Techniques for increasing randomness between communication channels of multi-channel wired data communication link

Abstract

The invention relates to a device (200) for increasing randomness between different communication channels (231, 232) of a multi-channel wired data communication link (230). The apparatus (200) comprises a multi-channel data transmitter (210, 220) for simultaneously transmitting data over a first communication channel (231) and a second communication channel (232) of a multi-channel wired data communication link (230). The apparatus comprises a set of data scramblers (211, 221) for scrambling data prior to transmission of the data by a multi-channel data transmitter (210, 220). A first data scrambler (211) is used for scrambling data starting from a first seed signal (212) specifying an initial state of the first data scrambler (211). A second data scrambler (221) is configured to scramble data starting from a second seed signal (222) specifying an initial state of the second data scrambler (221). The first seed signal (212) and the second seed signal (222) are distinguished from each other by a predetermined signal distance measurement that increases randomness between data from the data scrambler set.

Description

Technical Field

[0001] The present invention relates to high-speed wired communication physical layer device (PHY) technology and multi-channel transmission for high-bandwidth applications, especially automotive applications. In particular, the present invention relates to technology for increasing randomness between communication channels of a multi-channel wired data communication link. More specifically, the present invention relates to scramblers and scrambler seed initialization for high-bandwidth transmission to achieve better data randomization. Background Art

[0002] Multi-channel high-speed wired communication PHY technology uses multiple channels to send data simultaneously to meet the growing bandwidth requirements, such as automotive applications. All existing technologies based on multi-channel communication use high-order polynomial scramblers to ensure that there is no data correlation between channels. This is very important to eliminate the inevitable crosstalk between channels. Recently, the IEEE802.3cy automotive standard adopted a 33-bit scrambler and a scrambler cycle of 0.6 seconds. Multi-channel PHY technology will deploy up to four channels to achieve a data rate of 100G bit / second (bit / s) and will replicate the same 33-bit scrambler for all channels. Taking into account the shorter scrambler cycle, the data stream from each channel will be correlated, such as Figure 1 As shown in Figure 2, they use the same 33-bit scrambler with a relatively short scrambler period. In this case, it is almost impossible to eliminate the crosstalk at the receiver for highly correlated data streams. Instead, very high-order polynomial scramblers can be used to eliminate the data correlation problem between channels. However, early research results clearly show that such high-order polynomial-based scramblers lead to poor transmit behavior. Therefore, there is a need to keep the order of the polynomial moderate and find schemes to improve the scrambler behavior to sufficiently randomize the data stream between channels. Summary of the invention

[0003] The present invention provides a solution to overcome the above crosstalk problem in multi-channel high-speed wired data communication. Specifically, a solution is proposed to increase the randomness between communication channels of a multi-channel wired data communication link.

[0004] The above and other objects are achieved by the features of the independent claims. Other implementations are apparent from the dependent claims, the description and the drawings.

[0005] The present invention proposes a concept to reduce the above crosstalk problem by improving the randomness between communication channels of a multi-channel wired data communication link.

[0006] In order to eliminate crosstalk noise at the receiver, it is very important to maintain sufficient randomization of the data stream between multiple channels. However, relatively low-order scrambling polynomials cannot guarantee this in all scenarios. Therefore, a scrambler seed initialization technique is proposed in the present invention to ensure that these seeds have sufficient distance ("far apart") relative to each other and the resulting data streams from these scramblers are sufficiently randomized. This initialization can be done at the beginning of link startup so that the phase difference between the scramblers is always maintained.

[0007] The gist of this new randomization concept can be described as follows:

[0008] a) a known scrambler seed that initializes the scrambler set at the beginning of the communication process between two PHYs;

[0009] b) ensuring that the value of the seed and its positioning results in maximizing data randomization between scrambler outputs;

[0010] c) The distance (phase) separation of the scrambler seeds depends on the number of communication channels;

[0011] d) For example, if there are two channels, then ideally the scrambler seeds need to be 180 degrees apart in phase. If there are four channels, then ideally the scrambler set seeds need to be 90 degrees apart in phase.

[0012] The concepts described in this invention can be applied to automotive applications using multi-channel data communications. Multi-channel transmission can be achieved through shielded or unshielded cables, twisted pair cables or coaxial cables. The concepts described here can be applied to PHY technology standards, such as the IEEE 802.3 series, including 1000BASE-T, 2.5GBASE-T, 5GBASE-T, 10GBASE-T and 40GBASE-T, especially the multi-channel standards 50GBASE-T2 (2 channels) and 100GBASE-T4 (4 channels).

[0013] The techniques described in this invention can be used as a standard using the public randomization and initialization concepts of the scrambler defined in the IEEE 802.3 standardization.

[0014] In addition to automotive, the technology described in this article can also be applied to industrial and automation applications, automotive in-vehicle networks, avionics, control and automation, etc.

[0015] The disclosed technique achieves better randomization data between different channels, making it easy to perform crosstalk cancellation. In addition, by keeping a relatively short scrambler period, the emission limit can be well controlled.

[0016] According to a first aspect, the present invention relates to an apparatus for increasing randomness between different communication channels of a multi-channel wired data communication link, the apparatus comprising: a multi-channel data transmitter for simultaneously transmitting data on a first communication channel and a second communication channel of the multi-channel wired data communication link; a set of data scramblers for scrambling data before the data is transmitted by the multi-channel data transmitter, a first data scrambler in the set of data scramblers being allocated for scrambling data for transmission on the first communication channel, and a second data scrambler in the set of data scramblers being allocated for scrambling data for transmission on the second communication channel; the first data scrambler being arranged to scramble data starting from a first seed signal specifying an initial state of the first data scrambler, the second data scrambler being arranged to scramble data starting from a second seed signal specifying an initial state of the second data scrambler, the first seed signal and the second seed signal being distinguishable from each other by a predetermined signal distance measure, the predetermined signal distance measure increasing randomness between data from the set of data scramblers.

[0017] Such an arrangement enables substantially increasing the randomness between the different communication channels of a multi-channel wired data communication link. This means that crosstalk can be effectively eliminated or at least significantly reduced at the receiver. This enables data to be sent at a higher data rate, since the crosstalk is reduced and does not interfere with signal reconstruction at the receiver.

