A short code encoding structure and a chimeric confidentiality transmission method using the same

Abstract

This invention discloses a short code encoding structure and an embedded secure transmission method using this structure, applicable to wireless encoding / decoding technology and automatic control fields. The method includes: using a preset number of equal-width high and low level pulses as a starting segment, connecting a 2ms-8ms wide high-level pulse, followed by sequentially connecting an identification code, an address code, a data code, and a check code; for the discrimination of "0" and "1" signals, specifically: 1 high n low is defined as signal "0", n high 1 low is defined as signal "1", and all other cases are considered invalid data; wherein, the value of n is as follows: when the code length requirement is higher than a preset threshold, n = 2; when the code length requirement is lower than the preset threshold, n > 2. This invention achieves better secure transmission, reduces power consumption, reduces the bit error rate, meets the low power requirements of small devices, and reduces CPU overhead and system power consumption costs.

Description

Technical Field

[0001] This invention relates to the fields of wireless encoding and decoding technology and automatic control, and particularly to a short code encoding structure and an embedded secure transmission method using the structure. Background Technology

[0002] Wireless control devices are now widely used both domestically and internationally, employing a wide variety of frequency bands, with common civilian bands including 315MHz, 433MHz, and 2.4GHz. Remote control encoding and decoding schemes are mature, offering the advantages of easy chip integration and information copying, thus significantly reducing costs. However, a drawback is that reading the original remote control data allows for the duplication of the "key," the potential risks of which are obvious. Unauthorized individuals can use technical means to remotely obtain remote control signals and commit theft. To ensure the security and confidentiality of wireless remote control, anti-copying technologies such as rolling codes are increasingly used, but they can still be cracked. Some encoding and decoding schemes using encryption algorithms have achieved significant results, but they significantly increase the number of bits required for encoding, reducing transmission efficiency and increasing power consumption. Therefore, how to better achieve secure transmission, reduce power consumption, and decrease the error rate remains a pressing issue.

[0003] Radio frequency identification (RFID) systems typically use one of the following encoding methods: Non-Return-to-Zero (NRZ) encoding, Manchester encoding, Unipolar Return-to-Zero (UZZ) encoding, Differential Biphasic (DBP) encoding, Miller encoding, and Differential encoding. In simple terms, it uses different pulse signals to represent 0 and 1. Among these, NRZ encoding is prone to generating long high and long low levels, such as... Figure 1 As shown, this method is inefficient, prone to bit errors and zero-level interference, and cannot extract synchronization signals, so it is rarely used anymore. In Manchester encoding, however, the value of a bit is represented by the level change (rising / falling) within half a bit cycle of that bit length. A negative transition within half a bit cycle represents binary "1", and a positive transition represents binary "0". This level change within half a bit cycle avoids long high or long low levels. Figure 2As shown, Manchester encoding, when employing load modulation or backscatter modulation, is typically used for data transmission from electronic tags to readers because it facilitates the detection of data transmission errors. This is because a "no change" state is not allowed within the bit length. When multiple electronic tags simultaneously transmit data bits with different values, the received rising and falling edges cancel each other out, resulting in a continuous subcarrier signal throughout the entire bit length. Since this state is not allowed, the reader can use this error to determine the specific location of the collision. However, if the decoding end uses a level-based discrimination mode, bit errors may occur. Other encoding methods also determine the "0" and "1" signals based on the length of high and low levels or changes in the edges within a period, each with its own advantages and disadvantages.

[0004] Furthermore, the wireless channel environment is harsh and unpredictable. Radio wave transmission not only suffers from propagation path loss but is also affected by adverse factors such as multipath effects, Doppler shift, and shadowing effects, which greatly impact communication quality. Channel coding techniques have undergone decades of development, from early Hamming codes, BCH codes, and RS codes to later convolutional codes, concatenated codes, and today's Turbo codes and LDPC codes. The performance achievable is constantly narrowing the gap with the Shannon limit. These advanced channel coding techniques are now widely used in the field of communications.

