A binary baseband signal bit synchronization method

Abstract

This invention relates to the field of baseband data bit synchronization, specifically a binary baseband signal bit synchronization method. The method includes performing binary symbol determination on baseband data to obtain baseband bit data; using the ratio of the baseband bit data's sampling rate to the baseband bandwidth as the oversampling rate; calculating a midpoint based on the oversampling rate; using preset filter bits, a synchronization counter, a first missynchronization avoidance counter, and a second missynchronization avoidance counter to synchronize the baseband bit data based on the oversampling rate and the midpoint; simultaneously, performing majority decision on the baseband bit data or baseband data according to the application scenario to obtain synchronization bit data; and using the synchronization bit data as the bit synchronization result for the binary baseband. This method simplifies existing self-synchronization methods; due to the simplified algorithm, it achieves lower hardware costs and lower power consumption, making it more suitable for the Internet of Things (IoT).

Description

Technical Field

[0001] This invention generally relates to the field of baseband data bit synchronization, and more specifically, to a binary baseband signal bit synchronization method. Background Technology

[0002] Existing binary baseband signal bit synchronization algorithms are mainly divided into two categories: external synchronization method (pilot insertion method) and self-synchronization method (direct method). Among them, the external synchronization method (pilot insertion method) includes: (1) direct pilot insertion: the transmitter inserts a pilot signal of a specific frequency into the digital signal, and the receiver extracts the synchronization information through a narrowband filter; (2) double modulation pilot insertion: the modulated signal is subjected to secondary amplitude modulation, and the modulation signal is the synchronization signal, which is extracted by the receiver through envelope detection; (3) separate channel transmission: the synchronization signal is transmitted through an independent channel, which is simple to implement but has low resource utilization. The self-synchronization method (direct method) includes: (1) filtering method: 1) differential full-wave rectification method, the baseband signal is differentially rectified and then filtered to extract the synchronization component; 2) squaring method, the timing component is generated through square nonlinear transformation; 3) delay coherence method: the signal is multiplied by delay and then filtered. (2) Phase-locked loop (phase comparison method): 1) Gardner algorithm: adjusts the phase of the local clock by interpolation and timing error detection, suitable for digital implementation; 2) Lead / lag gate synchronizer: compares the phase difference between the received signal and the local timing signal for closed-loop adjustment.

[0003] However, existing binary baseband signal bit synchronization algorithms still have defects. The disadvantages of the external synchronization method (pilot insertion method) are as follows: (1) It requires additional bandwidth to transmit pilot signals, reducing spectrum utilization; (2) The pilot signal occupies part of the transmission power, which may affect the quality of the main signal; (3) The synchronization reliability is highly dependent on the stability of the pilot transmission link, and channel distortion may lead to synchronization failure. The disadvantages of the self-synchronization method (direct method) are as follows: (1) High implementation complexity: It requires the design of phase-locked loops, interpolation control and other modules, and the complexity of hardware circuits or digital algorithms is significantly higher than that of the external synchronization method; (2) Longer setup time: It depends on the statistical characteristics of data, and the synchronization acquisition speed is usually slower than that of the external synchronization method. Summary of the Invention

[0004] According to the present invention, a binary baseband signal bit synchronization method is provided. This solution simplifies existing self-synchronization methods; due to the simplified algorithm, it achieves lower hardware cost and lower power consumption, making it more suitable for the Internet of Things (IoT).

[0005] In a first aspect of the present invention, a binary baseband signal bit synchronization method is provided. The method includes: Acquiring baseband data and application scenarios for baseband data; Perform binary sign determination on the baseband data to obtain baseband bit data; The ratio of the baseband bit data sampling rate to the baseband bandwidth is used as the oversampling rate; and the midpoint of the count is calculated based on the oversampling rate. Based on the oversampling rate and the midpoint of the count, the baseband bit data is counted and synchronized using preset filter bits, synchronization counters, a first missynchronization avoidance counter, and a second missynchronization avoidance counter; while counting and synchronizing, the baseband bit data or baseband data is subject to majority decision based on the application scenario of the baseband data to obtain synchronization bit data; The synchronization bit data is used as the result of binary baseband signal bit synchronization.

[0006] Furthermore, the step of using preset filter bits, synchronization counters, a first missynchronization avoidance counter, and a second missynchronization avoidance counter to count and synchronize the baseband bit data includes: Iterate through all bits in the baseband bit data; The synchronization conditions for each bit of data are set based on the filter bit, the synchronization counter, the first missynchronization avoidance counter, and the second missynchronization avoidance counter. The synchronization counter is adjusted based on the synchronization conditions of each bit of data.

[0007] Furthermore, synchronization conditions include: The first synchronization condition is that the bit data is not equal to the filtered bit. The second synchronization condition is that if the oversampling rate is not less than the third oversampling rate threshold, the bit data is the same as the N bits following it; if the oversampling rate is not less than the first oversampling rate threshold and less than the third oversampling rate threshold, the bit data is the same as the M bits following it. The third synchronization condition is that the first condition is to avoid missynchronization. The counter's count data must equal the oversampling rate. The fourth synchronization condition is that the count data of the synchronization counter equals the midpoint of the count; The fifth synchronization condition is that the oversampling rate is odd and the count data of the synchronization counter is equal to the midpoint of the count plus one. The sixth synchronization condition is that the count data of the second anti-missynchronization counter is equal to Z; where Z is a value set according to the oversampling rate.