[0018] The predetermined signal distance measure may be predetermined in such a way that it achieves optimal or maximum randomness between data from the set of data scramblers.

[0019] This increase in randomness between different communication channels helps to minimize crosstalk at the receiver.

[0020] In an exemplary implementation of the apparatus, the first seed signal and the second seed signal are predefined according to a predetermined signal distance measure.

[0021] This may achieve the advantage based on the knowledge that the receiver can optimally descramble the scrambled data.The predetermined signal distance measure enables sufficient or even optimal randomness between the different communication channels so that the crosstalk can be detected at the receiver and optimally cancelled by the receiver.

[0022] In an exemplary implementation of the apparatus, a signal distance measure is predetermined to enable data randomization between communication channels of a multi-channel data transmitter to minimize or at least reduce the effects of crosstalk or / and mitigate crosstalk by cancellation at the receiver if necessary.

[0023] This provides the advantage that there is sufficient data randomization between the communication channels of the multi-channel data transmitter, so the effects of crosstalk can be mitigated. If necessary, the receiver can eliminate or mitigate the crosstalk.

[0024] In an exemplary implementation of the apparatus, each data scrambler in the data scrambler set includes a linear feedback shift register and a scrambler polynomial defining an exclusive OR operation on the linear feedback shift register, and before initializing the multi-channel wired data communication link, each linear feedback shift register is initialized by a corresponding seed signal.

[0025] This provides the advantage that the linear feedback shift registers do not operate with the same seed signal, ie they have different seed signals, which provide sufficient randomization between the scrambled data. Thus, crosstalk effects can be reduced.

[0026] In an exemplary implementation of the apparatus, the first seed signal is associated with an initial state of a first linear feedback shift register, the second seed signal is associated with an initial state of a second linear feedback shift register, and the predetermined signal distance measure is based on a Hamming distance relative to the initial states of the first linear feedback shift register and the second linear feedback shift register.

[0027] This provides the advantage that the seed signals can be represented by their initial states. Therefore, the seed signals can be easily implemented as bytes or words that are designed to be separated by the Hamming distance. It should be understood that any other suitable metric can be used to separate the initial states.

[0028] In an exemplary implementation of the apparatus, the first seed signal and the second seed signal have different phases, the phases being predefined according to the predetermined signal distance measurement.

[0029] This offers the advantage that different phases can be easily illustrated by a phase diagram and different phases can be described within a scrambler period.

[0030] In an exemplary implementation of the apparatus, a phase difference between the first seed signal and the second seed signal is based on a number of communication channels of the multi-channel data transmitter.

[0031] This offers the advantage that a maximum distance can be applied for each seed signal.

[0032] In an exemplary implementation of the apparatus, a phase difference between the first seed signal and the second seed signal is within a threshold range of approximately 360 degrees divided by the number of communication channels, the 360 ​​degrees corresponding to a period of a data scrambler of the data scrambler set.

[0033] This provides the advantage that the value of 360 degrees / (number of communication channels) specifies the maximum distance between seed signals. However, not only is an exact value required, but even deviations from the exact value can still provide sufficient randomization between communication channels.

[0034] In an exemplary implementation of the apparatus, for a four-channel wired data communication link, a first seed signal of a first data scrambler associated with a first communication channel of the four-channel data transmitter corresponds to a phase of 45 degrees or a phase within a threshold range of about 45 degrees, a second seed signal of a second data scrambler associated with a second communication channel of the four-channel data transmitter corresponds to a phase of 135 degrees or a phase within a threshold range of about 135 degrees, a third seed signal of a third data scrambler associated with a third communication channel of the four-channel data transmitter corresponds to a phase of 225 degrees or a phase within a threshold range of about 225 degrees, and a fourth seed signal of a fourth data scrambler associated with a fourth communication channel of the four-channel data transmitter corresponds to a phase of 315 degrees or a phase within a threshold range of about 315 degrees.

[0035] This design of a four-lane wired data communication link provides optimal randomization among the four communication channels.

[0036] In an exemplary implementation of the apparatus, for a dual-channel wired data communication link, a first seed signal of a first data scrambler associated with a first communication channel of a dual-channel data transmitter corresponds to a phase of 90 degrees or a phase within a threshold range around 90 degrees, and a second seed signal of a second data scrambler associated with a second communication channel of the dual-channel data transmitter corresponds to a phase of 270 degrees or a phase within a threshold range around 270 degrees.

[0037] This design of a dual-channel wired data communication link provides optimal randomization between the two communication channels.

[0038] In an exemplary implementation of the apparatus, a set of data scramblers is used to decorrelate data of different communication channels of a multi-channel wired data communication link.

[0039] This provides the advantage that data from different communication channels is effectively decorrelated in order to provide sufficient randomization between the communication channels to effectively reduce or eliminate crosstalk at the receiver.

[0040] In an exemplary implementation of the apparatus, the set of data scramblers includes a self-synchronizing data scrambler for scrambling data without knowing the frame synchronization of the data.

[0041] This offers the advantage that no frame synchronization of the data is required, and the scrambling process is simple and fast.

[0042] In an exemplary implementation of the apparatus, the multi-channel data transmitter is used to transmit data according to 50GBASE-T2 and / or 100GBASE-T4 specifications.

[0043] This offers the advantage that these standards can be supported by the device.

[0044] In an exemplary implementation of the apparatus, the multi-channel data transmitter is configured to transmit data according to the IEEE 802.3cy standard.

[0045] According to the current version of the IEEE 802.3cy standard, data can be sent according to a 33-bit data scrambler, and the scrambler period is 613 milliseconds. It should be understood that higher versions of this standard may support other polynomials other than 33 bits (especially higher than 33 bits), for example, when a 33-bit implementation is too short.

[0046] This provides the advantage that this standard and later versions thereof can be supported by the device.

[0047] In an exemplary implementation of the apparatus, each data scrambler of the set of data scramblers includes an identical scrambler polynomial.

[0048] This offers the advantage that, by using the same scrambler polynomial, the data scramblers operate in the same way, only the respective seed signals differing.

[0049] In an exemplary implementation of the device, the device includes: a register set for storing a seed signal, each register being associated with a corresponding data scrambler of the data scrambler set; and a control channel for receiving a control signal, wherein the control signal is used to initialize a linear feedback shift register of the data scrambler with a corresponding seed signal stored in the register set when data transmission is initialized.

