each channel bandwidth, and are shown in table 7.6.2G.2.4.1-1. The details of the uplink, downlink and V2X reference measurement channels (RMCs) are specified in Annexes A.2, A.3 and A.8.3 respectively.
Table 7.6.2G.2.4.1-1: Test Configuration Table
|
Initial Conditions |
|||||||
|
Test Environment as specified in TS 36.508[7] subclause 4.1 |
Normal |
||||||
|
Test Frequencies as specified in TS 36.508 [7] subclause 4.3.1 |
Mid range |
||||||
|
Test Channel Bandwidths as specified in TS 36.508 [7] subclause 4.3.1 |
Lowest, 5MHz, Highest for uplink Lowest, Highest for V2X |
||||||
|
Test Parameters for Channel Bandwidths |
|||||||
|
Downlink |
Uplink Configuration |
V2X Configuration |
|||||
|
Ch BW |
Mod’n |
RB allocation |
Mod’n |
RB allocation |
Ch BW |
Mod’n |
PSSCH RB allocation |
|
1.4 MHz |
QPSK |
1 |
QPSK |
1 |
10 MHz |
QPSK |
48@2 |
|
1.4 MHz |
QPSK |
5 |
QPSK |
5 |
20 MHz |
QPSK |
96@2 |
|
3 MHz |
QPSK |
1 |
QPSK |
1 |
|||
|
3 MHz |
QPSK |
4 |
QPSK |
4 |
|||
|
5 MHz |
QPSK |
1 |
QPSK |
1 |
|||
|
5 MHz |
QPSK |
8 |
QPSK |
8 |
|||
|
10 MHz |
QPSK |
1 |
QPSK |
1 |
|||
|
10 MHz |
QPSK |
12 |
QPSK |
12 |
|||
|
15 MHz |
QPSK |
1 |
QPSK |
1 |
|||
|
15 MHz |
QPSK |
16 |
QPSK |
16 |
|||
|
20 MHz |
QPSK |
1 |
QPSK |
1 |
|||
|
20 MHz |
QPSK |
18 |
QPSK |
18 |
|||
|
Note 1: Test Channel Bandwidths are checked separately for each E-UTRA band, the applicable channel bandwidths are specified in Table 5.4.2.1-1. Note 2: Depending on E-UTRA band, only the appropriate Uplink RB allocation value according to table 7.3G.0-4 is tested per Test Channel Bandwidth. The allocation shall be located as close as possible to the downlink operating band but confined within the transmission bandwidth configuration for the channel bandwidth (Table 5.4.2G.1-2). |
|||||||
1. Connect the SS to the UE antenna connectors as shown in TS 36.508 [7] Annex A, Figure 93c.
2. The parameter settings for the cell are set up according to TS 36.508 [7] subclause 4.4.3. Message content exceptions are defined in clause 7.6.2G.2.4.3.
3. Downlink signals are initially set up according to Annex C.0, C.1, and C.3.0, and uplink signals according to Annex H.1 and H.3.0.
4. The UL and V2X Reference Measurement Channels are set according to Table 7.6.2G.2.4.1-1.
5. Propagation conditions are set according to Annex B.0.
6. Ensure the UE is in State 3A-RF-V2X according to TS 36.508 [7] clause 5.2A.2C. Message content exceptions are defined in clause 7.6.2G.2.4.3.
7.6.2G.2.4.2 Test procedure
1. The SS transmits PDSCH via PDCCH DCI format 1A for C_RNTI to transmit the DL RMC according to Tables 7.6.2G.2.4.1-1 on E-UTRA Band. The SS sends downlink MAC padding bits on the DL RMC.
2. SS simultaneously sends uplink scheduling information for each UL HARQ process via PDCCH DCI format 0 for C_RNTI to schedule the UL RMC and V2X scheduling information via PDCCH DCI format 5A for SL_V_RNTI to schedule the V2X RMC according to Table 7.6.2G.2.4.1-1. Since the UE has no payload and no loopback data to send the UE sends uplink MAC padding bits on the UL and V2X RMCs.
3. Set the downlink signal level according to the table 7.6.2G.2.5-1.
4. Set the parameters of the CW signal generator for an interfering signal below the wanted signal according to Table 7.6.2G.2.5-2. The frequency step size is 1MHz.
5. Measure the average throughput for a duration sufficient to achieve statistical significance according to Annex G.2.
6. Record the frequencies for which the throughput doesn’t meet the requirements.
7. Repeat steps from 4 to 6, using an interfering signal above the wanted signal at step 4.
7.6.2G.2.4.3 Message contents
Message contents are according to TS 36.508 [7] subclause 4.6.
