Method and device for improving USB data transmission rate

Abstract

The present invention discloses a method and device for improving the USB data transmission rate. In order to avoid bandwidth loss in USB data transmission, the present invention receives a data packet from a link layer in a logic sublayer of a transmitting end, removes the packet tail and part of the synchronization segment in the data packet from the link layer, and obtains a deleted data packet; arranges the deleted data packet into data segments in a data packet of a USB flow control unit according to a preset rule; calculates a CRC segment and a FEC segment according to the data segments in the data packet of the USB flow control unit, and splices the data segment, CRC segment and FEC segment in the data packet of the USB flow control unit together to form a data packet of the USB flow control unit; and sends the data packet of the USB flow control unit to a receiving end. The present invention can effectively avoid bandwidth loss and improve the USB data transmission rate.

Description

Technical Field

[0001] The invention relates to the field of communications, and in particular to a method and a device for improving USB data transmission rate. Background Art

[0002] Universal Serial Bus (USB) is an interface standard jointly launched by world-renowned computer and communication companies. It is fast and flexible.

[0003] During USB data transmission, the physical layer performs scrambling, descrambling, encoding, decoding and other functions. The encoding process mainly uses 8-bit to 10-bit and 128-bit to 130-bit encoding methods, the former will have a 20% bandwidth loss, and the latter will have a 1.54% bandwidth loss.

[0004] Encoding is the process of converting raw data into a format suitable for transmission on a physical medium. In USB, the main encoding method used is Non-Return to Zero Inverted (NRZI) encoding plus sign encoding. The basic rule of NRZI encoding is that each bit in the data stream is represented by a change in the voltage level on the transmission line.

[0005] Symbol encoding usually uses 8-bit to 10-bit encoding, which converts 8-bit data into 10-bit symbols to improve signal quality and ensure sufficient signal conversion (the so-called clock recovery capability), which ensures that the receiving end can correctly synchronize the signal. Decoding is the inverse operation of the encoding process, that is, converting the received signal back to the original data.

[0006] Scrambling is an additional step after encoding to further improve the quality of the signal and reduce electromagnetic interference. In USB, in order to reduce the DC bias and spectrum concentration caused by long sequences of "0" or "1", a scrambling algorithm is used to randomize the transmitted bit stream. This ensures that the spectrum of the signal is more evenly distributed and reduces interference to adjacent devices. Descrambling is the inverse operation of scrambling.

[0007] According to the above description, in the current USB transmission process, the symbol encoding link will cause the loss of data transmission bandwidth. Summary of the invention

[0008] In order to alleviate or partially alleviate the above technical problems, the solution of the present invention is as follows:

[0009] A method for improving USB data transmission rate comprises the following steps: receiving a data packet from a link layer in a logic sublayer of a transmitting end, removing a packet tail and a part of a synchronization segment in the data packet from the link layer, and obtaining a deleted data packet; arranging the deleted data packet into data segments in a data packet of a USB flow control unit according to a preset rule; calculating a CRC segment and an FEC segment according to the data segments in the data packet of the USB flow control unit, and splicing the data segments, CRC segments and FEC segments in the data packet of the USB flow control unit together to form a data packet of the USB flow control unit; and sending the data packet of the USB flow control unit to a receiving end.

[0010] Furthermore, in the logic sublayer of the sending end, a data packet from the protocol layer is also received, and a pruned data packet is obtained according to the data packet from the protocol layer.

[0011] Furthermore, before sending the data packet of the USB flow control unit to the receiving end, a scrambling operation is performed on the data packet of the USB flow control unit to obtain a scrambled data packet.

[0012] Furthermore, at the receiving end, the scrambled data packet is first descrambled, and then the descrambled data packet is sent to the logical sublayer of the receiving end.

[0013] Furthermore, in the logic sublayer of the receiving end, the FEC segment in the descrambled data packet is first parsed to determine whether there is a data error during the transmission process. If there is, error correction is directly performed to obtain error-corrected data.

[0014] Furthermore, whether the corrected data is correct is determined by using the CRC segment in the descrambled data packet; if the corrected data is correct, the corrected data is sent to the link layer and / or protocol layer of the receiving end.

[0015] A device for improving USB data transmission rate, the device for improving USB data transmission rate comprises a physical layer, the physical layer comprises a logic sublayer, the logic sublayer comprises a flow control unit; the flow control unit comprises an original packet processing module, a flow integration module and a flow control packet processing module; the original packet processing module receives a data packet from a link layer, and removes a packet tail and part of a synchronization segment from the data packet from the link layer to obtain a deleted data packet; the flow integration module arranges the deleted data packet into data segments in a data packet of a USB flow control unit according to a preset rule; the flow control packet processing module calculates a CRC segment and an FEC segment according to the data segments in the data packet of the USB flow control unit, and splices the data segment, CRC segment and FEC segment in the data packet of the USB flow control unit together to form a data packet of the USB flow control unit.

