METHOD AND SYSTEM FOR DATA TRANSFER

Description

[0001] The present invention relates to a method for transmitting data from a sender to a receiver. The invention also relates to a data transmission system comprising a sender for sending data and a receiver for receiving data.

[0002] Document DE 10 2018 006 988 B3 discloses a system and a method for data transmission using visible light. The system comprises a receiver with an image sensor whose light-sensitive area is scanned line by line, and a transmitter with a controllable light source that emits modulated light. An increased data transmission rate is achieved by utilizing the rolling shutter effect of the image sensor.

[0003] When data is transmitted bit by bit from a sender to a receiver, individual bits can be transmitted incorrectly. Error-detecting transmission methods are known to identify such errors. Furthermore, error-correcting transmission methods are known. In these methods, redundant parity bits are transmitted in addition to the data bits in a telegram. A cause of faulty data transmission is, for example, stochastic noise.

[0004] In bitwise data transmission from a sender to a receiver, individual bits can be lost, for example, when transmitting data as light from an LED as the sender to a camera with an image sensor as the receiver. The image sensor operates using the rolling shutter effect and alternates between an exposure time and a pause time. During the exposure time, an image can be captured; during the pause time, an image cannot be captured. Data transmitted to the receiver during the pause time cannot be received and is therefore lost.

[0005] Document US 2013 / 0051266 A1 discloses a method and a system for transmitting data from senders to receivers based on the IEEE802.16 standard.

[0006] Document US 2006 / 01 71418 A1 discloses a method and a device for transmitting data packets from senders to receivers via a transmission channel.

[0007] US patent 2019 / 0132000 A1 discloses a method for transmitting data from a sender to a receiver. In this method, a data frame is transmitted as a light stream from a light source to an optical camera.

[0008] Methods for transmitting data from a sender to a receiver are also known from US2005 / 0169392 A1 and DE 10 2010 031 411 A1.

[0009] The invention is based on the objective of further developing a method and a system for transmitting data from a sender to a receiver.

[0010] The problem is solved by a method for transmitting data with the features specified in claim 1. Advantageous embodiments and further developments are the subject of the dependent claims. The problem is also solved by a system for transmitting data with the features specified in claim 9. Advantageous embodiments and further developments are the subject of the dependent claims.

[0011] According to the inventive method for transmitting data from a sender to a receiver, the sender transmits at least one data frame comprising a plurality of data packets. Each data packet includes a packet number and a telegram, wherein the packet numbers of the data packets of the at least one data frame are different from one another, and wherein the telegrams of the data packets of the at least one data frame are identical.

[0012] The telegrams contain the data to be transmitted. Since several identical telegrams are transmitted within a data frame, the data is transmitted redundantly. If a telegram or part of a telegram is lost during the transmission of a data frame, the data contained in that telegram is additionally transmitted in other telegrams within the data frame and is thus available to the receiver. If the receiver has a pause, the time interval during which a data packet is sent should be at least as long as the aforementioned pause. Using the method according to the invention, data that is transmitted from the sender to the receiver, for example, during a receiver pause and is therefore lost, is nevertheless available to the receiver. Data loss during data transmission is thus advantageously avoided, and the range of the data transmission is increased.

[0013] According to the invention, the receiver receives a plurality of data packets of the at least one data frame in their entirety. This ensures that multiple telegrams with the same data are received by the receiver and that no data loss occurs. The reliability of the data transmission is thus increased.

[0014] According to the invention, the telegrams of the fully received data packets of the at least one data frame are summed to form a telegram sum of the at least one data frame. This results in a larger signal amplitude and advantageously increases the signal-to-noise ratio of the data to be transmitted. If individual data bits of a single telegram are corrupted due to noise, such errors are advantageously reduced or eliminated by summation.

[0015] According to the invention, the receiver determines the number of fully received data packets of the at least one data frame, and the telegram total of the at least one data frame is divided by the determined number. If individual data packets of data frames were not received, the telegram totals of the individual data frames each contain a different number of telegrams. Dividing by the determined number normalizes the telegram totals.

[0016] According to the invention, each of the data packets is sent within the same time period.

[0017] According to an advantageous embodiment of the invention, the packet numbers of the fully received data packets of the at least one data frame are added to form a number sum for the at least one data frame. If all data packets of the data frame are received by the receiver, the number sum is a known constant. If the number sum deviates from this constant, it is possible to determine from the deviation which of the data packets of the data frame was not received.