7.6.2G.2.5 Test Requirement
Except for the spurious response frequencies recorded at the final step of test procedure, the throughput measurement derived in test procedure shall be ≥ 95% of the maximum throughput of the reference measurement channels as specified in clause A.3.2 with parameters specified in Tables 7.6.2G.2.5-1 and 7.6.2G.2.5-2
For Table 7.6.2G.2.5-2 in frequency range 1, 2 and 3, the number of spurious response frequencies recorded in the final step of test procedure shall not exceed 
in each assigned frequency channel when measured using a 1MHz step size. For these exceptions the requirements of subclause 7.7G spurious response are applicable.
Table 7.6.2G.2.5-1: Out-of-band blocking parameters
|
Rx Parameter |
Units |
Channel bandwidth |
|||||
|
1.4 MHz |
3 MHz |
5 MHz |
10 MHz |
15 MHz |
20 MHz |
||
|
Power in Transmission Bandwidth Configuration |
dBm |
PREFSENS_V2X + channel bandwidth specific value below |
|||||
|
6 |
9 |
||||||
|
NOTE 1: Reference measurement channel is specified in TS 36.101 [2] Annex A.8.2. |
|||||||
Table 7.6.2G.2.5-2: Out of band blocking
|
E-UTRA V2X band |
Parameter |
Units |
Frequency |
||
|
Range 1 |
Range 2 |
Range 3 |
|||
|
PInterferer |
dBm |
-44 |
-30 |
-15 |
|
|
47 |
FInterferer (CW) |
MHz |
FDL_low -30 to FDL_low -60 |
FDL_low -60 to FDL_low -85 |
FDL_low -85 to 1 MHz |
|
FDL_high +30 to FDL_high + 60 |
FDL_high +60 to FDL_high +85 |
FDL_high +85 to +12750 MHz |
|||
|
NOTE: The power level of the interferer (PInterferer) for Range 3 shall be modified to -20 dBm for FInterferer > 4400 MHz. |
|||||
7.6.2G.3 Out-of-band blocking for V2X Communication / Intra-band contiguous multi-carrier operation
7.6.2G.3.1 Test Purpose
Same as in clause 7.6.2G.1.1.
7.6.2G.3.2 Test Applicability
This test applies to all types of UE that support Intra-band contiguous multi-carrier operation V2X Sidelink Communication and Band 47.
7.6.2G.3.3 Minimum Conformance Requirements
For intra-band contiguous multi-carrier operation, the V2X UE throughput shall be ≥ 95% of the maximum throughput of the reference measurement channels as specified in Annex A.8.2 with parameters specified in Tables 7.6.2G.3.3-1 and 7.6.2G.3.3-2.
For Table 7.6.2G.3.3-2 in frequency range 1, 2 and 3, up to 
exceptions are allowed for spurious response frequencies in each assigned frequency channel when measured using a 1MHz step size. For these exceptions the requirements of subclause 7.7 spurious response are applicable.
Table 7.6.2G.3.3-1: Out-of-band blocking parameters for intra-band contiguous multi-carrier for V2X UE
|
Rx Parameter |
Units |
V2X Bandwidth Class |
||||
|
B |
C |
D |
E |
F |
||
|
Pw in Transmission Bandwidth Configuration, per CC |
dBm |
REFSENS + V2X Bandwidth Class specific value below |
||||
|
9 |
||||||
Table 7.6.2G.3.3-2: Out of band blocking for intra-band contiguous multi-carrier for V2X UE
|
V2X multi-carrier configuration |
Parameter |
Units |
Frequency |
||
|
Range 1 |
Range 2 |
Range 3 |
|||
|
PInterferer |
dBm |
-44 |
-30 |
-15 |
|
|
V2X_47B |
FInterferer (CW) |
MHz |
FDL_low -30 to FDL_low -60 |
FDL_low -60 to FDL_low -85 |
FDL_low -85 to 1 MHz |
|
FDL_high +30 to FDL_high + 60 |
FDL_high +60 to FDL_high +85 |
FDL_high +85 to +12750 MHz |
|||
|
NOTE 1: The power level of the interferer (PInterferer) for Range 3 shall be modified to -20 dBm for FInterferer > 4400 MHz. NOTE 2: The requirement is applied for 2 carrier intra-concurrent receptions when 2 carrier transmission are activated at the same time |
|||||
The normative reference for this requirement is TS 36.101 [2] clause 7.6.2.1G.
7.6.2G.3.4 Test Description
7.6.2G.3.4.1 Initial conditions
Same initial conditions as in clause 7.6.2G.1.4.1 with the following exceptions- Instead of Table 7.6.2G.1.4.1-1 🡪 use Table 7.6.2G.3.4.1-1.