[0050] This provides the advantage that initialization of the data scrambler can be easily performed by using a control signal that triggers the initialization.

[0051] In an exemplary implementation of the apparatus, when the multi-channel data transmitter or a portion of the multi-channel data transmitter associated with transmission on the first communication channel is to enter a sleep mode, the first data scrambler continues to operate without entering a sleep mode.

[0052] This provides the advantage that the first data scrambler maintains the same phase difference with respect to the other data scramblers initialized at the beginning. Therefore, no phase desynchronization occurs which would negatively affect the correct randomization between the communication channels.

[0053] In an exemplary implementation of the apparatus, a first data scrambler enters a sleep mode upon receiving a sleep mode request; and upon receiving a wake-up request, the apparatus is configured to determine an actual state of all data scramblers and determine a first seed signal based on a read state of all data scramblers and a predetermined signal distance measurement.

[0054] This provides the advantage that a predetermined signal distance measure may be maintained between seed signals and therefore also optimal randomization between communication channels may be maintained after one or more scramblers have entered a sleep mode.

[0055] In an exemplary implementation of the apparatus, the apparatus includes a controller for reading actual states of all data scramblers upon receiving the sleep mode request; the controller for determining corresponding seed signals of the set of data scramblers based on the actual states of the data scramblers and the predetermined signal distance measurement.

[0056] This provides the advantage that the controller can be used to easily maintain a predetermined signal distance measurement between seed signals after a wake-up request.

[0057] In an exemplary implementation of the apparatus, the controller is configured to determine the corresponding seed signal according to the number of cycles between receiving the sleep mode request and receiving the wake-up request.

[0058] This provides the advantage that the controller can easily re-establish the initial state so that the predetermined signal distance measurement between the seed signals is maintained after a wake-up request including the next seed write synchronization cycle to the polynomial of the corresponding data scrambler.

[0059] According to a second aspect, the present invention relates to a method for increasing randomness between different communication channels of a multi-channel wired data communication link, the method comprising: simultaneously transmitting data on a first communication channel and a second communication channel of the multi-channel wired data communication link; scrambling the data by a set of data scramblers, a first data scrambler of the set of data scramblers being allocated for scrambling data for transmission over the first communication channel, and a second data scrambler of the set of data scramblers being allocated for scrambling data for transmission over the second communication channel, the first data scrambler scrambling the data starting from a first seed signal specifying an initial state of the first data scrambler, the second data scrambler scrambling the data starting from a second seed signal specifying an initial state of the second data scrambler, the first seed signal and the second seed signal being distinguishable from each other by a predetermined signal distance measure, the predetermined signal distance measure increasing the randomness between the data from the set of data scramblers.

[0060] Such a method provides the same advantages as the above-described apparatus. That is, the method enables the randomness between different communication channels of a multi-channel wired data communication link to be substantially increased. This means that crosstalk can be effectively eliminated or at least significantly reduced at the receiver. This enables data to be sent at a higher data rate without interfering with signal reconstruction at the receiver because the crosstalk is reduced.

[0061] This method for increasing randomness between different communication channels helps to minimize crosstalk at the receiver. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Other embodiments of the present invention will be described in conjunction with the following drawings, in which:

[0063] Figure 1 A schematic diagram showing a multi-channel wired data communication link 100 to which the concepts according to the present invention are not applied;

[0064] Figure 2 A block diagram of an apparatus 200 for increasing randomness between different communication channels according to the present invention is shown;

[0065] Figure 3 It is shown as Figure 2 A schematic diagram of an example of a phase difference 300 between data scramblers applied in the apparatus 200 shown;

[0066] Figure 4 It is shown that the application Figure 2 A schematic diagram of initialization 400 of exemplary data scramblers 410, 420 in the illustrated apparatus 200;

[0067] Figure 5 It is shown as Figure 4 Schematic diagram of an example of an initial state of the data scramblers 410, 420 shown;

[0068] Figure 6 A schematic diagram showing a method 600 for increasing randomness between different communication channels according to the present invention;

[0069] Figure 7 According to the first EEE mode embodiment, as shown Figure 2 The block diagram of the device 200 shown is in a normal operating mode 700a and an Energy Efficient Ethernet (EEE) mode 700b;

[0070] Figure 8 According to the second EEE mode embodiment, as shown Figure 2 A block diagram of the apparatus 200 is shown in EEE mode. DETAILED DESCRIPTION

[0071] In the following detailed description, reference is made to the accompanying drawings which form a part of this specification, wherein specific aspects of the present invention which may be practiced are illustrated by way of illustration. It should be understood that other aspects may be utilized, and structural or logical changes may be made without departing from the scope of the present invention. Therefore, the following specific embodiments should not be understood in a restrictive sense, and the scope of the present invention is defined by the appended claims.

[0072] It should be understood that comments related to the described method are also applicable to the corresponding device or system for performing the method, and vice versa. For example, if a specific method step is described, the corresponding device may include a unit for performing the described method step, even if such a unit is not elaborated or illustrated in detail in the figure. In addition, it should be understood that the features of the various exemplary aspects described herein can be combined with each other unless otherwise explicitly stated.

[0073] The devices described herein may be used to send and / or receive data via wired communication lines, for example, in accordance with IEEE 802.3 (including IEEE 802.3cy or IEEE 802.3ch). Wired transmission lines compliant with 10GBASE-T1, 25GBASE-T1, 50GBASE-T2, 100GBASE-T4, and other specifications may be used.

[0074] In the present invention, a multi-channel wired data communication link including multiple communication channels is described. Each communication channel is a separate communication link for data transmission. For example, such a communication channel can be a twisted pair, a coaxial cable, or any other suitable design. The multiple communication channels of the multi-channel wired data communication link can all share the same reference line, for example, have the same ground; or can include a dedicated reference line, for example, each communication channel can have a dedicated ground, or any combination thereof. Such a multi-channel wired data communication link can be used for high-speed communication, providing accurate and repeatable results. Such a multi-channel wired data communication link can be designed to have only minimal attenuation and signal distortion, and to operate efficiently over the frequency band of interest.