[0005] Reed-Solomon (RS) code is an error-correcting code capable of correcting multiple errors. The RS code is (204, 188, t = 8), where t is the number of bytes of the robust length, corresponding to 188 symbols, and the check segment is 16 bytes (overhead byte segment). In practice, an RS encoding of (255, 239, t = 8) is implemented, which involves adding 51 bytes of all "0"s before the 204 bytes (including the synchronization byte), discarding the first 51 empty bytes after generating the RS code, resulting in a truncated (204, 188) RS code. The encoding efficiency of RS is 188 / 204. Typical applications include CDs and VCDs.

[0006] Turbo codes, also known as parallel concatenated convolutional codes, cleverly combine convolutional codes and random interleavers to achieve random coding. Turbo codes employ a simple concatenated convolutional code structure and a maximum a posteriori probability iterative decoding algorithm, achieving error correction and decoding performance close to the Shannon limit. A key feature of Turbo codes is that their component codes use recursive systematic convolutional codes, which is a major reason for their superior performance. Turbo code technology has been widely applied, and many of its key technologies have been improved to further enhance performance and facilitate hardware and software implementation. Turbo codes have been adopted as a standard for deep space communication in the United States and have also been selected as one of the channel coding schemes for third-generation mobile communication systems (IMT-2000). For example, 3GPP's WCDMA and CDMA2000, and China's TD-SCDMA all use Turbo channel coding schemes.

[0007] However, while these coding technologies possess advanced error correction and anti-interference capabilities, and their advanced modulation and coding techniques enable high-capacity, high-speed communication, their complex algorithms require CPUs with high-speed computing power and large-data-processing capabilities at both the transmitting and receiving ends to reduce latency. High power consumption and high cost are unavoidable. In fact, for miniaturized devices, the amount of data requiring encoding and decoding is very small. Therefore, for miniaturized devices, improving encoding and decoding efficiency, reducing CPU overhead, and lowering system power consumption are paramount.

[0008] Therefore, how to provide a short code encoding structure that addresses the problems of information leakage and easy reverse decoding in current wireless transmission, achieves better secure transmission, reduces power consumption and bit error rate, meets the low power requirements of small devices, and reduces CPU overhead and system power consumption costs, as well as the embedded secure transmission method using this structure, is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0009] In view of this, the present invention proposes a short code encoding structure and an embedded secure transmission method using the structure.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] A short code encoding structure, comprising:

[0012] A preset number of equal-width high and low level pulses are used as the starting segment, followed by 2ms-8ms wide and high level pulses. After the wide and high level pulses, the identification code, address code, data code, and check code are connected in sequence.

[0013] The specific steps for distinguishing between "0" and "1" signals are as follows:

[0014] The identification code, address code, data code, and check code define 1 high n low as signal "0", n high 1 low as signal "1", and all other cases are considered invalid data;

[0015] Among them, the high-level duty cycle of 1 high and n low is 1 / n+1; the high-level duty cycle of n high and 1 low is n / n+1.

[0016] The possible values ​​of n are as follows:

[0017] When the code length requirement is higher than the preset threshold, n = 2; when the code length requirement is lower than the preset threshold, n > 2, and n is an integer.

[0018] Optionally, for the discrimination of "0" and "1" signals, a variable duty cycle technique is also included, as follows:

[0019] The identification code uses n=a, specifically: the identification code defines 1 high and a low as signal "0", and a high and 1 low as signal "1";

[0020] The address code, data code, and check code use n=b. ​​Specifically, the address code, data code, and check code define 1 high and b low as signal "0", and b high and 1 low as signal "1".

[0021] All other cases are considered invalid data.

[0022] The present invention also provides an embedded secure transmission method utilizing a short code coding structure, comprising:

[0023] Based on the short code coding structure, the data is divided into two or more sub-codes guided by two or more different identification codes. These sub-codes are then transmitted in series through one or more transmitters. The receiving end combines the sub-codes according to the agreed identification code order and decodes them to obtain the complete transmitted data.

