A 2.4g wireless communication distance enhancement method based on bit repetition coding

Abstract

The application relates to a 2.4G wireless communication distance enhancement method based on bit repetition coding. The method comprises the following steps: bit repetition coding is performed on an original binary data bit stream at a sending end to repeatedly send each original bit N times to generate a sending bit sequence after repetition coding; a demodulation bit sequence is obtained after demodulation at a receiving end, the demodulation bit sequence is grouped according to every N continuous bits to obtain a plurality of bit groups, majority judgment is performed on each bit group to output a judgment result, and meanwhile, the judgment results are spliced in sequence to recover the original binary data bit stream; and the application solves the problems that the existing 2.4GHz wireless communication system has insufficient anti-interference capability, poor edge distance communication reliability, and the like under the premise of not increasing transmission power, not changing hardware and not reducing data rate.

Description

Technical Field

[0001] This invention belongs to the field of low-power wireless communication technology, and specifically relates to a method for enhancing the distance of 2.4G wireless communication based on bit repetition coding. Background Technology

[0002] Short-range wireless communication systems in the 2.4GHz ISM band, such as wireless mice, remote controls, and sensor networks, are common applications. However, the 2.4GHz band is currently dominated by numerous devices, and faces strong interference sources such as Wi-Fi, Bluetooth, and microwave ovens. Communication distance is limited by transmit power (typically a maximum of 10dBm), receiver sensitivity, path loss, and co-channel interference. Extending the effective communication distance in complex environments without increasing transmit power (limited by industry standards or power consumption) remains a long-standing technical challenge in this field.

[0003] Existing 2.4G communication systems typically balance distance and speed in the following ways: Method 1: Reduce the physical layer data rate: For example, reducing the data rate from 2Mbps to 250kbps narrows the receiver bandwidth and reduces thermal noise power, thereby achieving a sensitivity improvement of about 9~12dB and effectively extending the communication distance. Although Method 1 is effective in reducing the data rate, some applications require high real-time performance or throughput, such as wireless audio, and cannot arbitrarily reduce the rate.

[0004] Method 2, increase transmit power: Increase transmit power from 0dBm to 10dBm or even 20dBm through an external power amplifier to directly increase signal strength; however, this method is strictly limited by industry standards, and the 2.4GHz SRD band is generally ≤20dBm, and the power consumption increases sharply, making it unsuitable for battery-powered devices.

[0005] Method 3, Forward Error Correction (FEC): Redundant parity bits, such as Hamming codes or convolutional codes, are added to the data at the transmitting end, and the receiving end uses the redundancy to correct some erroneous bits. Method 3 requires a dedicated hardware FEC module or complex software algorithm, increasing chip cost and development difficulty, and the overhead of redundant bits is fixed, resulting in poor flexibility.

[0006] Therefore, existing technologies lack a low-cost range enhancement solution that can be implemented purely in software without changing the transmit power, reducing the peak data rate, requiring no dedicated FEC hardware. Summary of the Invention

[0007] The purpose of this invention is to provide a method for enhancing the distance of 2.4G wireless communication based on bit repetition coding. This invention aims to solve the problems of insufficient anti-interference capability and poor reliability of edge distance communication in existing 2.4GHz wireless communication systems without increasing transmission power, changing hardware, or reducing data rate.

[0008] To address the aforementioned technical problems, this invention provides a 2.4G wireless communication distance enhancement method based on bit repetition coding, comprising: By performing bit repetition encoding on the original binary data bit stream at the sending end, each original bit is sent N times to generate a repetition-encoded bit sequence, which serves as the payload of the data packet; where the number of repetitions N is an odd number and N≥1, and when N is 1, it indicates no repetition encoding, and each original bit is sent directly once; After demodulation at the receiving end, a demodulated bit sequence is obtained. The demodulated bit sequence is then grouped into several bit groups according to N consecutive bits. A majority decision is performed on each bit group, and the decision result is output. At the same time, the decision results of each group are concatenated in order to recover the original binary data bit stream. The majority decision includes: counting the number of "1" bits CNT in each bit group. If CNT ≥ (N+1) / 2, the bit is output as 1; otherwise, the bit is output as 0.