[0008] Furthermore, the step of adjusting the synchronization counter according to the synchronization condition of each bit of data includes: The synchronization counter performs its first count based on the synchronization condition. Perform a second count on the synchronous counter following the first count; The step of performing a first count on the synchronization counter according to the synchronization condition includes: When the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met: if the count data of the synchronization counter is less than the midpoint of the count, then when the count data of the synchronization counter is not greater than the first threshold, the count data of the synchronization counter is cleared to zero; when the count data of the synchronization counter is greater than the first threshold, the difference between the count data of the synchronization counter and the result of dividing the count data of the synchronization counter by 2 and taking the integer value is used as the count data of the synchronization counter. When the first, second, and third synchronization conditions are all met, if the fourth or fifth synchronization condition is met, the count data of the synchronization counter is incremented by one when the sixth synchronization condition is met; if the sixth synchronization condition is not met, the count data of the synchronization counter remains unchanged. If neither the fourth nor the fifth synchronization condition is met and the count data of the synchronization counter is greater than the midpoint of the count, the count data of the synchronization counter is cleared to zero when the count data of the synchronization counter is equal to the oversampling rate minus 1; if the count data of the synchronization counter is not equal to the oversampling rate minus 1, the count data of the synchronization counter is calculated based on the oversampling rate. The second counting of the synchronization counter includes: if the count data of the synchronization counter is less than the oversampling rate minus 1, then increment the count data of the synchronization counter by 1; otherwise, clear the count data of the synchronization counter to zero.

[0009] Furthermore, before performing the second count on the synchronization counter, the second missynchronization avoidance counter, the first missynchronization avoidance counter, and the filter bit are adjusted sequentially to set the synchronization condition for the next bit of baseband bit data. Adjusting the second synchronization avoidance counter includes: when the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met: if the fourth or fifth synchronization condition is met and the sixth synchronization condition is not met, then increment the count data of the second synchronization avoidance counter by 1; if neither the fourth nor the fifth synchronization condition is met, or the sixth synchronization condition is met, then clear the count data of the second synchronization avoidance counter to zero. Adjusting the first synchronization avoidance counter includes: if the third synchronization condition is not met, incrementing the count data of the first synchronization avoidance counter by 1; if the third synchronization condition and the first synchronization condition are met and the second synchronization condition is not met, setting the count data of the first synchronization avoidance counter to 1; otherwise, keeping the count data of the first synchronization avoidance counter unchanged. The filter bit is adjusted as follows: if the first synchronization condition is met and the second synchronization condition is not met, the filter bit is equal to the inverted bit data; if both the first and second synchronization conditions are met, the filter bit is equal to the bit data; otherwise, the filter bit remains unchanged.

[0010] Furthermore, before setting the synchronization conditions for each bit of data, the following is also included: If the count data of the synchronization counter is equal to the midpoint of the count, then the baseband bit data or baseband data is subject to majority voting based on the application scenario of the baseband data to obtain the synchronization bit data.

[0011] Furthermore, the majority decision-making process for baseband bit data or baseband data based on the application scenario of the baseband data includes: The decision parameters are set based on the oversampling rate and the second oversampling threshold; The decision threshold is set according to the decision parameters and the application scenario of the baseband data: if the application scenario of the baseband data is an IoT system, the decision threshold is equal to the decision parameters; if the application scenario of the baseband data is a non-IoT system, the decision threshold is set to 0. The decision sum is calculated based on the baseband bit data, baseband data, and the application scenario of the baseband data: If the application scenario of the baseband data is an IoT system, the decision sum is calculated based on the baseband bit data when the synchronization counter equals the midpoint of the count; if the application scenario of the baseband data is a non-IoT system, the decision sum is calculated based on the baseband data when the synchronization counter equals the midpoint of the count. If the decision sum is not greater than the decision threshold, the output synchronization bit data is 0; otherwise, the output synchronization bit data is 1.

[0012] Furthermore, the decision parameters for setting the oversampling rate and the second oversampling rate threshold include: if the oversampling rate is not less than the first oversampling rate threshold and is less than the second oversampling rate threshold, then the decision parameters are calculated based on the oversampling rate; if the oversampling rate is not less than the second oversampling rate threshold, then the decision parameters are calculated based on the second oversampling rate threshold. The calculation of the decision parameters based on the oversampling rate includes: The calculation of the decision parameters based on the second oversampling rate threshold includes: Where X is a preset value; Floor is the floor function.

[0013] Further, the calculation of the decision sum based on the baseband bit data includes: The sum of the current bit data, the first K bits of the current bit data, and the last K bits of the current bit data in the baseband bit data is used as the decision sum; where K is the decision parameter.

[0014] Furthermore, the calculation of the decision sum based on baseband data includes: The sum of the current baseband data, the K baseband data preceding the current baseband data, and the K baseband data following the current baseband data is used as the decision sum; where K is the decision parameter.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: Using a counting-based synchronization method to synchronize binary baseband signal bits is an algorithm that uses fewer resources and consumes less power. Compared to the Gardner bit synchronization algorithm, it does not require complex multiplication, thus reducing hardware area and power consumption. It should be understood that the description in this summary is not intended to limit the key or essential features of the embodiments of the invention, nor is it intended to restrict the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0016] The above and other features, advantages, and aspects of the various embodiments of the present invention will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: Figure 1 A flowchart of a binary baseband signal bit synchronization method according to an embodiment of the present invention is shown; Figure 2 A flowchart illustrating baseband bit data counting synchronization according to an embodiment of the present invention is shown; Figure 3 A flowchart of synchronous counter count adjustment according to an embodiment of the present invention is shown; Figure 4 A flowchart illustrating the majority decision-making process according to an embodiment of the present invention is shown; Figure 5 The following diagram shows waveforms of baseband data and baseband bit data according to an embodiment of the present invention; Figure 6 Waveform diagrams of a synchronization counter, a first missynchronization avoidance counter, and a filter bit according to an embodiment of the present invention are shown; Figure 7 The output waveform diagram of bit synchronization according to an embodiment of the present invention is shown; in, Figure 5 In the diagram: a is the sampling time; b is the decision threshold; c is the synchronization value of the synchronization count; d is the sampling time; e is the binary baseband bit; f is the baseband data; g is the binary baseband bit converted from the baseband data above after binary symbol decision. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0019] In this invention, binary symbol determination is performed on the baseband data to obtain baseband bit data; the baseband bit data is then synchronized by counting; simultaneously with the counting synchronization, a majority decision is made on the baseband bit data or baseband data based on the application scenario to obtain synchronization bit data; and the synchronization bit data is used as the result of binary baseband signal bit synchronization. This method reduces hardware area and power consumption.

