| CPC H04W 56/0015 (2013.01) | 1 Claim |
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1. A data frame synchronization method in a 5G baseband processing station, using a global position system (GPS)-integrated local oscillator block controller, the method comprising the steps of:
receiving a GPS signal via a block of GPS antenna from a GPS satellite;
receiving the GPS signal, in a GPS block, from the GPS antenna and provide a 1 pps (pulse per second) pulse from a station's local oscillator block;
using the 1 pps pulse from the GPS block as reference pulse, generate a local oscillator pulse,
wherein the local oscillator pulse is supplied to a 10 ms (millisecond) counter;
wherein the local oscillator is configurable, whereby it can be operated by a parameter configuration to adjust a local oscillator frequency;
receiving, using a 10 ms counter, the local oscillator pulses from the local oscillator to generate 10 ms pulses;
monitoring, using a 10 ms synchronous plus counter, a 10 ms synchronous pulse from the 10 ms counter to calculate an error between 100 of the 10 ms pulses and 1 pps pulses, to provide the error to the local oscillator;
calculating, by a local oscillator controller, configuration parameters using the error provided from the 10 ms synchronous pulse monitor, wherein the configuration parameters are used to adjust the local oscillator block;
carry out transmission of uplink and downlink, using a TDD data frame block; wherein the block uses 10 ms synchronous pulse;
wherein the above steps are performed in the blocks above as follows:
Step 1: synchronize the baseband processor's local oscillator block with the GPS's 1 pps pulse and generate a 10 ms pulse from the local oscillator;
using the GPS 1 pps pulse as the reference input for the local oscillator block; based on the 1 pps GPS reference pulse, the local oscillator block generates an local oscillator pulse to provide other components of the 5G baseband processing station, including the 10 ms counter to generate the 10 ms pulse; after the 10 ms counter is given frequency, the counter starts to pulse from the GPS 1 pps pulse rising edge; at the rising edge of the 1 pps pulse, the counter starts counting from one and counting according to the frequency of the local oscillator; the 10 ms counter generates the next pulses from the local oscillator; when the counter reaches the value (local oscillator frequency)/100 (due to 10 ms= 1/100 s), generate a 10 ms pulse and reset the count value to one; so, after step 1, a 10 ms pulse was generated based on the local oscillator block of the baseband processing station;
Step 2: use the 10 ms synchronous pulse sync monitor block to get the synchronous offset between this pulse and the GPS 1 pps pulse;
Input of this step is the counter variable value of 10 ms counter and 1 pps GPS pulse generated from step 1; at this step, the GPS pulse 1 pps rising edge triggers the monitor to calculate the error of the 10 ms pulse; the error is calculated as the difference between the desired value of (local oscillator frequency)/100 and the counter value at the time of the 1 pps pulse rising edge; this error value is the cumulative deviation of 100 of 10 ms pulses compared to 1 second of 1 pps GPS pulses, which is also the output value of step 2; the error value will be put into a memory to be used as input for step 3;
Step 3: use a control algorithm to reconfigure the local oscillator so that the 10 ms synchronous pulse can follow the 1 pps GPS pulse;
The input to this step is the error value calculated in step 2; At this step, each time the error value is calculated and entered into the memory, the local oscillator controller relies on this error to adjust the frequency of the local oscillator pulse so that the error values of the successive times according to convergence to 0; To achieve this, the local oscillator will apply the control algorithm (which may be chosen from an on-off control algorithm or a PID proportional integral control algorithm) to calculate and adjust the frequency of the local oscillator, finally, the 10 ms pulse was synchronized to the GPS's 1 pps pulse; After adjusting the local oscillator frequency, the oscillator continues to wait for the next error value.
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