[0009] Preferably, the structure of the data packet includes: a preamble, a repeat-encoded synchronization word, a payload, and a checksum; the repeat-encoded synchronization word is inserted between the preamble and the payload, and the repeat-encoded synchronization word is used to indicate the number of repetitions N used in the current data packet.

[0010] Preferably, the transmitting end further includes: using the transmitted bit sequence as the payload of the data packet while maintaining the original modulation scheme and transmission power, and transmitting the data packet after inserting the repeated coded synchronization word at the original transmission rate.

[0011] Preferably, the receiving end further includes: obtaining a demodulated bit sequence after demodulation at the receiving end, and determining the repetition count N of the current data packet based on the repetition encoding synchronization word.

[0012] Preferably, the majority determination further includes: The decision result is obtained by querying the majority decision index table pre-stored at the receiving end; the majority decision index table has a length of 2. N The index value range is 0~2 N -1; Furthermore, the value of the entry corresponding to the index is: after converting the index into an N-bit binary number, if CNT≥(N+1) / 2, then the entry value is 1; otherwise, the entry value is 0.

[0013] Preferably, when N=1, the majority decision index table is {0,1}, and the majority decision is to output the single bit of the input directly as the decision result; When N=3, the majority decision index table is {0,0,0,1,0,1,1,1}, where each element corresponds to the decision result of the 3-bit input combination represented by indices 0-7, including: When the index is 0 to 2, the value of the entry is 0; when the index is 3 to 5, the value of the entry is 1 and the condition is that at least 2 bits in the 3-bit input combination are 1; when the index is 6 to 7, the value of the entry is 1.

[0014] Preferably, the receiver further includes an adaptive repetition count adjustment mechanism to dynamically adjust the redundancy based on channel quality, thereby achieving a balance between reliability and throughput; including: The receiving end periodically calculates the packet error rate (PER) of the current communication link; The comparison result is obtained by comparing the packet error rate PER with the preset packet error rate threshold; Based on the comparison result, an adjustment request for the repetition count N is generated and fed back to the sending end via a response packet; The sending end adjusts the repetition count N value used in subsequent data packet transmissions according to the received adjustment request.

[0015] Preferably, generating an adjustment request for the number of repetitions N based on the comparison result includes: When N=1, if the packet error rate PER is higher than the first threshold, a switch to N=3 is requested; otherwise, N=1 is maintained. When N=3, if the packet error rate PER is higher than the first threshold, a switch to N=5 is requested; if the packet error rate PER is lower than the second threshold, a switch to N=1 is requested; if the packet error rate PER is between the first threshold and the second threshold, N=3 is maintained. When N=5, if the packet error rate PER is higher than the first threshold, then N=5 is maintained; if the packet error rate PER is lower than the second threshold, then a switch to N=3 is requested; if the packet error rate PER is between the first threshold and the second threshold, then N=5 is maintained.

[0016] Preferably, the first threshold is greater than the second threshold; the first threshold is 10%, and the second threshold is 1%.

[0017] Preferably, the optimal value of the number of repetitions N is 3, so as to obtain the optimal trade-off between processing gain and throughput in a typical indoor 2.4GHz interference environment.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention provides a method for repeatedly transmitting each information bit an odd number of times, typically three times, at the software level, and performing majority decision at the receiving end, thereby trading time for processing gain and extending the effective communication distance in some scenarios, especially suitable for environments with sudden interference and fading channels.

[0019] 2. This invention improves edge communication distance: In a typical indoor environment, with N=3, under the same bit error rate, the effective communication distance is extended by 30%~50% compared to the non-repetition mode.

[0020] 3. This invention enhances the ability to resist sudden interference: it can correct most bits in a single or two random bit errors and has high robustness to instantaneous noise pulses.