[0020] Example 1 Figure 1 A flowchart of a binary baseband signal bit synchronization method according to an embodiment of the present invention is shown.

[0021] The method includes S101~S105: S101. Acquiring baseband data and application scenarios of baseband data.

[0022] S102. Perform binary symbol determination on the baseband data to obtain baseband bit data. The baseband bit data is single-bit data.

[0023] Specifically, binary sign decision refers to: performing sign decision on binary baseband data (assuming that the binary baseband data has no DC component and the decision threshold = 0). If the baseband data is greater than the decision threshold, the decision is 1; otherwise, the decision is 0.

[0024] As some optional implementations of this embodiment, the baseband data and baseband bit data are as follows: Figure 5 As shown, baseband data is processed by binary symbol decision to obtain binary baseband bits. If the baseband data is greater than the decision threshold (assuming the binary baseband data has no DC component, decision threshold = 0), the obtained bit is 1; otherwise, it is 0. Each symbol is sampled 8 times, so the oversampling is equal to 8.

[0025] S103. The ratio of the baseband bit data sampling rate to the baseband bandwidth is used as the oversampling rate; and the midpoint of the count is calculated based on the oversampling rate.

[0026] Specifically, the formula for calculating the oversampling rate is: The formula for calculating the midpoint of the count is: ,in This is the floor function.

[0027] S104. Based on the oversampling rate and the midpoint of the count, the baseband bit data is counted and synchronized using preset filter bits, a synchronization counter, a first missynchronization avoidance counter, and a second missynchronization avoidance counter. Simultaneously with the counting synchronization, a majority decision is made on the baseband bit data or baseband data based on the application scenario of the baseband data to obtain synchronization bit data.

[0028] Specifically, when counting and synchronizing each bit in the baseband bit data, it is determined whether the majority decision condition is met. If it is met, the majority decision is made on the baseband bit data or baseband data according to the application scenario of the baseband data, and the majority decision result, i.e., the synchronization bit data, is output.

[0029] In this embodiment, as Figure 2 As shown, the step of using preset filter bits, synchronization counters, a first missynchronization avoidance counter, and a second missynchronization avoidance counter to count and synchronize the baseband bit data includes steps S201~S202: S201. Traverse all bit data in the baseband bit data.

[0030] S202. Set the synchronization conditions for each bit of data based on the filter bit, synchronization counter, first missynchronization avoidance counter and second missynchronization avoidance counter.

[0031] In this embodiment, the synchronization conditions are the following six synchronization conditions: (1) First synchronization condition: bit data is not equal to filter bit.

[0032] (2) Second synchronization condition: If the oversampling rate is not less than the third oversampling rate threshold, the bit data is the same as the N bits following it; if the oversampling rate is not less than the first oversampling rate threshold and less than the third oversampling rate threshold, the bit data is the same as the M bits following it. N can be: oversampling rate - 3, M can be: third oversampling rate threshold - 3, and the third oversampling rate threshold can be 9; (3) The third synchronization condition is that the count data of the first synchronization avoidance counter is equal to the oversampling rate.

[0033] (4) Fourth synchronization condition: the counting data of the synchronization counter is equal to the midpoint of the count.

[0034] (5) The fifth synchronization condition is that the oversampling rate is odd and the counting data of the synchronization counter is equal to the midpoint of the count plus one.

[0035] (6) The sixth synchronization condition is that the count data of the second anti-missynchronization counter is equal to Z. When the oversampling rate is equal to 5, Z can be 63; when the oversampling rate is equal to 6, Z can be 15; otherwise, Z can be 7.

[0036] The following advantages are achieved by setting the above six synchronization conditions for subsequent judgment: (1) The filtered bit changes only when the bit data is stable. The second synchronization condition monitors whether there is interference and noise. The third synchronization condition shields the detected interference and noise for a period of time. Therefore, the first, second and third synchronization conditions will shield the influence of interference and noise and perform synchronous counting (first counting) as much as possible when there is no interference. (2) The fourth or fifth synchronization condition is when the synchronization counter counts to the midpoint of the binary symbol bit. When the oversampling rate is relatively small, the phase fluctuation caused by noise or interference may cause the phase lock of the synchronization counter to be lost. The purpose of setting the sixth synchronization condition is to overcome the phase lock of the synchronization counter caused by the phase fluctuation of the binary bit data due to noise or interference when the first, second and third synchronization conditions and the fourth or fifth synchronization conditions are met. The effect is more obvious when the oversampling rate is relatively small.

[0037] like Figure 3 As shown, the synchronization counter is adjusted according to the synchronization condition of each bit of data, including S301~S302: S301. Perform the first count on the synchronization counter according to the synchronization condition, including: When the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met: (First branch) If the count data of the synchronization counter is less than the midpoint of the count, then when the count data of the synchronization counter is not greater than the first threshold, the count data of the synchronization counter is cleared to zero. When the count data of the synchronization counter is greater than the first threshold, the difference is used as the count data of the synchronization counter, where the difference is the difference between the count data of the synchronization counter and FLoor(count data of the synchronization counter / 2).

[0038] (Second Branch) When the first, second, and third synchronization conditions are all met, if the fourth or fifth synchronization condition is met, then when the sixth synchronization condition is met, the count data of the synchronization counter is incremented by one; if the sixth synchronization condition is not met, the count data of the synchronization counter remains unchanged. (Third Branch) If neither the fourth nor the fifth synchronization condition is met and the count data of the synchronization counter is greater than the midpoint of the count, then when the count data of the synchronization counter is equal to the oversampling rate minus 1, the count data of the synchronization counter is cleared to zero; if the count data of the synchronization counter is not equal to the oversampling rate minus 1, the count data of the synchronization counter is calculated based on the oversampling rate.

[0039] Specifically, the calculation of the synchronization counter's count data based on the oversampling rate includes: .