[0075] In the present invention, Energy Efficient Ethernet (EEE) mode is described. Energy Efficient Ethernet (EEE) mode is an optional operating mode that enables low power consumption when no data needs to be transmitted between two link partners. In this scenario, because there is nothing to transmit, one or more of the two link partners (for 50GBASE-T2) or one or more of the four link partners (for 100GBASE-T4) may request to enter "low power idle (LPI)" mode or "low power sleep" mode. When there is content to transmit, one of the link partners will receive a "wake-up" message and the link will wake up again from idle to normal operating mode to send data. In this scenario, when the link wakes up from "idle or deep sleep", the present invention proposes a scheme to ensure that the scrambler seed still maintains the same phase shift it was initialized with before the link was enabled.

[0076] Figure 1 A schematic diagram of a multi-channel wired data communication link 100 is shown without applying the concepts according to the present invention. The multi-channel wired data communication link 100 has four communication channels 121, 122, 123, 124, sending data from one PHY 120 to another PHY 110, where a device 111 acts as a receiver and sensitive device 111 of crosstalk 122a, 123a, 124a from adjacent communication channels 122, 123, 124.

[0077] All existing technologies based on multi-channel communication use high-order polynomial scramblers to ensure that there is no data correlation between channels. This is very important to eliminate the inevitable crosstalk between channels, such as Figure 1 As shown. Recently, in the IEEE802.3cy automotive application standard, a 33-bit scrambler is adopted, and the scrambler period is 0.6 seconds. Multi-channel PHY technology will deploy up to four channels 121, 122, 123, 124 to achieve a data rate of 100G bit / second, and the same 33-bit scrambler will be replicated for all channels.

[0078] Taking into account the short scrambler period, the data stream from each channel will be correlated, e.g. Figure 11 for the first communication channel 121, because they use the same 33-bit scrambler with a relatively short scrambler period. In this case, it is almost impossible to eliminate crosstalk at the receiver for highly correlated data streams. Instead, a very high-order polynomial scrambler can be used to eliminate the data correlation problem between channels. However, early research results clearly show that such high-order polynomial-based scramblers can lead to poor transmission behavior. Therefore, it is necessary to keep the order of the polynomial moderate and find other solutions to improve the scrambler behavior to fully randomize the data stream between channels.

[0079] An alternative approach that may achieve better randomization is described below.

[0080] Figure 2 A block diagram of an apparatus 200 for increasing randomness between different communication channels 231 , 232 of a multi-channel wired data communication link 230 according to the present invention is shown.

[0081] The apparatus 200 comprises multi-channel data transmitters 210 , 220 for simultaneously transmitting data on a first communication channel 231 and a second communication channel 232 of a multi-channel wired data communication link 230 .

[0082] The apparatus 200 includes a data scrambler set 211, 221 for scrambling data before the multi-channel data transmitter 210, 220 transmits the data. A first data scrambler 211 in the data scrambler set 211, 221 is allocated to scramble data for transmission on a first communication channel 231. A second data scrambler 221 in the data scrambler set 211, 221 is allocated to scramble data for transmission on a second communication channel 232.

[0083] The first data scrambler 211 is used to scramble data starting from a first seed signal 212 that specifies an initial state of the first data scrambler 211 .

[0084] The second data scrambler 221 is used to scramble data starting from a second seed signal 222 that specifies an initial state of the second data scrambler 221 .

[0085] The first seed signal 212 and the second seed signal 222 are distinguished from each other by a predetermined signal distance measure. The predetermined signal distance measure is designed to increase randomness between data from the set of data scramblers.

[0086] The predetermined signal distance measure may be predetermined in such a way that it achieves optimal or maximum randomness between data from the set of data scramblers.

[0087] This increase in randomness between different communication channels helps to minimize crosstalk at the receiver.

[0088] The first seed signal 212 and the second seed signal 222 may be predefined according to a predetermined signal distance measurement.

[0089] The signal distance measurement may be predetermined so that the data between the communication channels 231, 232 of the multi-channel data transmitters 210, 220 can be randomized, thereby minimizing or at least reducing the effects of the crosstalk 122a, 123a, 124a, such as Figure 1 as shown; or / and if necessary, to mitigate crosstalk by cancellation at the receiver, for example, as Figure 1 As shown, at PHY 110 .

[0090] Each data scrambler of the data scrambler set 211, 221 may include a linear feedback shift register 410, 420, such as Figure 4 As shown in FIG. 4 , and a scrambler polynomial defining the XOR operation on the linear feedback shift registers 410 and 420. Before the multi-channel wired data communication link 230 is initialized, that is, before the line is turned on, each linear feedback shift register 410 and 420 can be initialized by a corresponding seed signal 212 and 222.

[0091] For example, for 10GBASE-T, the host (i.e., transmitter) can use the polynomial: 1+X 39 +X 58 ; The slave (such as a receiver) can use the polynomial: 1+X 19 +X 58 For 1000BASE-T1, the host can use the polynomial: 1+X 4 +X 15 , and the slave can use the polynomial: 1+X 11 +X 15 For 1000BASE-T, the host can use the polynomial: 1+X 13 +X 33 , and the slave can use the polynomial: 1+X 20 +X 33 .

[0092] The first seed signal 212 may be associated with an initial state of the first linear feedback shift register 410 and the second seed signal 222 may be associated with an initial state of the second linear feedback shift register 420. The predetermined signal distance measure may be based on a Hamming distance or any other metric relative to the initial states of the first linear feedback shift register 410 and the second linear feedback shift register 420.

[0093] The first seed signal 212 and the second seed signal 222 may be designed to have different phases, for example Figure 3 The phase may be predefined based on a predetermined signal distance measurement.

[0094] The phase difference 320 between the first seed signal 212 and the second seed signal 222 may be based on the number of communication channels 231, 232 of the multi-channel data transmitters 210, 220, for example. Figure 3 An example of a 4-channel communication link is shown.

[0095] The phase difference 320 between the first seed signal 212 and the second seed signal 222 may be within a threshold range of approximately 360 degrees divided by the number of communication channels 231, 232, such as Figure 3 360 degrees corresponds to a period 310 of the data scramblers 211 and 221 of the data scrambler set. Figure 3 In the example shown, this period is 613 milliseconds.