[0021] 4. This invention has zero hardware cost: It only requires modification of the communication protocol stack software. It can be applied simply by adding encoding and decoding functions at both the transmitting and receiving ends and modifying the data packet length definition. No changes are required to any radio frequency hardware. It can be quickly ported to various low-power wireless platforms and is suitable for a large number of existing 2.4G chips. Attached Figure Description

[0022] Figure 1 The flowchart illustrates a 2.4G wireless communication distance enhancement method based on bit repetition coding provided by this invention.

[0023] Figure 2 The transmitter processing flowchart provided by this invention.

[0024] Figure 3 This is a data packet structure diagram provided by the present invention.

[0025] Figure 4 The receiving end processing flowchart provided by the present invention.

[0026] Figure 5 The flowchart of the adaptive repetition number adjustment mechanism provided by the present invention. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0028] like Figure 1 As shown, this embodiment of the invention specifically provides a 2.4G wireless communication distance enhancement method based on bit repetition coding, including: By performing bit repetition encoding on the original binary data bit stream at the sending end, each original bit is sent N times to generate a repetition-encoded bit sequence, which serves as the payload of the data packet; where the number of repetitions N is an odd number and N≥1, and when N is 1, it indicates no repetition encoding, and each original bit is sent directly once; After demodulation at the receiving end, a demodulated bit sequence is obtained. The demodulated bit sequence is then grouped into several bit groups according to N consecutive bits. A majority decision is performed on each bit group, and the decision result is output. At the same time, the decision results of each group are concatenated in order to recover the original binary data bit stream. The majority decision includes: counting the number of "1" bits CNT in each bit group. If CNT≥(N+1) / 2, the bit is output as 1; otherwise, the bit is output as 0.

[0029] This invention employs bit repetition encoding on the original binary data bitstream at the transmitting end: each original bit is repeated N times, where N is an odd number and N≥1, typically N=3. At the receiving end, N consecutively received bits at the same position are buffered, and the original bits are recovered using majority decision logic. Simultaneously, this invention introduces an adaptive repetition number adjustment mechanism, dynamically switching the value of N (e.g., N=1, 3, 5, etc.) based on the received signal quality and packet error rate (PER).

[0030] As a further step, the sending end processing flow, such as Figure 2 As shown: 1) Raw data bit stream (b_i): b0, b1, b2, ..., such as 1, 0, 1; 2) Repeat encoder: Each b_i is copied 3 times to obtain the transmission sequence: b0, b0, b0, b1, b1, b1, b2, b2, b2,…; 3) Maintain the original modulation method and transmission power, and transmit at the original rate; 4) For synchronization, a fixed "repetition code synchronization word" is inserted after the data packet preamble to inform the receiver of the current repetition count. The data packet composition is as follows: Figure 3 As shown, the structure of the data packet includes: a preamble, a repeat-encoded synchronization word, a payload, and a checksum; the repeat-encoded synchronization word is inserted between the preamble and the payload, and the repeat-encoded synchronization word is used to indicate the number of repetitions N used in the current data packet.

[0031] The receiving end processing flow, such as Figure 4 As shown: 1) The demodulated bit sequence is: r0, r1, r2, r3, r4, r5, r6, r7, r8, ... where r0~r2 correspond to the three transmissions of the original b0; 2) Grouping: Every 3 consecutive bits form a group {r_{3k}, r_{3k+1}, r_{3k+2}}; 3) Majority Decision: For each group, a vote is taken, and the bit value that appears most frequently is output. If the received 3 bits are {1, 0, 1}, the decision is 1; if they are {0, 0, 1}, the decision is 0. This is achieved by introducing a decision index table. The decision result is obtained by querying a pre-stored majority decision index table. This table contains 8 elements. Indices 0-2 return 0, indices 3-5 return 1 if at least 2 bits are 1, and indices 6-7 return 1. The specific implementation of the majority decision index table is {0, 0, 0, 1, 0, 1, 1, 1}. 4) Output the recovered original bitstream data.