[0016] Furthermore, the original packet processing module also receives a data packet from the protocol layer, and obtains a deleted data packet according to the data packet from the protocol layer.

[0017] Furthermore, the device for increasing the USB data transmission rate is located in the transmitting end of the USB system.

[0018] The technical solution of the present invention has the following beneficial technical effects:

[0019] Reduce the bandwidth loss in USB data transmission and increase the USB data transmission rate.

[0020] In addition, other beneficial effects of the present invention will be mentioned in the specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the physical layer function of the traditional USB transmitter;

[0022] Figure 2 It is a schematic diagram of the position relationship of the flow control unit of the present invention;

[0023] Figure 3 It is a schematic diagram of the data packet structure of the USB flow control unit of the present invention;

[0024] Figure 4 It is a schematic diagram of the structure of the flow control unit of the present invention;

[0025] Figure 5 It is a data processing flow chart of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0027] In order to clearly describe the technical solutions of the embodiments of the present invention, in the embodiments of the present invention, words such as "first" and "second" are used to distinguish the same or similar items with substantially the same functions and effects. Those skilled in the art can understand that words such as "first" and "second" do not limit the quantity and execution order.

[0028] In the USB system, the electrical sublayer focuses on the physical transmission characteristics of the signal, including voltage level, current limit, signal waveform, etc. In the USB system, the electrical sublayer defines how the signal is transmitted on the physical medium (usually wires). The electrical sublayer of the USB system specifies the following electrical characteristics: signal type, voltage range, and impedance matching.

[0029] The physical layer is responsible for converting the signals defined by the electrical sublayer into actual physical transmission. The physical layer focuses on the physical characteristics of the signals and how to actually transmit these signals on the physical medium. In the USB system, the physical layer specifies functions such as signal encoding, signal rate, signal modulation and scrambling. In the present invention, the physical layer includes a logical sublayer and an electrical sublayer.

[0030] Figure 1 This is a functional diagram of the physical layer of a traditional USB transmitter. After the input signal is processed by the scrambling module, it is then coded by the symbol coding module, and then processed by the parallel-to-serial conversion module before being sent to the differential driver to generate an output signal. The existence of the symbol coding module causes bandwidth loss.

[0031] Figure 2 The technical concept of the present invention is to cancel the physical layer 8-bit to 10-bit and 128-bit to 130-bit encoding of the USB system, and use the flow control encoding belonging to 1-bit to 1-bit encoding in the logical sublayer of the sending end to improve the data transmission rate or efficiency.

[0032] The logical sublayer in the physical layer of the transmitting end of the present invention includes a flow control unit. The flow control unit receives data packets from the link layer.

[0033] After the traffic control unit encodes the data packet from the link layer, it goes through other processing steps of the physical layer of the sender, such as performing scrambling operations through the scrambling module, and is finally sent to the receiver.

[0034] Figure 3 The data packet structure diagram of the USB flow control unit of the present invention includes a data segment, a cyclic redundancy check (CRC) segment and a forward error correction (FEC) segment.

[0035] The device for improving USB data transmission rate in the present invention comprises a physical layer, the physical layer comprises a logical sublayer, and the logical sublayer comprises a flow control unit.

[0036] Furthermore, the device for increasing USB data transmission rate of the present invention is located in the transmitting end of the USB system.

[0037] Figure 4 The flow control unit of the present invention comprises an original packet processing module, a flow integration module and a flow control packet processing module.

[0038] In the present invention, a flow control unit is set in the logical sublayer in the physical layer of the transmitting end, and the 8-bit to 10-bit and 128-bit to 130-bit encoding operations are no longer performed in the physical layer of the transmitting end.

[0039] The traffic control unit receives data packets from the link layer, and removes the End Of Packet (EOP) and part of the synchronization (SYNChronize, SYNC) segments from the data packets from the link layer through the original packet processing module to obtain the deleted data packets, which are then sent to the traffic integration module.

[0040] Alternatively, the flow control unit may also receive data packets from the protocol layer.

[0041] In the traffic integration module, the deleted data packets are arranged as data segments in the data packets of the USB traffic control unit, so as to rearrange the data packets from the link layer and transmit them in data segments of fixed length.

[0042] Furthermore, arranging the deleted data packets as data segments in the data packets of the USB flow control unit is performed according to a preset rule.

