Uplink synchronization timing deviation determination method and device
View Patent ↗Disclosed in the present disclosure are an uplink synchronization timing deviation determination method and device, for solving the problem in the prior art that a base station in an NB-IoT system has low accuracy in determining an uplink synchronization timing deviation by performing FFT and IDFT processing on a preamble sequence. The method specifically comprises: a base station receiving a preamble signal transmitted by a terminal device; determining channel estimation values of a frequency domain channel occupied for transmitting each symbol group of the preamble signal; performing, on the basis of a frequency hopping pattern used for transmitting the preamble signal, a conjugate multiplication on the channel estimation values corresponding to each symbol group to obtain a first radian value, and determining, on the basis of the first radian value, an uplink synchronization timing deviation of the terminal device.
1. A method of determining uplink synchronization timing deviation, comprising:
receiving, by a base station, a preamble signal transmitted by a user equipment;
determining, by the base station, a channel estimate value of a frequency-domain channel occupied by each symbol group in the preamble signal;
performing, by the base station, conjugate multiplication on the channel estimate value corresponding to each symbol group based on a frequency hopping pattern used by the preamble signal to obtain a first radian value, and determining the uplink synchronization timing deviation of the user equipment based on the first radian value;
wherein performing, by the base station, conjugate multiplication on the channel estimate value corresponding to each symbol group based on a frequency hopping pattern used by the preamble signal to obtain a first radian value, comprises:
performing, by the base station, conjugate multiplication on channel estimate values of any two symbol groups of which a frequency hopping interval is N subcarriers in the preamble signal to obtain at least two results, and obtaining a sum of the at least two results of the conjugate multiplication as a second radian value, wherein N is a positive integer;
performing, by the base station, conjugate multiplication on channel estimate values of any two symbol groups of which a frequency hopping interval is H subcarriers in the preamble signal to obtain at least two results, and obtaining a sum of the at least two results of the conjugate multiplication as a third radian value, wherein H is a positive integer and N is less than H;
obtaining, by the base station, a sum of the second radian value and the third radian value as the first radian value.
2. The method of claim 1 , wherein the uplink synchronization timing deviation meets a formula of:
TA
=
θ
s
1
N
FFT
2
π
N
+
θ
l
1
N
FFT
2
π
H
;
wherein TA represents the uplink synchronization timing deviation; θ s1 represents an angle value obtained by converting the second radian value; θ l1 represents an angle value obtained by converting the third radian value; and N FFT is the number of points of Fast Fourier Transform, FFT, for the preamble signal, wherein π is the constant π.
3. The method of claim 1 , wherein before the base station determines the uplink synchronization timing deviation of the user equipment based on the first radian value, the method further comprises:
performing, by the base station, phase compensation on an angle value obtained by converting the third radian value, wherein the angle value obtained by converting the third radian value after the phase compensation meets a formula of:
θ l2 =angle( R l ×e −j6θs2 );
wherein θ l2 represents the angle value obtained by converting the third radian value after the phase compensation; R l represents the third radian value; and θ s2 represents an angle value obtained by converting the second radian value, wherein e is the constant e.
4. The method of claim 1 , wherein receiving, by the base station, the preamble signal transmitted by the user equipment, comprises:
receiving, by the base station, preamble signals transmitted repeatedly by the user equipment;
after performing, by the base station, conjugate multiplication on the channel estimate value corresponding to each symbol group based on a frequency hopping pattern used by the preamble signal to obtain the first radian value, the method further comprises:
determining, by the base station, a first average value of first radian values of the preamble signals transmitted repeatedly, and determining the uplink synchronization timing deviation of the user equipment based on the first average value.
5. The method of claim 1 , wherein receiving, by the base station, the preamble signal transmitted by the user equipment, comprises:
receiving, by the base station, the preamble signals transmitted by the user equipment via multi-antenna;
after performing, by the base station, conjugate multiplication on the channel estimate value corresponding to each symbol group based on the frequency hopping pattern used by the preamble signal to obtain the first radian value, the method further comprises:
determining, by the base station, a second average value of the first radian values of the preamble signals transmitted via the multi-antenna, and determining the uplink synchronization timing deviation of the user equipment based on the second average value.
6. A device of determining uplink synchronization timing deviation, comprising:
a transceiver configured to receive a preamble signal transmitted by a user equipment;
a processor configured to determine a channel estimate value of a frequency-domain channel occupied by each symbol group in the preamble signal received by the transceiver, perform conjugate multiplication on the channel estimate value corresponding to each symbol group based on a frequency hopping pattern used by the preamble signal to obtain a first radian value, and determine the uplink synchronization timing deviation of the user equipment based on the first radian value;
wherein when performing conjugate multiplication on the channel estimate value corresponding to each symbol group based on a frequency hopping pattern used by the preamble signal to obtain a first radian value, the processor is configured to:
perform conjugate multiplication on channel estimate values of any two symbol groups of which a frequency hopping interval is N subcarriers in the preamble signal to obtain at least two results, and obtain a sum of the at least two results of the conjugate multiplication as a second radian value, wherein N is a positive integer;
perform conjugate multiplication on channel estimate values of any two symbol groups of which a frequency hopping interval is H subcarriers in the preamble signal to obtain at least two results, and obtain a sum of the at least two results of the conjugate multiplication as a third radian value, wherein H is a positive integer and N is less than H;
obtain a sum of the second radian value and the third radian value as the first radian value.
7. The device of claim 6 , wherein the uplink synchronization timing deviation meets a formula of:
TA
=
θ
s
1
N
FFT
2
π
N
+
θ
l
1
N
FFT
2
π
H
;
wherein TA represents the uplink synchronization timing deviation; θ s1 represents an angle value obtained by converting the second radian value; θ l1 represents an angle value obtained by converting the third radian value; and N FFT is the number of points of Fast Fourier Transform, FFT, for the preamble signal, wherein π is the constant π.
8. The device of claim 6 , wherein the processor is further configured to perform phase compensation on an angle value obtained by converting the third radian value determined before determining the uplink synchronization timing deviation of the user equipment based on the first radian value, wherein the angle value obtained by converting the third radian value after the phase compensation meets a formula of:
θ l2 =angle( R l ×e −j6θs2 );
wherein θ l2 represents the angle value obtained by converting the third radian value after the phase compensation; R l represents the third radian value; and θ s2 represents an angle value obtained by converting the second radian value, wherein e is the constant e.
9. The device of claim 6 , wherein the transceiver is configured to:
receive preamble signals transmitted repeatedly by the user equipment;
the processor is further configured to:
after performing conjugate multiplication on the channel estimate value corresponding to each symbol group based on the frequency hopping pattern used by the preamble signal to obtain the first radian value, determine a first average value of the first radian values of the preamble signals transmitted repeatedly, and determine the uplink synchronization timing deviation of the user equipment based on the first average value.
10. The device of claim 6 , wherein the transceiver is configured to:
receive the preamble signals transmitted by the user equipment via multi-antenna;
the processor is further configured to:
after performing conjugate multiplication on the channel estimate value corresponding to each symbol group based on the frequency hopping pattern used by the preamble signal to obtain the first radian value, determine a second average value of the first radian values of the preamble signals transmitted via the multi-antenna, and determine the uplink synchronization timing deviation of the user equipment based on the second average value.