[0096] In one exemplary implementation, a four-channel wired data communication link 230 may be used. Then, the first seed signal 301 of the first data scrambler 211 associated with the first communication channel of the four-channel data transmitter may correspond to a phase of 45 degrees or a phase within a threshold range around 45 degrees, such as Figure 3 The second seed signal 302 of the second data scrambler 221 associated with the second communication channel of the four-channel data transmitter may correspond to a phase of 135 degrees or a phase within a threshold range around 135 degrees, such as Figure 3 The third seed signal 303 of the third data scrambler associated with the third communication channel of the four-channel data transmitter may correspond to a phase of 225 degrees or a phase within a threshold range around 225 degrees, such as Figure 3 The fourth seed signal 304 of the fourth data scrambler associated with the fourth communication channel of the four-channel data transmitter may correspond to a phase of 315 degrees or a phase within a threshold range around 315 degrees, such as Figure 3 shown.

[0097] For example, the threshold ranges may be within + / -1°, + / -2°, + / -3°, + / -5°, + / -10°, + / -15°, + / -20°, + / -25°, + / -30° of the corresponding phase. It should be understood that other suitable ranges and asymmetric ranges are also applicable.

[0098] In another exemplary implementation, a dual-channel wired data communication link 230 may be used. In this implementation, a first seed signal of a first data scrambler 211 associated with a first communication channel of a dual-channel data transmitter may correspond to a phase of 90 degrees or a phase within a threshold range around 90 degrees. A second seed signal of a second data scrambler 221 associated with a second communication channel of the dual-channel data transmitter may correspond to a phase of 270 degrees or a phase within a threshold range around 270 degrees.

[0099] For example, the threshold ranges may be within + / -1°, + / -2°, + / -3°, + / -5°, + / -10°, + / -15°, + / -20°, + / -25°, + / -30°, + / -35°, + / -40°, + / -50°, + / -60° of the corresponding phase. It should be understood that other suitable ranges and asymmetric ranges are also applicable.

[0100] Such a dual-channel wired data communication link 230 can also be based on Figure 3 The example of , in which the seed signals corresponding to phases 135 degrees and 315 degrees are removed. Then, the first seed signal may correspond to a phase of 45 degrees, and the second seed signal may correspond to a phase of 225 degrees, both separated by 180 degrees.

[0101] The data scrambler sets 211 , 221 may be used to decorrelate data of different communication channels 231 , 232 of the multi-channel wired data communication link 230 .

[0102] The data scrambler set 211, 221 may include a self-synchronizing data scrambler for scrambling data without knowing the frame synchronization of the data.

[0103] A self-synchronous scrambler is a multiplicative scrambler (also called a feedthrough) that performs a multiplication of the input signal in Z space by the scrambler's transfer function, e.g. Figure 4 As shown. They are discrete linear time-invariant systems. Multiplicative scramblers are recursive and multiplicative descramblers are non-recursive. Unlike additive scramblers, multiplicative scramblers do not require frame synchronization, which is why they are also called self-synchronizing. Similarly, a multiplicative scrambler / descrambler is defined by a polynomial, which is also the transfer function of the descrambler.

[0104] In one exemplary implementation, the multi-channel data transmitters 210, 220 may be used to transmit data in accordance with 50GBASE-T2 and / or 100GBASE-T4 specifications.

[0105] In one exemplary implementation, the multi-channel data transmitters 210, 220 may be used to transmit data according to the IEEE 802.3cy standard.

[0106] According to the current version of the IEEE 802.3cy standard, data can be sent according to a 33-bit data scrambler, and the scrambler period is 613 milliseconds. It should be understood that higher versions of this standard may support other polynomials other than 33 bits (especially higher than 33 bits), for example, when a 33-bit implementation is too short.

[0107] Each data scrambler of the data scrambler set 211, 221 may include the same scrambler polynomial.

[0108] The apparatus 200 may further include: register sets 411, 421, for example, Figure 4 As shown, the registers are used to store seed signals 212, 222. Each register may be associated with a corresponding data scrambler in the data scrambler set 211, 221.

[0109] The apparatus 200 may include a control channel for receiving a control signal 401, such as Figure 4 The control signal 401 can be used to initialize the linear feedback shift registers 410, 420 of the data scramblers 211, 221 with the corresponding seed signals 212, 222 stored in the register sets 411, 421 when the data transmission 230 is initialized.

[0110] Figure 3 It is shown as Figure 2 A schematic diagram of an example of a phase difference 300 between data scramblers applied in the apparatus 200 is shown.

[0111] Figure 3 The example of FIG. 2 shows a four-lane wired data communication link 230. For example, Figure 2 As shown, the first seed signal 301 of the first data scrambler 211 associated with the first communication channel 231 of the four-channel data transmitter can correspond to a phase of 45 degrees or a phase within a threshold range around 45 degrees. For example, such a threshold range can be within + / -1°, + / -2°, + / -3°, + / -5°, + / -10°, + / -15°, + / -20°, + / -25°, + / -30° of the 45° phase.

[0112] For example, Figure 2 As shown, the second seed signal 302 of the second data scrambler 221 associated with the second communication channel 232 of the four-channel data transmitter can correspond to a phase of 135 degrees or a phase within a threshold range around 135 degrees. For example, such a threshold range can be within + / -1°, + / -2°, + / -3°, + / -5°, + / -10°, + / -15°, + / -20°, + / -25°, + / -30° of the 135° phase.

[0113] The third seed signal 303 of the third data scrambler associated with the third communication channel of the four-channel data transmitter may correspond to a phase of 225 degrees or a phase within a threshold range around 225 degrees. For example, such a threshold range may be within + / -1°, + / -2°, + / -3°, + / -5°, + / -10°, + / -15°, + / -20°, + / -25°, + / -30° of the phase of 225°.

[0114] The fourth seed signal 304 of the fourth data scrambler associated with the fourth communication channel of the four-channel data transmitter may correspond to a phase of 315 degrees or a phase within a threshold range around 315 degrees, such as Figure 3 For example, such a threshold range may be within + / -1°, + / -2°, + / -3°, + / -5°, + / -10°, + / -15°, + / -20°, + / -25°, + / -30° of a 315° phase.

[0115] In this example of a four-lane wired data communication link 230 , each seed signal has a phase difference 320 of 90°.