[0032] The transmitting end also includes: using the transmitted bit sequence as the payload of the data packet while keeping the original modulation scheme and transmission power unchanged, and transmitting the data packet after inserting the repeated coded synchronization word at the original transmission rate.

[0033] The receiving end also includes: obtaining a demodulated bit sequence after demodulation at the receiving end, and determining the repetition count N of the current data packet based on the repetition encoding synchronization word.

[0034] The majority determination also includes: The decision result is obtained by querying the majority decision index table pre-stored at the receiving end; the majority decision index table has a length of 2. N The index value range is 0~2 N -1; Furthermore, the value of the entry corresponding to the index is: after converting the index into an N-bit binary number, if CNT≥(N+1) / 2, then the entry value is 1; otherwise, the entry value is 0.

[0035] When N=1, the majority decision index table is {0,1}, and the majority decision is to directly output the single bit of the input as the decision result. When N=3, the majority decision index table is {0,0,0,1,0,1,1,1}, where each element corresponds to the decision result of the 3-bit input combination represented by indices 0-7, including: When the index is 0 to 2, the value of the entry is 0; when the index is 3 to 5, the value of the entry is 1 and the condition is that at least 2 bits in the 3-bit input combination are 1; when the index is 6 to 7, the value of the entry is 1.

[0036] The receiver also includes an adaptive repetition count adjustment mechanism to dynamically adjust redundancy based on channel quality, thereby achieving a balance between reliability and throughput; including: The receiving end periodically calculates the packet error rate (PER) of the current communication link; The comparison result is obtained by comparing the packet error rate PER with the preset packet error rate threshold; Based on the comparison result, an adjustment request for the repetition count N is generated and fed back to the sending end via a response packet; The sending end adjusts the repetition count N value used in subsequent data packet transmissions according to the received adjustment request.

[0037] like Figure 5 As shown, the adjustment request for generating the repetition count N value based on the comparison result includes: When N=1, if the packet error rate PER is higher than the first threshold, a switch to N=3 is requested; otherwise, N=1 is maintained. When N=3, if the packet error rate PER is higher than the first threshold, a switch to N=5 is requested; if the packet error rate PER is lower than the second threshold, a switch to N=1 is requested, i.e., no duplicates, to improve throughput; if the packet error rate PER is between the first threshold and the second threshold, N=3 is maintained. When N=5, if the packet error rate PER is higher than the first threshold, then N=5 is maintained; if the packet error rate PER is lower than the second threshold, then a switch to N=3 is requested; if the packet error rate PER is between the first threshold and the second threshold, then N=5 is maintained; wherein, the first threshold is greater than the second threshold; the first threshold is 10%, and the second threshold is 1%.

[0038] In summary, this invention combines odd-bit repetition encoding with majority decision-making, achieving the lowest complexity, especially when N=3, while still correcting single-bit errors. It utilizes a fast majority decision-making based on an index table: creating a constant array of only 8 elements {0,0,0,1,0,1,1,1} pre-calculates the majority result for all possible combinations of 3-bit groups. During decoding, only a single byte-level index read is needed to complete a 1-bit decision, avoiding conditional jumps and bit-by-bit counting, significantly improving execution efficiency on the MCU. Furthermore, it employs pure software implementation, without relying on dedicated hardware: it can be directly modified within the protocol stack of existing MCUs or 2.4G transceiver chips, resulting in extremely low cost. Finally, it employs an adaptive repetition count adjustment mechanism: dynamically switching the N value based on channel quality, maintaining high speed at close range and automatically switching to a high-reliability mode at long distances or with strong interference.