[0040] As some optional implementations of this embodiment, assuming the oversampling rate O=8, the maximum value of the synchronization counter: Cmax=O−1=7; the counting midpoint: taking the symmetrical midpoint, M= (O / 2) = 4; First threshold T1 = 1; When the first synchronization condition, the second synchronization condition, and the third synchronization condition are all satisfied, the following example is given: (1) When the count data of the synchronous counter is c=1, the first branch judgment is performed: 1<4 (satisfies less than the midpoint of the count), the first branch is executed, and since 1≤1 (equal to the first threshold), the count data of the synchronous counter is directly cleared to zero.

[0041] (2) When the count data of the synchronous counter is c=2, the first branch judgment is performed: 2<4, the condition is met and the first branch is executed; since 2>1, the count data of the synchronous counter is c=2−Floor(2 / 2)=1.

[0042] (3) When the count data of the synchronization counter c=4, the first branch judgment is performed: 4<4 is not true, so the first branch is not executed; the second branch judgment is performed: if the fourth synchronization condition or the fifth synchronization condition is met, the second branch is executed; when the sixth synchronization condition is met... =4+1=5, when the sixth synchronization condition is not met. =4.

[0043] (4) When the count data of the synchronization counter is c=5, the first branch judgment is performed: 5<3 is not true, so the first branch is not executed; the second branch judgment is performed: if neither the fourth synchronization condition nor the fifth synchronization condition is satisfied, the second branch is not executed; if neither the first branch judgment nor the second branch judgment is true, the third branch is executed, and 5 is not equal to (8-1). .

[0044] (5) When the count data of the synchronization counter is c=7, the first branch judgment is performed: 7<4 is not true, so the first branch is not executed; the second branch judgment is performed: the fourth synchronization condition and the fifth synchronization condition are not satisfied, so the second branch is not executed; then the third branch is executed: the count data of the synchronization counter It equals (8-1). .

[0045] S302. Perform a second count on the synchronization counter after the first count, including: if the count data of the synchronization counter is less than the oversampling rate minus 1, then increment the count data of the synchronization counter by 1; otherwise, clear the count data of the synchronization counter to zero.

[0046] By performing the first count of the synchronization counter, the value of the synchronization counter is adjusted to synchronize with the binary baseband signal. After synchronization is completed, it is equal to the starting point of the binary baseband symbol corresponding to the number 0, and it is equal to the ending point of the binary baseband symbol corresponding to the number "oversampling rate - 1". By performing the second count of the synchronization counter, the next bit is taken as the "new" current bit.

[0047] In this embodiment, before performing the second count on the synchronization counter, the second missynchronization avoidance counter, the first missynchronization avoidance counter, and the filter bit are adjusted sequentially to set the synchronization condition for the next bit of baseband bit data.

[0048] In this embodiment, adjusting the second synchronization avoidance counter includes: when the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met: if the fourth synchronization condition or the fifth synchronization condition is met and the sixth synchronization condition is not met, then the count data of the second synchronization avoidance counter is incremented by 1; if the fourth synchronization condition and the fifth synchronization condition are not met, or the sixth synchronization condition is met, then the count data of the second synchronization avoidance counter is cleared to zero.

[0049] Specifically, if the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met, then the second synchronization avoidance counter is adjusted; otherwise, the second synchronization avoidance counter is not adjusted. The adjustment of the second synchronization avoidance counter includes: (1) If the fourth or fifth synchronization condition is met and the sixth synchronization condition is not met, then the count data of the second anti-missynchronization counter is incremented by 1.

[0050] (2) If the fourth and fifth synchronization conditions are not met, or the sixth synchronization condition is met, then the count data of the second anti-missynchronization counter is cleared.

[0051] In this embodiment, adjusting the first synchronization avoidance counter includes: if the third synchronization condition is not met, incrementing the count data of the first synchronization avoidance counter by 1; if the third synchronization condition and the first synchronization condition are met and the second synchronization condition is not met, setting the count data of the first synchronization avoidance counter to 1; otherwise, keeping the count data of the first synchronization avoidance counter unchanged.

[0052] In this embodiment, adjusting the filter bit includes: if the first synchronization condition is met and the second synchronization condition is not met, then the filter bit is equal to the inverted bit data; if both the first and second synchronization conditions are met, then the filter bit is equal to the bit data; otherwise, the filter bit remains unchanged.

[0053] As some optional implementations of this embodiment, the waveforms of the synchronization counter, the first missynchronization avoidance counter, and the filter bit are as follows: Figure 6 As shown, the blue line represents binary bits (baseband bits), the green line represents filter bits, the red line represents the synchronization count value, and the black line represents the first synchronization avoidance count. The oversampling rate is equal to 8. Positions 4, 5, and 8 are bit flips caused by interference or noise. The specific waveform description is as follows: (1) At positions 1, 2, and 6: the baseband bit is not equal to the filter bit. The current bit and the next 5 bits are the same. The first synchronization avoidance count value is equal to the oversampling rate of 8. The first, second, and third synchronization conditions of counting synchronization are met, and the first count needs to be performed. Here, the synchronization count value is equal to 1 (the second point from 0), which is less than the midpoint of the count floor (oversampling rate / 2) = 4. According to the algorithm, the synchronization count value is set to 0. Then, in the next baseband bit, its value is less than "oversampling rate - 1", so it will increment by one, and the result is equal to 1. Therefore, the synchronization counter maintains two sampling rate periods of 1, which makes the counting start point of the synchronization counter close to the transition edge of the current bit. That is, synchronization is achieved.

[0054] (2) At position 3: The baseband bit is not equal to the filter bit. The current bit and the next 5 bits are all 0. The first synchronization avoidance count value is equal to the oversampling rate of 8. The first synchronization condition, the second synchronization condition, and the third synchronization condition are met, and the first count needs to be performed. Here, the synchronization count value is equal to 7 (the 8th point starting from 0), which is greater than the midpoint of the count floor (oversampling rate / 2) = 4. According to the algorithm, the synchronization count value is set to 0. Then, in the next baseband bit, its value is less than "oversampling rate - 1", so it will increment by one, and the result is equal to 1. Therefore, the synchronization counter changes from the number 7 to the number 1, which brings the starting point of the synchronization counter closer to the transition edge of the current bit. That is, synchronization is achieved.