[0116] Figure 3 It is shown that it is very important to keep the data stream sufficiently randomized between multiple channels in order to eliminate crosstalk noise at the receiver. However, relatively low-order scrambling polynomials cannot guarantee this in all scenarios. Therefore, a Figure 3 The disclosed scrambler seed initialization technique is exemplarily shown for a four-lane wired data communication link 230 to ensure that the seeds are sufficiently distant (“far apart”) relative to each other and the resulting data streams from the scramblers are sufficiently randomized. This initialization can be done at the beginning of link startup so that the phase difference between the scramblers is always maintained.

[0117] Figure 4 It is shown that the application Figure 2 A schematic diagram of initialization 400 of exemplary data scramblers 410 , 420 in the apparatus 200 is shown.

[0118] Figure 4 Scramblers 410, 420 are shown, which are linear feedback shift registers. According to the definition of the scrambler polynomial, the XOR operation is performed accordingly. In addition, depending on the number of channels available for a particular wire-based communication technology, the seed for the corresponding scrambler 410, 420, i.e., Figure 2The described initialization 401 of the seed signals 212, 222 is predetermined and stored in registers 411, 421. Each time before the communication link is established, the contents of the registers 411, 421 are loaded into the respective scramblers 410, 420. If necessary, a test can be performed to ensure that the scrambler set generates sufficiently random data.

[0119] The phase difference between the seeds 212, 222 of the scramblers 410, 420 depends on the number of channels. For example, a phase difference corresponding to 360 degrees / number of channels may be applied.

[0120] In one embodiment, the phase separation between seeds is ideal. For example, for a wire-based four-channel communication technology, the spacing of the scrambler seeds is exactly 90 degrees. Based on the phase separation, the seed content will be calculated and stored in registers 411, 421.

[0121] This phase separation allows for excellent randomization of the data from the scrambler sets 410, 420.

[0122] In another embodiment, the phase separation between the seeds may be slightly different from the ideal value. For example, in the case of a four-channel based wired communication technology, the ideal phase difference is 90 degrees, however, for practical reasons, the phase difference between the scramblers may be slightly less than 90 degrees or slightly more than 90 degrees.

[0123] The size of the scrambler polynomial is not limited to a certain number. A technique can be applied that estimates the scrambler seed separation based on the phase (degrees) or distance (milliseconds) and the corresponding content of each scrambler, thus being able to provide sufficiently random data at the output of the scrambler.

[0124] This phase separation allows the data from the scrambler sets 410, 420 to be fully randomized.

[0125] In other embodiments, the scrambler seed phase difference or distance interval in milliseconds may be changed (varied) to some extent until the random behavior between the scrambler 410, 420 outputs begins to become poor.

[0126] Even with this phase separation, the data from the scrambler sets 410, 420 is still sufficiently randomized.

[0127] Figure 5 It is shown as Figure 4 Schematic diagram of an example of an initial state of the data scramblers 410, 420 is shown.

[0128] In a four-channel communication link, the first seed signal, e.g. Figure 2The seed signal 212 shown may be associated with the initial state of the first linear feedback shift register 410, for example Figure 4 The initial state of the first linear feedback shift register 410 may be "0001", for example, Figure 5 The second seed signal may be associated with an initial state of the second linear feedback shift register. The initial state of the second linear feedback shift register may be "0101", for example, Figure 5 The third seed signal may be associated with an initial state of the third linear feedback shift register. The initial state of the third linear feedback shift register may be "1001", for example, Figure 5 The fourth seed signal may be associated with an initial state of a fourth linear feedback shift register. The initial state of the fourth linear feedback shift register may be "1011", for example, Figure 5 shown.

[0129] Figure 6 The method for increasing the multi-channel wired data communication link 230 (such as Figure 2 Schematic diagram of method 600 for randomness between different communication channels (as shown).

[0130] Method 600 includes: Figure 2 As described above, data is sent 601 simultaneously through the first communication channel 231 and the second communication channel 232 of the multi-channel wired data communication link.

[0131] The method 600 includes scrambling 602 data by a set of data scramblers, wherein a first data scrambler 211 of the set of data scramblers 211, 221 is allocated for scrambling data for transmission via a first communication channel 231, and a second data scrambler 221 of the set of data scramblers 211, 221 is allocated for scrambling data for transmission via a second communication channel 232, e.g., as described above with respect to Figure 2 As described, the first data scrambler 211 starts scrambling data from a first seed signal 212 that specifies an initial state of the first data scrambler 211, and the second data scrambler 221 starts scrambling data from a second seed signal 222 that specifies an initial state of the second data scrambler 221, and the first seed signal 212 and the second seed signal 222 are distinguished from each other by a predetermined signal distance measurement, and the predetermined signal distance measurement increases randomness between the data from the data scrambler set.

[0132] This method for increasing randomness between different communication channels helps to minimize crosstalk at the receiver.

[0133] Figure 7 According to the first embodiment, Figure 2 The illustrated block diagram of the apparatus 200 is in a normal operating mode 700a and an Energy Efficient Ethernet (EEE) mode 700b.

[0134] In the figure above, if Figure 2 As shown, a multi-channel wired data communication link is shown in a normal operating mode 700a between two devices 200. Each communication channel 231, 232, 233, 234 between two corresponding PHYs 210, 220, 230, 240 is connected, ie, operating in normal mode.

[0135] In the figure below, the multi-channel wired data communication link is shown in EEE mode 700b. In this example, the fourth communication channel 234 will be dormant, that is, in EEE mode, while the other communication channels 231, 232, 233 are still connected, that is, working in normal operation mode.

[0136] This represents only one example of EEE mode. In other examples, the first communication channel 231 may be in sleep mode, while the other communication channels 232, 233, 234 may be in sleep mode or idle mode, i.e. in EEE mode. Any combination of on and sleep or idle modes of different communication channels is possible, for example, three communication channels are in sleep or idle mode and one communication channel is in on or normal mode, or two communication channels are in sleep or idle mode and the other two communication channels are in on or normal mode.