[0024] Optionally, when one or more transmitters transmit subcodes in series, each subcode segment is spaced by a preset duration.

[0025] As can be seen from the above technical solutions, compared with the prior art, this invention proposes a short code encoding structure and an embedded secure transmission method using this structure. This invention achieves better secure transmission, reduces power consumption and bit error rate, meets the low power requirements of small devices, and reduces CPU overhead and system power consumption costs by employing a short code encoding method consisting of a descrambling code, an identification code, an address code, a data code, and a check code. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the NRZ encoding method in the prior art.

[0028] Figure 2 This is a schematic diagram of the Manchester encoding method in the existing technology.

[0029] Figure 3 This is a waveform diagram of the short code encoding structure with n=2 according to the present invention.

[0030] Figure 4 This is a schematic diagram of the encoded waveform of the PT2262 chip in the prior art.

[0031] Figure 5 This is a waveform diagram of the variable duty cycle short code encoding structure of the present invention. Detailed Implementation

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] Example 1:

[0034] Embodiment 1 of the present invention discloses a short code encoding structure, such as Figure 3 As shown, including:

[0035] A preset number of equal-width high and low level pulses are used as the starting segment, i.e., the descrambling code. Then, 2ms-8ms of wide and high level pulses are connected. After the wide and high level pulses, the identification code, address code, data code, and check code are connected in sequence.

[0036] The commonly used 2262 and 2272 hardware codec chips have effectively solved the problems of zero-level interference and initial segment garbled characters, because "0", "1", and "f" are all high-level followed by low-level signals, distinguished by different duty cycles. Figure 4As shown, this avoids long high and long low levels. Four sets of data are transmitted repeatedly each time to prevent interference, because the first set of codes is easily interfered with. The receiver only considers two identical sets of address and data codes valid simultaneously. It can be seen that the high and low levels are in a 3:1 ratio. Figure 4 (4a and 12a) Of course, each codeword also needs a 4a high level followed by a 128a low level as a synchronization header. This invention adopts an efficient encoding method, which can greatly reduce the power consumption and time of a single transmission. The initial use of several equal-width high and low level pulses is to eliminate garbled characters in the receiving module. Although the 2ms-8ms wide high-level pulses reduce efficiency, they easily identify valid data and eliminate interference signals. The microprocessor only considers the data valid if it recognizes the valid width, which greatly improves the anti-interference capability of wireless products and reduces the bit error rate.

[0037] The specific steps for distinguishing between "0" and "1" signals are as follows:

[0038] The identification code, address code, data code, and check code define 1 high n low as signal "0", n high 1 low as signal "1", and all other cases are considered invalid data.

[0039] The high-level duty cycle for 1 high and n low is 1 / n+1; the high-level duty cycle for n high and 1 low is n / n+1.

[0040] The possible values ​​of n are as follows:

[0041] Here, n is a positive integer; as n increases, it has better fault tolerance for severe situations such as frequency drift and temperature drift, but the short code duration will increase.

[0042] Therefore, when the code length requirement is higher than the preset threshold, n = 2 (e.g. Figure 3 As shown, this discrimination scheme, for a set of 25 data bits, does not require a synchronization check code and uses a simple equal-interval level judgment scheme. Under conditions of no strong interference, its bit error rate does not exceed 1 / 2. 25 When the code length requirement is lower than the preset threshold (when the code length requirement is not high), n > 2, and n is an integer, the discrimination scheme further improves the reliability.

[0043] The discrimination of "0" and "1" signals also includes a variable duty cycle technique, which can further improve confidentiality, such as... Figure 5 As shown below:

[0044] The identification code uses n=a, specifically: the identification code defines 1 high and a low as signal "0", and a high and 1 low as signal "1";

[0045] The address code, data code, and check code use n=b. ​​Specifically, the address code, data code, and check code define 1 high and b low as signal "0", and b high and 1 low as signal "1".