[0055] (3) At positions 4 and 7: the baseband bit is not equal to the filter bit. The current bit and the next 5 bits are not the same. The first avoidance of synchronization count value is equal to the oversampling rate 8. The second synchronization condition of the count synchronization is not met, so the first count is not performed. The synchronization counter value is equal to 7. When the next bit arrives, its value is not less than "oversampling rate - 1", so it is cleared to zero, and the result is equal to 0. So the synchronization count value changes from the number 7 to the number 0. Because the first synchronization condition of the count synchronization is met, the second synchronization condition is not met, and the third synchronization condition is met (these 3 conditions are used as the conditions for the first avoidance of synchronization counter to be set to 1), the first avoidance of synchronization counter will be set to 1. During the next 8 sampling rates, the first avoidance of synchronization counter does not meet the condition for the first avoidance of synchronization counter to be set to 1, so the first avoidance of synchronization counter will count to the oversampling rate 8. Because the first synchronization condition of the count synchronization is met, and the second synchronization condition is not met (these 2 conditions are used as the conditions for the filter bit to be updated to the inverted current bit), the filter bit is equal to the inverted current bit, that is, it remains unchanged.

[0056] (4) At positions 5 and 8: the baseband bit is not equal to the filter bit. The current bit and the next 5 bits are not all the same. The first avoidance of synchronization counter value is not equal to the oversampling rate 8. No first count is performed. The condition for the first avoidance of synchronization counter to be set to 1 is not met, and the first avoidance of synchronization counter is less than the oversampling rate 8, so the first avoidance of synchronization counter increments by one in the subsequent bits. Because the first synchronization condition for counting synchronization is met, and the second synchronization condition is not met, the filter bit is equal to the inverse of the current bit, that is, it remains unchanged. Thus, the first count shielding for bit flipping caused by interference and noise is performed for synchronization counting.

[0057] For the second synchronization avoidance counter: when the first, second, and third synchronization conditions are met, and the fourth or fifth synchronization condition is also met, a threshold is set for adjusting the synchronization counter. This can shield the phase fluctuations caused by noise or interference from affecting the synchronization count (first count); the effect is particularly noticeable when the oversampling rate is relatively low. For the first synchronization avoidance counter: when an error of bit flipping caused by interference or noise is encountered, a time threshold is set so that the synchronization counter stops performing the first count within this time period; this shields against synchronization errors caused by noise or interference. For filtered bits: when an error of bit flipping caused by interference or noise is encountered, the synchronization counter stops performing the first count; this shields against synchronization errors caused by noise or interference.

[0058] In this embodiment, before setting the synchronization conditions for each bit of data, the method further includes: if the count data of the synchronization counter is equal to the midpoint of the count, then the baseband bit data or baseband data is decided by majority vote according to the application scenario of the baseband data to obtain the synchronization bit data.

[0059] By using majority voting to determine the sign of the output bits, the bit error rate caused by interference or noise can be effectively reduced.

[0060] In this embodiment, as Figure 4 As shown, the majority decision-making process for baseband bit data or baseband data based on the application scenario of the baseband data includes S401~S403: S401. Set decision parameters based on oversampling rate and second oversampling rate threshold, including: if the oversampling rate is not less than the first oversampling rate threshold and less than the second oversampling rate threshold, then calculate decision parameters based on the oversampling rate; if the oversampling rate is not less than the second oversampling rate threshold, then calculate decision parameters based on the second oversampling rate threshold.

[0061] The calculation of the decision parameters based on the oversampling rate includes: The calculation of the decision parameters based on the second oversampling rate threshold includes: Where X is a preset value; Floor is the floor function.

[0062] Specifically, the first oversampling rate threshold can be 5, the second oversampling rate threshold can be 9, and X can be 3.

[0063] S402. Set the decision threshold according to the decision parameters and the application scenario of the baseband data: If the application scenario of the baseband data is an IoT system, the decision threshold is equal to the decision parameters; if the application scenario of the baseband data is a non-IoT system, the decision threshold is set to 0.

[0064] As some optional implementation methods of this embodiment, the decision parameters can be set directly after the oversampling rate is obtained.

[0065] When the oversampling rate is small (greater than the first oversampling rate threshold and less than the second oversampling rate threshold), the baseband bit data or baseband data is fully utilized for majority decision-making to reduce the bit error rate. When the oversampling rate is large (greater than or equal to the second oversampling rate threshold), the decision parameters are calculated by balancing hardware resources and bit error rate results (the overhead of calculating the decision sum is limited, but the performance loss is very small).

[0066] S403. Calculate the decision sum based on the baseband bit data, baseband data, and baseband data application scenario: If the baseband data application scenario is an IoT system, then calculate the decision sum based on the baseband bit data when the synchronization counter equals the midpoint of the count; if the baseband data application scenario is a non-IoT system, then calculate the decision sum based on the baseband data when the synchronization counter equals the midpoint of the count.

[0067] In this embodiment, the step of calculating the decision sum based on the baseband bit data includes: taking the current bit data, the sum of the first K bits of the current bit data, and the sum of the last K bits of the current bit data as the decision sum; where K is the decision parameter.

[0068] As some optional implementations of this embodiment, it is assumed that the baseband bit data =1+0+1+1+0+1+0=4, K=2, oversampling rate=7, the calculation process of the decision sum is as follows: (1) Decision parameter = Floor((7-3) / 2)) = 2.

[0069] (2) Judgment sum = 0 + 1 + 1 + 0 + 1 = 3.

[0070] When using tag chips in IoT systems, the binary baseband bit data is obtained through analog circuit decision-making, and there is no corresponding binary baseband data. Therefore, majority decision-making can only be performed using the binary baseband bit data.