[0137] With respect to the above figure, all four PHYs 210, 220, 230, 240 go through a startup process by initializing scrambler seeds that are spaced far enough apart to maintain good data randomization between lanes, e.g., as described above with respect to Figure 2 After the link performs normal data transmission, one or more of the link partners receive a request to enter a "low power sleep" or "low power idle" mode. This request will be sent to one or more link partners at the other end, and then the specific link enters a low power idle or low power sleep mode, such as Figure 7 as shown in the lower diagram.

[0138] After a certain time interval, one of the link partners can receive a wake-up message and the message will be sent to the other partner. Once the dormant or idle PHY enters normal data mode, the scrambler seed should maintain the same phase difference as when it was initialized at the beginning. The present invention presents the above about Figure 2 Two embodiments of the apparatus 200 are described to maintain the same phase difference as when initializing after entering normal data mode.

[0139] according to Figure 7 In the first embodiment shown, the data scrambler must not enter a sleep mode during a low power idle or low power sleep mode.

[0140] While a PHY or a PHY set is in sleep mode or idle mode, its or their data scrambler 211, 221 (see Figure 2 ) must run continuously in order to maintain the same phase difference between the data scramblers 211, 221.

[0141] Figure 8 According to the second embodiment, Figure 2 A block diagram of the apparatus 200 is shown in EEE mode.

[0142] Figure 8 It is shown that in the EEE mode according to the second embodiment, as shown in FIG. Figure 2 The multi-channel wired data communication link between the two devices 200 is shown. In this example, the fourth communication channel 234 is dormant, that is, in the EEE mode, while the other communication channels 231, 232, 233 are still in the on state, that is, working in the normal operation mode.

[0143] In this second embodiment, during a low power idle or low power sleep mode, the data scrambler will enter a sleep mode.

[0144] Once the PHY receives a wake-up request, it reads all scrambler states and calculates the corresponding required phase difference only for the PHY in idle or sleep mode. Figure 2 The seed signals 212, 222 will be initialized again for those PHYs that disappeared due to "idle" or "sleep".

[0145] Once the seed is reinitialized, only these PHYs and corresponding link partners will enter training or full data transmission.

[0146] In the following, exemplary functions of the apparatus 200 are described.

[0147] In the device 200, the first data scrambler 211 may enter the sleep mode upon receiving the sleep mode request. Upon receiving the wake-up request, the device 200 may be configured to determine the actual status of all data scramblers and determine the first seed signal 212 based on the read status of all data scramblers and a predetermined signal distance measurement.

[0148] The apparatus 200 may include a controller 811 for, upon receiving a sleep mode request, reading an actual state 812 of all data scramblers 211, 221, 231, 241. The controller 811 may be configured to determine a corresponding seed signal 212, 222, 232, 242 of a set of data scramblers based on the actual state 812 of the data scramblers 211, 221, 231, 241 and a predetermined signal distance measurement.

[0149] The controller 811 may be configured to receive a sleep mode request and receive a scrambler polynomial (eg, as described above with respect to the scrambler polynomial) including the next seed write synchronization cycle to the corresponding data scrambler 211, 221, 231, 241. Figure 4 The number of cycles between wake-up requests of the scrambler polynomial) determines the corresponding seed signals 212, 222, 232, 242.

[0150] Although specific features or aspects of the present invention may have been disclosed in conjunction with only one of several implementations, such features or aspects may be combined with one or more features or aspects in other implementations, as long as it is necessary or advantageous for any given or specific application. In addition, to a certain extent, the terms "including", "having", "having" or other variations of these words are used in the specific embodiments or claims, and such terms are similar to the term "including" and are both intended to include. Similarly, the terms "exemplary" and "for example" are only represented as examples, not the best or optimal. The terms "coupled" and "connected" and derivatives may be used. It should be understood that these terms can be used to indicate that two elements cooperate or interact with each other, regardless of whether they are in direct physical contact or electrical contact, or they are not in direct contact with each other.

[0151] Although specific aspects have been illustrated and described herein, it will be appreciated by those skilled in the art that a variety of alternative and / or equivalent implementations may be substituted for the specific aspects shown and described without departing from the scope of the invention. This application is intended to cover any modifications or changes to the specific aspects discussed herein.

[0152] Although the elements in the above claims are listed in a specific order with corresponding labels, these elements are not necessarily limited to being implemented in this specific order unless the recitation of the claims otherwise implies a specific order for implementing some or all of these elements.

[0153] According to the above guidance, many substitutions, modifications and changes are obvious to those skilled in the art. Of course, it is easy for those skilled in the art to recognize that, in addition to the applications described herein, there are many other applications of the present invention. Although the present invention has been described with reference to one or more specific embodiments, it is recognized by those skilled in the art that many changes can be made to it without departing from the scope of the present invention. Therefore, it should be understood that, as long as it is within the scope of the attached claims and their equivalents, the present invention can be practiced in a manner different from that specifically described herein.

Claims

1. A device (200) for increasing randomness between different communication channels (231, 232) of a multi-channel wired data communication link (230), the device (200) comprising: A multi-channel data transmitter (210, 220) for simultaneously transmitting data on a first communication channel (231) and a second communication channel (232) of the multi-channel wired data communication link (230); a data scrambler set (211, 221) for scrambling the data before the multi-channel data transmitter (210, 220) transmits the data, a first data scrambler (211) in the data scrambler set (211, 221) being allocated for scrambling the data for transmission via a first communication channel (231), and a second data scrambler (221) in the data scrambler set (211, 221) being allocated for scrambling the data for transmission via a second communication channel (232); The first data scrambler (211) is used to scramble data starting from a first seed signal (212) that specifies an initial state of the first data scrambler (211); The second data scrambler (221) is used to scramble data starting from a second seed signal (222) that specifies an initial state of the second data scrambler (221); The first seed signal (212) and the second seed signal (222) are distinguishable from each other by a predetermined signal distance measure that increases randomness between data from the set of data scramblers.

2. The device (200) according to claim 1, characterized in that: The first seed signal (212) and the second seed signal (222) are predefined according to the predetermined signal distance measurement.

3. The device (200) according to claim 1 or 2, characterized in that: The signal distance measurement is predetermined to enable data randomization between the communication channels (231, 232) of the multi-channel data transmitter (210, 220) to minimize or at least reduce the effects of crosstalk (122a, 123a, 124a) and / or mitigate the crosstalk by cancellation at the receiver if necessary.