[0018] According to an advantageous embodiment of the invention, the packet numbers of the data packets of the at least one data frame are consecutive. This simplifies the determination of which of the data packets of the transmitted data frame has not been received.

[0019] According to an advantageous embodiment of the invention, each data packet of the at least one data frame comprises a start sequence, which includes at least one start bit. The start sequences of the data packets of the at least one data frame are identical. The start sequence makes it easier for the receiver to identify the beginning of a data packet within a data frame.

[0020] Preferably, the start sequence of a data packet is sent before the packet number and / or before the telegram of the data packet. This further facilitates the receiver's identification of the beginning of a data packet within a data frame.

[0021] According to an advantageous embodiment of the invention, each data packet of the at least one data frame comprises a stop sequence, which includes at least one stop bit. The stop sequences of the data packets of the at least one data frame are identical. The stop sequence makes it easier for the receiver to recognize the end of a data packet within a data frame.

[0022] Preferably, the stop sequence of a data packet is sent after the packet number of the data packet and / or after the telegram of the data packet. This further facilitates the receiver's identification of the end of a data packet within a data frame.

[0023] According to a preferred embodiment of the invention, the at least one data frame is transmitted as a light stream. A light stream is particularly EMC-compatible and, in particular, does not generate any radio signals that could have disruptive effects on other data transmission devices, such as WLAN antennas.

[0024] A system according to the invention for transmitting data comprises a transmitter for sending data and a receiver for receiving data. The system according to the invention is configured to carry out the method according to the invention.

[0025] The system according to the invention makes it possible to reconstruct data that is transmitted from the sender to the receiver and is lost in the process. Data loss during transmission is thus advantageously avoided.

[0026] It is advantageous if the time span in which one of the data packets of the at least one data frame is sent by the sender is at least as long as the receiver's pause time. In particular, if the receiver is a camera with an image sensor that operates using the rolling shutter effect and has a pause time, data transmitted during the receiver's pause time is still available to the receiver.

[0027] According to a preferred embodiment of the invention, the transmitter has a light source, and the receiver has an image sensor. Advantageously, at least one data frame can thus be transmitted as a light stream. A light stream is particularly EMC-compatible and, in particular, does not generate radio signals that could interfere with other data transmission devices, such as WLAN antennas.

[0028] According to an advantageous embodiment of the invention, the receiver comprises a lenticular film arranged between the light source of the transmitter and the image sensor. The lenticular film causes a light beam emitted by the light source to be projected onto the image sensor of the receiver not as a point, but as a stripe. An image sensor operating using the rolling shutter effect is scanned line by line. A data stream with a single data frame can be detected at a higher data transmission rate than the frame rate of the receiver's camera.

[0029] According to an advantageous embodiment of the invention, the transmitter is designed as an electronic device, in particular as a frequency converter, and has a controllable light source, in particular an LED.

[0030] According to a further advantageous embodiment of the invention, the transmitter is designed as a vehicle, in particular as an autonomously driving vehicle, and has a controllable light source, in particular an LED.

[0031] According to an advantageous embodiment of the invention, the receiver is designed as a mobile phone and includes a camera which has an image sensor.

[0032] The invention is not limited to the combination of features stated in the claims. For a person skilled in the art, further meaningful combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent, in particular from the problem statement and / or the problem arising from a comparison with the prior art.

[0033] The invention will now be explained in more detail with reference to the illustrations. The invention is not limited to the embodiments shown in the illustrations. The illustrations only depict the subject matter of the invention schematically. They show: Figure 1: a schematic representation of a system for transmitting data, Figure 2: a schematic representation of a data stream sent by a sender, and Figure 3: a schematic representation of a data stream received by a receiver.

[0034] Figure 1Figure 1 shows a schematic representation of a system 10 for data transmission. The data transmission system 10 comprises a transmitter 14, which has a controllable light source 1. The transmitter 14 is, for example, an electronic device, in particular a frequency converter, or a vehicle, in particular an autonomous vehicle. The light source 1 is, for example, an LED, by means of which the transmitter 14 sends data in the form of a luminous flux. It is also conceivable that the transmitter 14 is a ceiling lamp and the light source 1 is an associated light source.

[0035] The data transmission system 10 further comprises a receiver 12. The receiver 12 includes a camera which has an image sensor 2. The image sensor 2 operates using the rolling shutter effect. The receiver 12 is, for example, a standard mobile phone or smartphone. Data can be transmitted as a light stream from the transmitter 14 to the receiver 12 via the system 10. Optionally, the receiver 12 has a lenticular film which is arranged between the light source 1 of the transmitter 14 and the image sensor 2.