The details of the GNSS configuration are specified in TS 36.508 [7] subclause 4.11.
Table 7.6.2G.3.4.1-1: Test Configuration Table
|
Initial Conditions |
||||
|
Test Environment as specified in TS 36.508[7] subclause 4.1 |
Normal |
|||
|
Test Frequencies as specified in TS 36.508 [7] subclause 4.3.1 |
Low range, High range |
|||
|
Test CC Combination setting(NRB_agg) as specified in subclause 5.4.2G |
Lowest NRB_agg, Highest NRB_agg |
|||
|
Test Parameters for Channel Bandwidths |
||||
|
V2X MCC Configuration |
V2X PSSCH Allocation |
|||
|
CC1 |
CC2 |
CC1 & CC2 |
CC1 and CC2 |
|
|
50 |
50 |
QPSK |
48@2+48@2 |
|
1. Connect the SS and GNSS simulator to the UE antenna connectors as shown in TS 36.508 [7] Annex A, Figure A.92d.
2. The parameter settings for the V2X sidelink transmission over PC5 are pre-configured according to TS 36.508 [7] subclause 4.10.1. Message content exceptions are defined in clause 7.6.2G.3.4.3.
3. The V2X reference measurement channel is set according to Table 7.6.2G.3.4.1-1.
4. The GNSS simulator is configured for Scenario #1: static in Geographical area #1, as defined in TS36.508 [7] Table 4.11.2-2. Geographical area #1 is also pre-configured in the UE.
5. Propagation conditions are set according to Annex B.0.
6. Ensure the UE is in State 5A-V2X according to TS 36.508 [7] clause 4.5.9.
7. The GNSS simulator is triggered to start step 1 of Scenario #1 to simulate a location in the centre of Geographical area #1. Wait for the UE to acquire the GNSS signal and start to transmit.
7.6.2G.3.4.2 Test procedure
1. The UE starts to perform the V2X sidelink communication according to SL-V2X-Preconfiguration. Since the UE has no payload and no loopback data to send the UE sends uplink MAC padding bits on the V2X RMC.
2. Set the downlink signal level according to the table 7.6.2G.3.5-1.
3. Set the parameters of the CW signal generator for an interfering signal below the wanted signal according to Table 7.6.2G.3.5-2. The frequency step size is 1MHz.
4. Measure the average throughput for a duration sufficient to achieve statistical significance according to Annex G.2.
5. Record the frequencies for which the throughput doesn’t meet the requirements.
7.6.2G.3.4.3 Message contents
Message contents are according to TS 36.508 [7] subclause 4.6, 4.7.I and 4.10.
7.6.2G.3.5 Test Requirement
For intra-band contiguous multi-carrier operation, except for the spurious response frequencies recorded at the final step of test procedure, the throughput measurement derived in test procedure shall be ≥ 95% of the maximum throughput of the reference measurement channels as specified in clause A.3.2 with parameters specified in Tables 7.6.2G.3.5-1 and 7.6.2G.3.5-2
For Table 7.6.2G.3.5-2 in frequency range 1, 2 and 3, the number of spurious response frequencies recorded in the final step of test procedure shall not exceed 
in each assigned frequency channel when measured using a 1MHz step size. For these exceptions the requirements of subclause 7.7G spurious response are applicable.
Table 7.6.2G.3.5-1: Out-of-band blocking parameters for intra-band contiguous multi-carrier for V2X UE
|
Rx Parameter |
Units |
V2X Bandwidth Class |
||||
|
B |
C |
D |
E |
F |
||
|
Pw in Transmission Bandwidth Configuration, per CC |
dBm |
REFSENS + V2X Bandwidth Class specific value below |
||||
|
9 |
||||||
Table 7.6.2G.3.5-2: Out of band blocking for intra-band contiguous multi-carrier for V2X UE
|
V2X multi-carrier configuration |
Parameter |
Units |
Frequency |
||
|
Range 1 |
Range 2 |
Range 3 |
|||
|
PInterferer |
dBm |
-44 |
-30 |
-15 |
|
|
V2X_47B |
FInterferer (CW) |
MHz |
FDL_low -30 to FDL_low -60 |
FDL_low -60 to FDL_low -85 |
FDL_low -85 to 1 MHz |
|
FDL_high +30 to FDL_high + 60 |
FDL_high +60 to FDL_high +85 |
FDL_high +85 to +12750 MHz |
|||
|
NOTE 1: The power level of the interferer (PInterferer) for Range 3 shall be modified to -20 dBm for FInterferer > 4400 MHz. NOTE 2: The requirement is applied for 2 carrier intra-concurrent receptions when 2 carrier transmission are activated at the same time |
|||||