[0043] The data segments in the data packets of the USB flow control unit are transmitted to the flow control packet processing module. According to the data segments in the data packets of the USB flow control unit, the flow control packet processing module calculates the CRC segment and the FEC segment, and splices the data segments in the data packets of the USB flow control unit with the CRC segment and the FEC segment to form the data packets of the USB flow control unit.

[0044] Furthermore, the data packet of the USB flow control unit is sent to the receiving end.

[0045] Further, for example, the data packet of the USB flow control unit can also be sent to the scrambling module to achieve the scrambling purpose. As for the specific implementation of scrambling, it belongs to the conventional means in this field and will not be repeated here.

[0046] Finally, the data packet of the USB flow control unit is sent to the receiving end.

[0047] Figure 5 It is a data processing flow chart of the present invention.

[0048] At the transmitting end, first, the data packet to be transmitted is taken out from the protocol layer or the link layer to obtain the deleted data packet, and then the data packet is arranged as data segments in the data packet of the USB flow control unit according to a preset rule.

[0049] Then, the CRC segment and the FEC segment are calculated according to the data segment in the data packet of the USB flow control unit, and the data segment, the CRC segment and the FEC segment in the data packet of the USB flow control unit are spliced ​​together to form the data packet of the USB flow control unit.

[0050] Preferably, the data packet of the USB flow control unit may be further scrambled to obtain a scrambled data packet.

[0051] The information processing flow at the receiving end is the reverse process of the information processing flow at the sending end. For example, the received scrambled data packet may be descrambled first, and then the descrambled data packet is sent to the logic sublayer of the receiving end for processing.

[0052] In the logic sublayer of the receiving end, the FEC segment in the descrambled data packet is first parsed to determine whether there is a data error during the transmission process. If there is, the error is directly corrected to obtain the corrected data. Then, the CRC segment in the descrambled data packet is used to determine whether the corrected data is correct. If the corrected data is correct, the corrected data is sent to the link layer and / or protocol layer of the receiving end for further parsing and processing.

[0053] The present invention eliminates the symbol encoding process in the USB system, uses a flow control encoding belonging to 1-bit to 1-bit encoding, and avoids bandwidth loss during USB data transmission.

[0054] In order to better illustrate the present invention, numerous specific details are provided in the above specific embodiments. It should be understood by those skilled in the art that the present invention can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0055] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for improving USB data transmission rate, characterized in that: In the logic sublayer of the transmitting end, a data packet from the link layer is received, and a packet tail and part of the synchronization segment in the data packet from the link layer are removed to obtain a deleted data packet; Arranging the deleted data packets into data segments in the data packets of the USB flow control unit according to a preset rule; Calculate the CRC segment and the FEC segment according to the data segment in the data packet of the USB flow control unit, and splice the data segment, the CRC segment and the FEC segment in the data packet of the USB flow control unit together to form a data packet of the USB flow control unit; Send the data packet of the USB flow control unit to the receiving end; In the logic sublayer of the sending end, a data packet from the protocol layer is also received, and a pruned data packet is obtained according to the data packet from the protocol layer; Before sending the data packet of the USB flow control unit to the receiving end, a scrambling operation is performed on the data packet of the USB flow control unit to obtain a scrambled data packet; At the receiving end, the scrambled data packet is first descrambled, and then the descrambled data packet is sent to the logical sublayer of the receiving end; In the logic sublayer of the receiving end, the FEC segment in the descrambled data packet is first parsed to determine whether there is a data error during the transmission process. If there is, error correction is performed directly to obtain the error-corrected data; The CRC segment in the descrambled data packet is used to determine whether the corrected data is correct. If the error-corrected data is correct, the error-corrected data is sent to the link layer and / or protocol layer of the receiving end.

2. A device for improving USB data transmission rate, characterized in that: The device for increasing the USB data transmission rate comprises a physical layer, the physical layer comprises a logical sublayer, and the logical sublayer comprises a flow control unit; The flow control unit includes an original packet processing module, a flow integration module and a flow control packet processing module; The original packet processing module receives the data packet from the link layer, and removes the packet tail and part of the synchronization segment in the data packet from the link layer to obtain a deleted data packet; The traffic integration module arranges the deleted data packets into data segments in the data packets of the USB traffic control unit according to a preset rule; The flow control packet processing module calculates the CRC segment and the FEC segment according to the data segment in the data packet of the USB flow control unit, and splices the data segment, the CRC segment and the FEC segment in the data packet of the USB flow control unit together to form a data packet of the USB flow control unit; The original packet processing module also receives a data packet from the protocol layer, and obtains a deleted data packet according to the data packet from the protocol layer; The device for increasing the USB data transmission rate is located in the sending end of the USB system.

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