[0036] Figure 2Figure 1 shows a schematic representation of a data stream transmitted by a transmitter 14. The data stream comprises a first data frame FA, a second data frame FB, and a third data frame FC, which are transmitted sequentially. Each data frame FA, FB, FC comprises a first data packet P1, a second data packet P2, a third data packet P3, and a fourth data packet P4, which are transmitted sequentially. Each of the data packets P1, P2, P3, P4 is transmitted within the same time interval TS.

[0037] Receiver 12 alternates between an intake time (TR) and a pause time (TP). Data can be received during intake time (TR), but not during pause time (TP). Data transmitted to receiver 12 during pause time (TP) is therefore lost and cannot be received. The time interval (TS) during which a data packet P1, P2, P3, P4 is sent by sender 14 is longer than the pause time (TP) of receiver 12.

[0038] Each data packet P1, P2, P3, P4 of each data frame FA, FB, FC comprises a start sequence S, which has a defined sequence of start bits, a packet number N1, N2, N3, N4, and a telegram A, B, C. The start sequence S is the same for all data packets P1, P2, P3, P4 of all data frames FA, FB, FC and is sent before the packet numbers N1, N2, N3, N4 of the data packet P1, P2, P3, P4 and before the telegrams A, B, C of the data packet P1, P2, P3, P4. Optionally, each data packet P1, P2, P3, P4 also includes a stop sequence, which has a defined sequence of stop bits. The stop sequence is the same for all data packets P1, P2, P3, P4 of all data frames FA, FB, FC and is sent after the packet number N1, N2, N3, N4 of the data packet P1, P2, P3, P4 and after the telegram A, B, C of the data packet P1, P2, P3, P4.

[0039] The first data packet P1 of each data frame FA, FB, FC comprises a first packet number N1, here "I". The second data packet P2 of each data frame FA, FB, FC comprises a second packet number N2, here "II". The third data packet P3 of each data frame FA, FB, FC comprises a third packet number N3, here "III". The fourth data packet P4 of each data frame FA, FB, FC comprises a fourth packet number N4, here "IV". The packet numbers N1, N2, N3, N4 of the data packets P1, P2, P3, P4 of a data frame FA, FB, FC are sequential in this case.

[0040] Each data packet P1, P2, P3, P4 of the first data frame FA contains a first telegram A. Each data packet P1, P2, P3, P4 of the second data frame FB contains a second telegram B. Each data packet P1, P2, P3, P4 of the third data frame FC contains a third telegram C. Therefore, telegrams A, B, C of the data packets P1, P2, P3, P4 within a data frame FA, FB, FC are identical.

[0041] In this case, the pause time TP of receiver 12 occurs while the second data packet P2 of the second data frame FB is being sent by sender 14. Therefore, the second data packet P2 of the second data frame FB cannot be received by receiver 14 and is lost.

[0042] Figure 3 Figure 1 shows a schematic representation of a data stream received by receiver 12. This is the data stream shown in Figure 2. Figure 1 The data stream shown is sent by transmitter 14.

[0043] In this case, receiver 12 completely received all data packets P1, P2, P3, P4, i.e. four, of the first data frame FA.

[0044] The packet numbers N1, N2, N3, N4 of the fully received data packets P1, P2, P3, P4 of the first data frame FA are added together to form an initial number sum NA of the first data frame FA. From this initial number sum NA, receiver 12 determines the number of fully received data packets P1, P2, P3, P4 of the first data frame FA. In this case, that number is four.

[0045] The first telegrams A of data packets P1, P2, P3, P4 of the first data frame FA are added together to form a first telegram sum SA of the first data frame FA. This first telegram sum TA of the first data frame FA is then divided by the determined number, i.e., four.

[0046] In this case, receiver 12 completely received the first data packet P1, the third data packet P3, and the fourth data packet P4 of the second data frame FB. The second data packet P2 of the second data frame FB was not received but was lost.

[0047] The packet numbers N1, N3, N4 of the fully received data packets P1, P3, P4 of the second data frame FB are added together to form a second number sum NB of the second data frame FB. From this second number sum NB, receiver 12 determines the number of fully received data packets P1, P3, P4 of the second data frame FB. In this case, that number is three.

[0048] The second telegrams B of data packets P1, P3, P4 of the second data frame FB are added to form a second telegram sum SB of the second data frame FB. This second telegram sum TB of the second data frame FB is then divided by the determined number, i.e., three.