[0071] In this embodiment, the step of calculating the decision sum based on the baseband data includes: taking the sum of the current baseband data, the K baseband data preceding the current baseband data, and the K baseband data following the current baseband data as the decision sum; where K is the decision parameter.

[0072] As some optional implementation methods in this embodiment, it is assumed that the baseband data =1.2+(-0.5)+0.9+1+(-0.8)+0.6+1.1=3.5, K=3, oversampling rate=9, the calculation process of the decision sum is as follows: (1) Decision parameter = Floor((9-3) / 2)) = 3.

[0073] (2) Judgment sum = 1.2 + (-0.5) + 0.9 + 1 + (-0.8) + 0.6 + 1.1 = 3.5.

[0074] In non-IoT systems, binary baseband bit data has corresponding binary baseband data. Using binary baseband data for majority decision-making can reduce the bit error rate.

[0075] If the decision sum is not greater than the decision threshold, the S404 outputs a synchronization bit data of 0; otherwise, it outputs a synchronization bit data of 1.

[0076] The majority decision uses data from multiple midpoints of the count to make a binary symbol decision based on the majority, which can more accurately recover the binary synchronization signal in environments with interference or noise.

[0077] As some optional implementation methods of this embodiment, such as Figure 7 The bit synchronization output diagram is shown below. The blue line represents binary bits (baseband bits), the green line represents filter bits, the red line represents the synchronization count value, the black line represents the first count to avoid false synchronization, and the orange line represents the synchronization bit output. The oversampling rate is equal to 8, and the midpoint of the count is floor(oversampling rate / 2)=4. At positions 1, 2, 3, 4, 5, 6, and 7, the synchronization counter equals the midpoint of the count, 4, and outputs the bit synchronization signal. For example, at position 5, according to the algorithm, the "decision threshold" equals floor((8-3) / 2)=2, and the "decision sum" equals the sum of the current bit and the two bits before and after it. Figure 7 As can be seen from the data, at position 5, the sum of the current bit and the two bits before and after it is 4, that is, the "judgment sum" is equal to 4; since the "judgment sum" is greater than or equal to the "judgment threshold", the bit synchronization output at position 5 is 1.

[0078] S105. The synchronization bit data is used as the bit synchronization result of the binary baseband.

[0079] Example 2 Assume that this synchronizer needs to process data rates that are 5 times or more of the baseband symbol rate (oversampling rate), such as 5, 6, 7, 8, etc. The specific invention is as follows: Step 1: Processing baseband bit data is the single-bit data of baseband data after symbol decision.

[0080] Step 2: Calculate the oversampling rate, denoted by O.

[0081] Step 3: Use a synchronization counter (initial value 0) to count and synchronize the baseband bit data. The counter range is from 0 to 0-1.

[0082] Step 4: Calculate the midpoint of the count, midpoint = Floor(0 / 2).

[0083] Step 5: Calculate the decision parameters. Let the first oversampling rate threshold be A (A=5), the second oversampling rate threshold be B, and the third oversampling rate threshold be [missing information]. If O≥A and <B, the decision parameter K=Floor((O-3) / 2); if O≥B, the decision parameter K=Floor((B-3) / 2).

[0084] Step 6: Set the decision threshold: (1) When the application scenario is the Internet of Things, the decision threshold = decision parameter = K.

[0085] (2) When the application scenario is not the Internet of Things, the decision threshold is 0.

[0086] Step 7: Calculate the decision sum: (1) When the “synchronization counter” equals the “midpoint of the count”, calculate the decision sum.

[0087] (2) When the application scenario is the Internet of Things: the decision sum is equal to the sum of the current baseband bit data and the K baseband bit data before and after.

[0088] (3) When the application scenario is not the Internet of Things: the decision sum is equal to the sum of the current baseband data and the K baseband data before and after.

[0089] Step 8: Bit synchronization output: When the "synchronization counter" equals the "midpoint of the count", if the "judgment sum" is less than or equal to the "judgment threshold", the bit synchronization output is 0; otherwise, it outputs 1.

[0090] Step 9: Set the synchronization conditions for the synchronization counter (1) First synchronization condition: The current bit is not equal to the "filter bit" (the initial value is equal to the baseband bit value when the communication receiver is in idle state).

[0091] (2) Second synchronization condition: If O≥C, the current bit and the next C-3 bits are the same; if O≥A and O<C, the current bit and the next O-3 bits are the same.

[0092] (3) Third synchronization condition: “Avoid erroneous synchronization counter one” (initial value is 0) equals 0.

[0093] (4) Fourth synchronization condition: "Synchronization counter" equals "counting midpoint".

[0094] (5) Fifth synchronization condition: If O is odd, the "synchronization counter" is equal to the "midpoint of the count" plus one. Otherwise, if O is even, this condition is false.

[0095] (6) Sixth synchronization condition: If “avoiding false synchronization counter two” equals Z (Z≥0. For example: when O=5, Z=63; when O=6, Z=7; otherwise, Z=3).

[0096] Step 10: Adjust the synchronization counter (first count).

[0097] (1) If the first synchronization condition, the second synchronization condition and the third synchronization condition are all met, the synchronization counter will be adjusted.

[0098] (2) If the synchronization counter is less than the midpoint of the count: If the synchronization counter is less than or equal to 1, clear the synchronization counter; otherwise, decrease the synchronization counter by half (half of the synchronization counter is equal to the synchronization counter divided by 2 and rounded down).

[0099] (3) If the fourth or fifth synchronization condition is met: If the sixth synchronization condition is met, increment the synchronization counter by one; If the sixth synchronization condition is not met, keep the synchronization counter value unchanged.

[0100] (4) Otherwise: If the synchronization counter is equal to O-1, clear the synchronization counter; otherwise, increment the synchronization counter by half the difference between the synchronization counter and O (half the difference between the synchronization counter and O = Floor((O-synchronization counter value) / 2)).