[0039] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A method for enhancing the distance of 2.4G wireless communication based on bit repetition coding, characterized in that, include: By performing bit repetition encoding on the original binary data bit stream at the sending end, each original bit is sent N times to generate a repetition-encoded bit sequence, which serves as the payload of the data packet; where the number of repetitions N is an odd number and N≥1, and when N is 1, it indicates no repetition encoding, and each original bit is sent directly once; After demodulation at the receiving end, a demodulated bit sequence is obtained. The demodulated bit sequence is grouped into several bit groups according to N consecutive bits. A majority decision is made on each bit group and the decision result is output. At the same time, the decision results of each group are concatenated in order to recover the original binary data bit stream. The majority decision includes: counting the number of "1" bits CNT in each bit group; if CNT ≥ (N+1) / 2, then output bit 1; otherwise, output bit 0.

2. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 1, characterized in that, The data packet structure includes: a preamble, a repeat-encoded synchronization word, a payload, and a checksum; the repeat-encoded synchronization word is inserted between the preamble and the payload, and the repeat-encoded synchronization word is used to indicate the number of repetitions N used in the current data packet.

3. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 2, characterized in that, The transmitting end also includes: using the transmitted bit sequence as the payload of the data packet while keeping the original modulation scheme and transmission power unchanged, and transmitting the data packet after inserting the repeated coded synchronization word at the original transmission rate.

4. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 3, characterized in that, The receiving end also includes: obtaining a demodulated bit sequence after demodulation at the receiving end, and determining the repetition count N of the current data packet based on the repetition encoding synchronization word.

5. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 1, characterized in that, The majority determination also includes: The decision result is obtained by querying the majority decision index table pre-stored at the receiving end; the majority decision index table has a length of 2. N The index value range is 0~2 N -1; Furthermore, the value of the entry corresponding to the index is: after converting the index into an N-bit binary number, if CNT≥(N+1) / 2, then the entry value is 1; otherwise, the entry value is 0.

6. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 5, characterized in that, When N=1, the majority decision index table is {0,1}, and the majority decision is to directly output the single bit of the input as the decision result. When N=3, the majority decision index table is {0,0,0,1,0,1,1,1}, where each element corresponds to the decision result of the 3-bit input combination represented by indices 0-7, including: When the index is 0 to 2, the value of the entry is 0; when the index is 3 to 5, the value of the entry is 1 and the condition is that at least 2 bits in the 3-bit input combination are 1; when the index is 6 to 7, the value of the entry is 1.

7. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 1, characterized in that, The receiver also includes an adaptive repetition count adjustment mechanism to dynamically adjust redundancy based on channel quality, thereby achieving a balance between reliability and throughput; including: The receiving end periodically calculates the packet error rate (PER) of the current communication link; The comparison result is obtained by comparing the packet error rate PER with the preset packet error rate threshold; Based on the comparison result, an adjustment request for the repetition count N is generated and fed back to the sending end via a response packet; The sending end adjusts the repetition count N value used in subsequent data packet transmissions according to the received adjustment request.

8. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 7, characterized in that, The request to generate an adjustment request for the number of repetitions N based on the comparison results includes: When N=1, if the packet error rate PER is higher than the first threshold, a switch to N=3 is requested; otherwise, N=1 is maintained. When N=3, if the packet error rate PER is higher than the first threshold, a switch to N=5 is requested; if the packet error rate PER is lower than the second threshold, a switch to N=1 is requested; if the packet error rate PER is between the first threshold and the second threshold, N=3 is maintained. When N=5, if the packet error rate PER is higher than the first threshold, then N=5 is maintained; if the packet error rate PER is lower than the second threshold, then a switch to N=3 is requested; if the packet error rate PER is between the first threshold and the second threshold, then N=5 is maintained.

9. The 2.4G wireless communication distance enhancement method based on bit repetition coding as described in claim 8, characterized in that, The first threshold is greater than the second threshold; the first threshold is 10%, and the second threshold is 1%.

10. A 2.4G wireless communication distance enhancement method based on bit repetition coding as described in any one of claims 1 to 9, characterized in that, The optimal value for the number of repetitions N is 3, so as to obtain the best trade-off between processing gain and throughput in a typical indoor 2.4GHz interference environment.

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