[0046] All other cases are considered invalid data.

[0047] During decoding, different code segments are decoded according to the agreed variable duty cycle.

[0048] Practice has proven that the encoding method of this invention only requires sending one set of codes each time, eliminating the need for repeated transmissions, to achieve good decoding. Due to the short code structure, the check code uses the inverse of the data code instead of parity checking, ensuring data reliability without retransmission. Even when using a receiver module with spurious output (such as a super-regenerative module), sensitivity and reliability are not reduced. The 2ms-8ms wide high-level pulse of the new encoding ensures the reliability and convenience of subsequent decoding. A pulse wider than 10ms is not used because some transmitting modules experience a significant decrease in transmission efficiency and shorter transmission distance under a wider high-level mode, making the new encoding method more versatile.

[0049] The encoding structure of this invention adopts a descrambling code-identification code-address code-data code-check code approach, thereby enabling effective decoding with just one codeword transmitted. This significantly improves transmission efficiency and achieves satisfactory results regardless of whether the receiver uses super-regenerative or superheterodyne technology. For battery-powered receivers, low-power applications are often required. The short code mode of this invention achieves low power consumption at the receiver by employing the following method: The receiver periodically turns on the receiving module, using a wide and high level to determine whether to enter the receiving state. If there is no 2-8ms wide and high level, it re-enters the sleep standby state. If a 2-8ms high level is received, it remains awake and continues to receive signals. For example, if a signal transmission lasts 50ms, the receiver uses a 100ms on, 1s off approach. The transmitter needs to continuously transmit 22 signals (i.e., 1.1s) each time, ensuring that at least one complete signal falls into the receiver in the on state, thus achieving decoding. Since the receiver is in a 9 / 10 time period with the module off, if the current of the receiver module is 5mA when it is working, the average current drops to 0.5mA when using this mode, reducing power consumption by 10 times. By adjusting the power-on duty cycle, even lower power consumption can be achieved.

[0050] Example 2:

[0051] Embodiment 2 of the present invention discloses an embedded secure transmission method utilizing a short code coding structure, comprising:

[0052] Based on the short code encoding structure, the data is divided into two or more sub-codes guided by two or more different identification codes (with the same address code). These sub-codes are then transmitted in series through one or more transmitters. The receiving end combines the sub-codes according to the agreed identification code order and decodes them to obtain the complete transmitted data.

[0053] Unlike the default "0101" address start code, this invention uses an identification code compiled according to agreed-upon rules. This code serves as a special address for the receiving end. Different sets of sub-codes with the same address are sorted according to these rules to form a complete data code. This use of two or more sets of identification codes, much like multiple keys can open a single lock, provides a high level of security. Even if an attacker obtains all the data information of all sub-codes through various means, without the combination rules, they still cannot decode the data. This effectively improves data security. Theoretically, the greater the number of combinations, the higher the security level, but this also increases CPU overhead and reduces data transmission efficiency.

[0054] Meanwhile, when one or more transmitters send short codes in series, each short code is spaced by a preset duration (such as several seconds), causing some readers to believe that the code transmission has ended, thereby preventing theft.

[0055] Example 3:

[0056] Embodiment 3 of the present invention discloses a specific application of a short code encoding structure in Embodiment 1, as follows:

[0057] In automatic tracking headlamps, there is a wireless single-foot pedal technology. Its key feature is using a single switch to achieve multiple functions, including moving the head up and down, turning the light on and off, and adjusting brightness. The single-foot pedal technology works by pressing the pedal repeatedly to turn the light on, adjust brightness, and turn it off, with each press resulting in a different change in brightness, cycling sequentially. This single-foot pedal technology is primarily achieved by the CPU determining the pedal's delay time and transmitting data with different data codes at the same address. The decoding end then uses these different data codes to implement different functions. Its low power consumption is thanks to the short code encoding technology of this invention, allowing the wireless pedal to operate for a relatively long time even with a button lithium battery. The antenna uses a PCB antenna, which significantly reduces weight and size.