4. The device (200) according to any one of the preceding claims, characterized in that: Each data scrambler in the data scrambler set (211, 221) comprises a linear feedback shift register (410, 420) and a scrambler polynomial defining an exclusive-OR operation on the linear feedback shift register (410, 420), wherein each linear feedback shift register (410, 420) is initialized by a corresponding seed signal (212, 222) before a multi-channel wired data communication link (230) is initialized.

5. The device (200) according to claim 4, characterized in that: The first seed signal (212) is associated with an initial state of a first linear feedback shift register (410), and the second seed signal (222) is associated with an initial state of a second linear feedback shift register (420), and the predetermined signal distance measure is based on a Hamming distance relative to the initial states of the first linear feedback shift register (410) and the second linear feedback shift register (420).

6. The device (200) according to any one of the preceding claims, characterized in that: The first seed signal (212) and the second seed signal (222) have different phases, the phases being predefined according to the predetermined signal distance measurement.

7. The device (200) according to claim 6, characterized in that: A phase difference (320) between the first seed signal (212) and the second seed signal (222) is based on the number of communication channels (231, 232) of the multi-channel data transmitter (210, 220).

8. The device (200) according to claim 7, characterized in that: A phase difference (320) between the first seed signal (212) and the second seed signal (222) is within a threshold range of approximately 360 degrees divided by the number of the communication channels (231, 232); The 360 ​​degrees corresponds to a period (310) of the data scrambler (211, 221) of the data scrambler set.

9. The device (200) according to any one of the preceding claims, characterized in that For a four-channel wired data communication link (230): A first seed signal (301) of a first data scrambler (211) associated with a first communication channel of the four-channel data transmitter corresponds to a phase of 45 degrees or a phase within a threshold range of about 45 degrees; A second seed signal (302) of a second data scrambler (221) associated with a second communication channel of the four-channel data transmitter corresponds to a phase of 135 degrees or a phase within a threshold range of about 135 degrees; A third seed signal (303) of a third data scrambler associated with a third communication channel of the four-channel data transmitter corresponds to a phase of 225 degrees or a phase within a threshold range around 225 degrees; A fourth seed signal (304) of a fourth data scrambler associated with a fourth communication channel of the four-channel data transmitter corresponds to a phase of 315 degrees or a phase within a threshold range about 315 degrees.

10. The device according to any one of the preceding claims, characterized in that For a dual-channel wired data communications link: A first seed signal of a first data scrambler (211) associated with a first communication channel of the dual channel data transmitter corresponds to a phase of 90 degrees or a phase within a threshold range of about 90 degrees; A second seed signal of a second data scrambler (221) associated with a second communication channel of the dual channel data transmitter corresponds to a phase of 270 degrees or a phase within a threshold range around 270 degrees.

11. The device (200) according to any one of the preceding claims, characterized in that: The data scrambler set (211, 221) is used to decorrelate data of different communication channels (231, 232) of the multi-channel wired data communication link (230).

12. The device (200) according to any one of the preceding claims, characterized in that: The data scrambler set (211, 221) includes a self-synchronizing data scrambler for scrambling the data without knowing the frame synchronization of the data.

13. The device (200) according to any one of the preceding claims, characterized in that: The multi-channel data transmitter (210, 220) is used to transmit data according to 50GBASE-T2 and / or 100GBASE-T4 specifications.

14. The device (200) according to any one of the preceding claims, characterized in that: The multi-channel data transmitter (210, 220) is used to transmit data according to the IEEE 802.3cy standard.

15. The device (200) according to claim 4 or 5, characterized in that: Each data scrambler in the set of data scramblers (211, 221) includes the same scrambler polynomial.

16. The device (200) according to claim 15, characterized in that include: a register set (411, 421) for storing a seed signal (212, 222), each register being associated with a respective data scrambler of the data scrambler set (211, 221); A control channel for receiving a control signal (401), wherein the control signal (401) is used to initialize the linear feedback shift registers (410, 420) of the data scrambler (211, 221) with corresponding seed signals (212, 222) stored in the register set (411, 421) when data transmission (230) is initialized.

17. The device (200) according to any one of the preceding claims, characterized in that: When the multi-channel data transmitter (210, 220) or a portion of the multi-channel data transmitter (210, 220) associated with transmission through the first communication channel (231) enters a sleep mode, the first data scrambler (211) continues to operate without entering a sleep mode.

18. The device (200) according to any one of claims 1 to 16, characterized in that: The first data scrambler (211) enters a sleep mode upon receiving a sleep mode request; Upon receiving the wake-up request, the apparatus is configured to determine the actual status of all data scramblers and determine a first seed signal based on the read status of all data scramblers and a predetermined signal distance measurement (212).

19. The device (200) according to claim 18, characterized in that: comprising a controller (811) for reading the actual status (812) of all data scramblers (211, 221, 231, 241) upon receiving a sleep mode request; The controller (811) is used to determine the corresponding seed signal (212, 222, 232, 242) of the set of data scramblers based on the actual state (812) of the data scramblers (211, 221, 231, 241) and the predetermined signal distance measurement.

20. The device (200) according to claim 19, characterized in that: The controller (811) is used to determine a corresponding seed signal (212, 222, 232, 242) based on the number of cycles between receiving the sleep mode request and receiving the wake-up request including a next seed write synchronization cycle for the scrambler polynomial of the corresponding data scrambler.

21. A method (600) for increasing randomness between different communication channels of a multi-channel wired data communication link (230), the method (600) comprising: Simultaneously sending (601) data on a first communication channel (231) and a second communication channel (232) of the multi-channel wired data communication link; scrambling the data (602) by a data scrambler set, a first data scrambler (211, 221) of the data scrambler set (211) being allocated for scrambling data for transmission via a first communication channel (231), and a second data scrambler (221) of the data scrambler set (211, 221) being allocated for scrambling data for transmission via a second communication channel (232); The first data scrambler (211) scrambles the data starting from a first seed signal (212) that specifies an initial state of the first data scrambler (211); The second data scrambler (221) scrambles the data starting from a second seed signal (222) that specifies an initial state of the second data scrambler (221); The first seed signal (212) and the second seed signal (222) are distinguishable from each other by a predetermined signal distance measure that increases randomness between data from the set of data scramblers.

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