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OAI UE Cell sync Issue : False detection

I'm trying to synchronize the UE with eNB and found that it sometimes fail.

Setting USRP TX Freq 2560005400.000000, RX Freq 2680005400.000000

[PHY][I][UE_thread_synch] [UE thread Synch] Running Initial Synch (mode 0)

[PHY][I][init_frame_parms] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1

lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512

[PHY][I][init_frame_parms] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1

lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512

[PHY][I][initial_sync] [UE0] In synch, rx_offset 31928 samples

[PHY][I][initial_sync] [UE 0] Frame 259 RRC Measurements => rssi -73.1 dBm (dig 51.9 dB, gain 125), N0 -119 dBm, rsrp -97.9 dBm/RE, rsrq 9.0 dB

[PHY][I][initial_sync] [UE 0] Frame 259 MIB Information => FDD, NORMAL, NidCell 0, N_RB_DL 25, PHICH DURATION 0, PHICH RESOURCE 1/6, TX_ANT 1

[PHY][I][initial_sync] [UE 0] Frame 259 Measured Carrier Frequency 2680003658 Hz (offset 1742 Hz)

when scanning at around +5400 Hz from the given freq in the cmd line the UE found one cell at +3658 Hz from the cmd line. This frequency has already been scanned, this one is a false detection.

It should have found it at around + 7200 Hz.

See for reference, Pass log

Setting USRP TX Freq 2560005400.000000, RX Freq 2680005400.000000

[PHY][I][UE_thread_synch] [UE thread Synch] Running Initial Synch (mode 0)

[PHY][I][init_frame_parms] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1

lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512

[PHY][I][init_frame_parms] Initializing frame parms for N_RB_DL 25, Ncp 0, osf 1

lte_parms.c: Setting N_RB_DL to 25, ofdm_symbol_size 512

[PHY][I][initial_sync] [UE0] In synch, rx_offset 1116 samples

[PHY][I][initial_sync] [UE 0] Frame 228 RRC Measurements => rssi -73.1 dBm (dig 51.9 dB, gain 125), N0 -119 dBm, rsrp -97.8 dBm/RE, rsrq 9.0 dB

[PHY][I][initial_sync] [UE 0] Frame 228 MIB Information => FDD, NORMAL, NidCell 0, N_RB_DL 25, PHICH DURATION 0, PHICH RESOURCE 1/6, TX_ANT 1

[PHY][I][initial_sync] [UE 0] Frame 228 Measured Carrier Frequency 2680007101 Hz (offset -1701 Hz)

[HW][I][UE_thread_synch] Got synch: hw_slot_offset 0

Setting USRP TX Freq 2560007101.000000, RX Freq 2680007101.000000