[0101] Step 11: Adjust the anti-synchronization counter 2: When the first, second, and third synchronization conditions are all met, the fourth or fifth synchronization condition is met, and the sixth synchronization condition is not met, increment the anti-synchronization counter 2 by one. Otherwise, when the first, second, and third synchronization conditions are all met, the fourth and fifth synchronization conditions are not met, or the sixth synchronization condition is met, reset the anti-synchronization counter 2 to zero.

[0102] Step 12: Adjust the avoidance of synchronization counter 1: If the third synchronization condition is not met, increment the avoidance of synchronization counter 1 by one; otherwise, if the first synchronization condition is met but the second synchronization condition is not met, set the avoidance of synchronization counter 1 to 1; otherwise, keep the value of the avoidance of synchronization counter 1 unchanged.

[0103] Step 13: Adjust the filter bit: If the first synchronization condition is met and the second synchronization condition is not met, the filter bit is equal to the inverted value of the current bit; if the first synchronization condition is met and the second synchronization condition is met, the filter bit is equal to the current bit; otherwise, keep the value of the filter bit unchanged.

[0104] Step 14: Adjust the synchronization counter: If the synchronization counter is less than 0-1, increment the synchronization counter by 1; otherwise, the synchronization counter is equal to 0.

[0105] Step 15: Traverse all baseband bit data, and iteratively execute steps 7 to 14 for each baseband bit data.

[0106] According to embodiments of the present invention, the following advantages are available compared to the prior art: (1) Achieve extremely low hardware cost and low power consumption. Traditional algorithms (such as filtering methods and Gardner rings) use filters and multipliers, which are not suitable for passive IoT chip applications because their area and power consumption exceed the requirements of passive IoT chips. In contrast, this invention mainly uses counting synchronization, which has very low area and power consumption.

[0107] (2) Fast and stable synchronization acquisition. The first count of the synchronization counter of the present invention adopts a method of moving half the distance to the ideal synchronization point each time; in this way, synchronization acquisition can be achieved quickly and the influence of noise or interference on the counting synchronization can be effectively resisted.

[0108] (3) Better performance. This invention can filter out the signal inversion caused by interference or noise, and perform counting synchronization when the signal is stable, thus improving the anti-interference and noise capability. The output is judged by multiple bits, improving the accuracy of the output. Performance comparison with the traditional Gardner bit synchronization algorithm (assuming the oversampling rate is equal to 8). The bit error rate of the traditional Gardner bit synchronization algorithm is shown in Table 1, and the bit synchronization algorithm of this invention is shown in Table 2 (most decisions use baseband data) and Table 3 (most decisions use baseband bit data). It can be seen from the above three tables that the algorithm of this invention has better performance.

[0109] Table 1 Serial Number Signal-to-noise ratio (dB) Total number of symbols Error count Bit error rate (‰) illustrate 1 7 383979 1980 5.156531998 2 7.5 383979 1304 3.396019053 3 8 383979 770 2.005317999 4 8.5 383979 440 1.145896 5 9 383979 282 0.734415163 6 9.5 383979 127 0.330747254 7 10 383979 55 0.143237 8 10.5 383979 28 0.072920655 9 11 383979 10 0.026043091 10 11.5 383979 5 0.013021545 11 12 383979 1 0.002604309 12 12.5 383979 0 0 13 13 383979 0 0 14 13.5 383979 0 0 15 14 383979 0 0 Table 2 Serial Number Signal-to-noise ratio (dB) Total number of symbols Error count Bit error rate (‰) illustrate 1 7 383979 34 0.088546509 2 7.5 383979 11 0.0286474 3 8 383979 6 0.015625855 4 8.5 383979 7 0.018230164 5 9 383979 1 0.002604309 6 9.5 383979 1 0.002604309 7 10 383979 1 0.002604309 8 10.5 383979 0 0 9 11 383979 0 0 10 11.5 383979 0 0 11 12 383979 0 0 12 12.5 383979 0 0 13 13 383979 0 0 14 13.5 383979 0 0 15 14 383979 0 0 Table 3 Serial Number Signal-to-noise ratio (dB) Total number of symbols Error count Bit error rate (‰) illustrate 1 7 383979 167 0.434919618 2 7.5 383979 118 0.307308473 3 8 383979 75 0.195323182 4 8.5 383979 52 0.135424073 5 9 383979 32 0.083337891 6 9.5 383979 29 0.075524964 7 10 383979 11 0.0286474 8 10.5 383979 10 0.026043091 9 11 383979 8 0.020834473 10 11.5 383979 6 0.015625855 11 12 383979 3 0.007812927 12 12.5 383979 0 0 13 13 383979 0 0 14 13.5 383979 0 0 15 14 383979 0 0 It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0110] The above is an introduction to the method embodiments. The following describes the solution of the present invention further through an apparatus embodiment that has the same inventive concept as the method in the foregoing embodiments.

[0111] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the described module can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0112] The acquisition, storage, and application of user personal information involved in the technical solution of this invention all comply with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0113] It should be understood that the various processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein. The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A binary baseband signal bit synchronization method, characterized in that, include: Acquiring baseband data and application scenarios for baseband data; Perform binary sign determination on the baseband data to obtain baseband bit data; The ratio of the baseband bit data sampling rate to the baseband bandwidth is used as the oversampling rate; The midpoint of the count is calculated based on the oversampling rate. Based on the oversampling rate and the midpoint of the count, the baseband bit data is counted and synchronized using preset filter bits, synchronization counters, a first missynchronization avoidance counter, and a second missynchronization avoidance counter; while counting and synchronizing, the baseband bit data or baseband data is subject to majority decision based on the application scenario of the baseband data to obtain synchronization bit data; The synchronization bit data is used as the result of binary baseband signal bit synchronization.

2. The method according to claim 1, characterized in that, The step of using preset filter bits, synchronization counters, a first missynchronization avoidance counter, and a second missynchronization avoidance counter to count and synchronize the baseband bit data includes: Iterate through all bits in the baseband bit data; The synchronization conditions for each bit of data are set based on the filter bit, the synchronization counter, the first missynchronization avoidance counter, and the second missynchronization avoidance counter. The synchronization counter is adjusted based on the synchronization conditions of each bit of data.