[0049] Furthermore, receiver 12 completely received a plurality of data packets P1, P2, P3, P4 of the third data frame FC.

[0050] The packet numbers N1, N2, N3, N4 of the fully received data packets P1, P2, P3, P4 of the third data frame FC are added together to form a third number sum NC of the third data frame FC (not shown here). From this third number sum NC, receiver 12 determines the number of fully received data packets P1, P2, P3, P4 of the third data frame FC. In this case, that number is between two and four.

[0051] The third telegrams C of the fully received data packets P1, P2, P3, P4 of the third data frame FC are added to a third telegram sum SC of the third data frame FC (not shown here). The third telegram sum TC of the third data frame FC is then divided by the determined number of telegrams. Reference symbol list

[0052] 1 Light source 2 Image sensor 10 System 12 Receiver 14 Transmitter A First telegram B Second telegram C Third telegram FA First data frame FB Second data frame FC Third data frame N1 First packet number N2 Second packet number N3 Third packet number N4 Fourth packet number NA First number sum NB Second number sum NC Third number sum P1 First data packet P2 Second data packet P3 Third data packet P4 Fourth data packet S Start sequence SA First telegram sum SB Second telegram sum SC Third telegram sum T P Pause time TR Recording time TS Time span

Claims

1. Method for transmitting bitwise data from a transmitter (14) to a receiver (12), the transmitter (14) sending at least one data frame (FA, FB, FC) which comprises a plurality of data packets (P1, P2, P3, P4), each data packet (P1, P2, P3, P4) comprising a packet number (N1, N2, N3, N4) and a telegram (A, B, C), the packet numbers (N1, N2, N3, N4) of the data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) being different from one another, and the telegrams (A, B, C) of the data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) being identical, and a plurality of data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) being received by the receiver (12) in their entirety, characterised in that the telegrams (A, B, C) of the entirely received data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) are added together bit by bit to form a telegram sum (SA, SB, SC) of the at least one data frame (FA, FB, FC), the receiver (12) establishes a number of entirely received data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC), and in that the telegram sum (SA, SB, SC) of the at least one data frame (FA, FB, FC) is divided by the established number bit by bit for the purpose of standardisation, and in that each of the data packets (P1, P2, P3, P4) is sent in the same time period (TS).

2. Method according to any of the preceding claims, characterised in that the packet numbers (N1, N2, N3, N4) of the entirely received data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) are added together to form a number sum (NA, NB, NC) of the at least one data frame (FA, FB, FC).

3. Method according to at least one of the preceding claims, characterised in that the packet numbers (N1, N2, N3, N4) of the data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) are continuous.

4. Method according to at least one of the preceding claims, characterised in that each data packet (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) comprises a start sequence (S) which has at least one start bit, the start sequences (S) of the data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) being identical.

5. Method according to claim 4, characterised in that the start sequence (S) of a data packet (P1, P2, P3, P4) is sent before the packet number (N1, N2, N3, N4) of the data packet (P1, P2, P3, P4) and / or before the telegram (A, B, C) of the data packet (P1, P2, P3, P4).

6. Method according to at least one of the preceding claims, characterised in that each data packet (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) comprises a stop sequence which has at least one stop bit, the stop sequences of the data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) being identical.

7. Method according to claim 6, characterised in that the stop sequence of a data packet (P1, P2, P3, P4) is sent after the packet number (N1, N2, N3, N4) of the data packet (P1, P2, P3, P4) and / or after the telegram (A, B, C) of the data packet (P1, P2, P3, P4).

8. Method according to at least one of the preceding claims, characterised in that the at least one data frame (FA, FB, FC) is transmitted as a light flux.

9. System (10) for transmitting data, comprising a transmitter (14) for sending data and a receiver (12) for receiving data, wherein the system is configured for carrying out the method according to at least one of the preceding claims.

10. System (10) according to claim 9, characterised in that a time period (TS) in which one of the data packets (P1, P2, P3, P4) of the at least one data frame (FA, FB, FC) is sent by the transmitter (14) is at least as long as a rest period (TP) of the receiver (12).

11. System (10) according to any of claims 9 to 10, characterised in that the transmitter (14) has a light source (1), and in that the receiver (12) has an image sensor (2).

12. System (10) according to claim 11, characterised in that the receiver (12) has a lenticular film which is arranged between the light source (1) of the transmitter (14) and the image sensor (2).