[0058] Significant advancements have been made in encoding and decoding technologies, enabling not only the identification and correction of bit errors. This is crucial for transmitting critical information. To achieve long-distance transmission, receiver sensitivity has increased dramatically, with some exceeding -120dBm. However, this high sensitivity also introduces substantial interference. The modulation method of the digital signal also affects the output signal quality. Commonly used techniques include Amplitude Shift Keying (ASK), Frequency Shift Keying (FSK), and Phase Shift Keying (PSK). In terms of both bandwidth utilization and noise immunity (or power efficiency), PSK is the most superior. For large-scale and high-speed transmissions, due to limited bandwidth resources, more complex modulation and coding techniques such as single-carrier frequency domain equalization and Orthogonal Frequency Division Multiplexing (OFDM) are employed. Both utilize block transmission and cyclic prefix structures, and employ FFT / I-FFT (Fast Fourier Transform / Inverse Fast Fourier Transform) for signal processing. This maximizes the utilization of limited spectrum resources, enabling high-speed wireless transmission and improving system transmission capacity and performance. However, not all wireless devices need to adopt the most advanced encoding technology. As the performance of encoding and decoding improves, higher requirements are placed on their hardware and software. This involves not only cost but also power consumption and size, which goes against the pursuit of lighter and smaller medical headlamps. The automatic tracking headlamp adopts a simple ASK modulation method, which only uses inverse code error checking and does not require error correction. It adopts the short code structure of descrambling code-identification code-address code-data code-check code in this invention. Each headlamp uses a different address code. With this extremely simple new encoding method, although a low-end CPU and 4M main frequency are used in actual use, it still shows excellent control performance. At the same time, the structure is lightweight and the power consumption is extremely low, which has achieved good clinical use results.

[0059] This invention discloses a short code encoding structure and a method for secure transmission using this structure. By employing a short code encoding scheme consisting of a descrambling code, an identification code, an address code, a data code, and a check code, and based on this, the invention performs secure data transmission using a method that achieves better secure transmission, reduces power consumption, lowers the bit error rate, meets the low power requirements of small devices, and reduces CPU overhead and system power consumption costs.

[0060] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0061] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A secure transmission method for wireless remote control signals based on a short code coding structure, characterized in that, The short code encoding structure is as follows: A preset number of equal-width high and low level pulses are used as the starting segment, followed by 2ms-8ms wide and high level pulses. The wide and high level pulses are then connected in sequence with the identification code, address code, data code, and check code. The specific steps for distinguishing between "0" and "1" signals are as follows: The identification code, address code, data code, and check code define 1 high n low as signal "0", n high 1 low as signal "1", and all other cases are considered invalid data; Wherein, the high-level duty cycle of the 1 high n low is 1 / n+1; the high-level duty cycle of the n high 1 low is n / n+1; The possible values ​​of n are as follows: When the code length requirement is higher than the preset threshold, n=2; when the code length requirement is lower than the preset threshold, n>2, and n is an integer. Based on the aforementioned short code encoding structure, data is divided into two or more sub-codes guided by two or more different identification codes. These sub-codes are then transmitted in series through one or more transmitters. The receiving end combines the sub-codes according to the agreed identification code order and decodes them to obtain the complete transmitted data.

2. The wireless remote control signal embedding and secure transmission method based on short code coding structure according to claim 1, characterized in that, The discrimination of "0" and "1" signals also includes a variable duty cycle technique, as follows: The identification code uses n=a, specifically: the identification code defines 1 high and a low as signal "0", and a high and 1 low as signal "1"; The address code, data code, and check code adopt n=b, specifically: the address code, data code, and check code define 1 high and b low as signal "0", and b high and 1 low as signal "1"; All other cases are considered invalid data.

3. The wireless remote control signal embedding and secure transmission method based on short code coding structure according to claim 1, characterized in that, When the one or more transmitters transmit subcodes in series, each subcode segment is spaced by a preset time interval.

Images