3. The method according to claim 2, characterized in that, Synchronization conditions include: The first synchronization condition is that the bit data is not equal to the filtered bit. The second synchronization condition is that if the oversampling rate is not less than the third oversampling rate threshold, the bit data is the same as the N bits following it; if the oversampling rate is not less than the first oversampling rate threshold and less than the third oversampling rate threshold, the bit data is the same as the M bits following it. The third synchronization condition is that the first condition is to avoid missynchronization. The counter's count data must equal the oversampling rate. The fourth synchronization condition is that the count data of the synchronization counter equals the midpoint of the count; The fifth synchronization condition is that the oversampling rate is odd and the count data of the synchronization counter is equal to the midpoint of the count plus one. The sixth synchronization condition is that the count data of the second anti-missynchronization counter is equal to Z; where Z is a value set according to the oversampling rate.

4. The method according to claim 2, characterized in that, The step of adjusting the synchronization counter according to the synchronization condition of each bit of data includes: The synchronization counter performs its first count based on the synchronization condition. Perform a second count on the synchronous counter following the first count; The step of performing a first count on the synchronization counter according to the synchronization condition includes: When the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met: if the count data of the synchronization counter is less than the midpoint of the count, then when the count data of the synchronization counter is not greater than the first threshold, the count data of the synchronization counter is cleared to zero; when the count data of the synchronization counter is greater than the first threshold, the difference between the count data of the synchronization counter and the result of dividing the count data of the synchronization counter by 2 and taking the integer value is used as the count data of the synchronization counter. When the first, second, and third synchronization conditions are all met, if the fourth or fifth synchronization condition is met, the count data of the synchronization counter is incremented by one when the sixth synchronization condition is met; if the sixth synchronization condition is not met, the count data of the synchronization counter remains unchanged. If neither the fourth nor the fifth synchronization condition is met and the count data of the synchronization counter is greater than the midpoint of the count, the count data of the synchronization counter is cleared to zero when the count data of the synchronization counter is equal to the oversampling rate minus 1; if the count data of the synchronization counter is not equal to the oversampling rate minus 1, the count data of the synchronization counter is calculated based on the oversampling rate. The second counting of the synchronization counter includes: if the count data of the synchronization counter is less than the oversampling rate minus 1, then increment the count data of the synchronization counter by 1; otherwise, clear the count data of the synchronization counter to zero.

5. The method according to claim 4, characterized in that, Before the synchronization counter performs the second count, the second missynchronization avoidance counter, the first missynchronization avoidance counter, and the filter bit are adjusted in sequence to set the synchronization condition of the next bit of baseband bit data. Adjusting the second synchronization avoidance counter includes: when the first synchronization condition, the second synchronization condition, and the third synchronization condition are all met: if the fourth or fifth synchronization condition is met and the sixth synchronization condition is not met, then increment the count data of the second synchronization avoidance counter by 1; if neither the fourth nor the fifth synchronization condition is met, or the sixth synchronization condition is met, then clear the count data of the second synchronization avoidance counter to zero. Adjusting the first synchronization avoidance counter includes: if the third synchronization condition is not met, incrementing the count data of the first synchronization avoidance counter by 1; if the third synchronization condition and the first synchronization condition are met and the second synchronization condition is not met, setting the count data of the first synchronization avoidance counter to 1; otherwise, keeping the count data of the first synchronization avoidance counter unchanged. The filter bit is adjusted as follows: if the first synchronization condition is met and the second synchronization condition is not met, the filter bit is equal to the inverted bit data; if both the first and second synchronization conditions are met, the filter bit is equal to the bit data; otherwise, the filter bit remains unchanged.

6. The method according to claim 2, characterized in that, Before setting the synchronization conditions for each bit of data, the following is also included: If the count data of the synchronization counter is equal to the midpoint of the count, then the baseband bit data or baseband data is subject to majority voting based on the application scenario of the baseband data to obtain the synchronization bit data.

7. The method according to claim 6, characterized in that, The majority decision-making process for baseband bit data or baseband data based on the application scenario of the baseband data includes: The decision parameters are set based on the oversampling rate and the second oversampling threshold; The decision threshold is set according to the decision parameters and the application scenario of the baseband data: if the application scenario of the baseband data is an IoT system, the decision threshold is equal to the decision parameters; if the application scenario of the baseband data is a non-IoT system, the decision threshold is set to 0. The decision sum is calculated based on the baseband bit data, baseband data, and the application scenario of the baseband data: If the application scenario of the baseband data is an IoT system, the decision sum is calculated based on the baseband bit data when the synchronization counter equals the midpoint of the count; if the application scenario of the baseband data is a non-IoT system, the decision sum is calculated based on the baseband data when the synchronization counter equals the midpoint of the count. If the decision sum is not greater than the decision threshold, the output synchronization bit data is 0; otherwise, the output synchronization bit data is 1.

8. The method according to claim 7, characterized in that, The decision parameters for setting the oversampling rate and the second oversampling rate threshold include: if the oversampling rate is not less than the first oversampling rate threshold and is less than the second oversampling rate threshold, then the decision parameters are calculated based on the oversampling rate; if the oversampling rate is not less than the second oversampling rate threshold, then the decision parameters are calculated based on the second oversampling rate threshold. The calculation of the decision parameters based on the oversampling rate includes: The calculation of the decision parameters based on the second oversampling rate threshold includes: Where X is a preset value; Floor is the floor function.

9. The method according to claim 7, characterized in that, The calculation of the decision sum based on baseband bit data includes: The sum of the current bit data, the first K bits of the current bit data, and the last K bits of the current bit data in the baseband bit data is used as the decision sum; where K is the decision parameter.

10. The method according to claim 7, characterized in that, The step of calculating the decision sum based on baseband data includes: taking the current baseband data, the sum of the first K baseband data of the current baseband data, and the sum of the last K baseband data of the current baseband data as the decision sum; where K is the decision parameter.

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