A congestion mitigation data readout system and method

Abstract

The present invention discloses a congestion mitigation data reading system, comprising: first, data of each channel is synchronized by a data receiving module and then transmitted to a congestion mitigation module after appending address information; each congestion mitigation module is connected to two data structure modules with an interval of four channels, and caches the transmitted data according to a handshake protocol; a continuous arbitration module selects a certain congestion mitigation module to cache data for transmission according to the empty / full information until the cache space is empty; finally, a cyclic arbitration module cyclically selects the data outputs of each continuous arbitration module. This system enables two channels with an interval of four channels to share a storage space, and selects data for transmission through two arbitration methods, namely continuous and cyclic, which can effectively alleviate the situation of data congestion caused by a large amount of data that needs to be output simultaneously by front-end sensors, and improve the data transmission efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of radiation detection, and more particularly to a congestion mitigation data readout system and method. Background Art

[0002] In the field of radiation detection, a large amount of data is generated after radiation particles strike. The strike information is sensed by a sensor and then converted into data information by a front-end circuit and transmitted in parallel to a peripheral circuit for data transmission. Currently, in the field of radiation detection, the requirements for pixel resolution and detection rate are getting higher and higher, and the array scale is getting larger and larger. When the radiation particle strike frequency reaches a certain level, there will be a situation where both the data storage spaces of the front-end and peripheral circuits are full, but there is still new particle hit information that needs to be transmitted, resulting in a large amount of data loss. Generally speaking, due to the improvement of pixel resolution, the particle strike information shows a cluster characteristic during the transmission process, that is, when a radiation particle strikes, multiple adjacent pixel points will simultaneously sense the particle information, and these information belong to the same particle. Due to the difference in particle energy, the hit probability of the pixels around the cluster is relatively small. By virtue of this characteristic, a congestion mitigation architecture can be designed to alleviate the data congestion situation under high strike frequencies. Document 1 "Poikela, T.S.. "Readout Architecture for Hybrid Pixel Readout Chips." (2015). " contains a peripheral readout circuit. For readout, please refer to Figure 1 , a first-in-first-out memory is set for each channel. The data receiving module receives data from the column, synchronizes it and then stores it in the first-in-first-out memory, and transmits the data to other modules for subsequent encoding and other operations through two-level data selection. The two-level data selection adopts the same arbitration method. A memory is set inside each selector at each level, and the token ring method is adopted. When the memory is not full, a token ring permission to transmit is sent to the upper level. The token ring starts to search and stays at the first channel that needs to transmit data, reads the first-in-first-out memory empty and then looks for the next channel for data transmission.

[0003] The main disadvantages of the existing peripheral readout circuit are: when the pixel resolution is increased to a certain extent and the detection rate is increased to a certain frequency, with the expansion of the array scale, the data congestion situation during the transmission process becomes more and more serious. In addition, each channel having a dedicated memory will cause a large amount of storage space waste. For example, if several columns of pixels are struck multiple times within a period of time, while their adjacent pixels are always idle, this situation will not only cause data congestion, but also the overall storage space utilization rate of the peripheral circuit is relatively low. Summary of the Invention

[0004] An embodiment of the present invention provides a congestion mitigation data readout system, including:

[0005] A data receiving module that receives sensor array data of the corresponding channel when the first-in, first-out memory of the congestion mitigation module is not full;

[0006] A congestion mitigation module that is connected to two data receiving modules for every four groups of channels and selects to receive sensor array data within a group of synchronized channels in a rotating manner;

[0007] A continuous arbitration module that is connected to four congestion mitigation modules. When multiple congestion mitigation modules have data to be transmitted simultaneously, it selects one of the congestion mitigation modules in an arbitration manner to continuously transmit data until the first-in, first-out memory connected to the corresponding continuous arbitration module is empty;

[0008] A cyclic arbitration module that is connected to four continuous arbitration modules. When multiple continuous arbitration modules have data to be transmitted simultaneously, it reads one data from the first module in an arbitration manner and then sequentially reads one data from another continuous arbitration module until the data of all continuous arbitration modules is empty.

[0009] Furthermore, it also includes a sensor array data memory for temporarily storing the sensing information of multiple pixel points after radiation particles hit the sensor array. When it receives the enable information sent by the data receiving module and the enable information is valid, the sensor array data memory continuously transfers the sensor array data to the data receiving module.

[0010] Furthermore, the first-in, first-out memory is configured to determine whether the data is full. If it is not full, it sends a handshake signal to the data receiving module. When the handshake signal is valid, the data receiving module is allowed to receive the sensor array data, otherwise the channel data is temporarily stored in the sensor array data memory.

[0011] Furthermore, the congestion mitigation module includes two one-of-two data selectors and a first-in, first-out memory, where the depth of the first-in, first-out memory is determined according to the total sensor array data rate.

[0012] Furthermore, when the data receiving module receives the handshake signal and synchronizes the data to the first-in, first-out memory, it carries the row address and the response signal until the first-in, first-out memory is full or no data is read out from the sensor array.

[0013] Furthermore, when the handshake signal is valid, the enable information is valid.

[0014] Furthermore, the congestion mitigation module receives the enable signal of the continuous arbitration module as its data transmission flag. If the enable signal is valid and at the same time the empty signal sent by the first-in, first-out memory to the continuous arbitration module is not empty, it sends the buffered data to the continuous arbitration module.

[0015] Furthermore, the continuous arbitration module determines whether to transmit data according to the transmission enable sent by the cyclic arbitration module.

[0016] Furthermore, when the cyclic arbitration module reads the data of the non-empty continuous arbitration module, regardless of whether the continuous arbitration module has continuous data transmission, only one data is read, and then it immediately switches to the next continuous arbitration module.

[0017] The present invention also provides a congestion mitigation data reading method, which is characterized by including:

[0018] When the data receiving module is not full of the first-in-first-out memory of the congestion mitigation module, it receives the sensor array data of the corresponding channel;

[0019] The congestion mitigation module selects the sensor array data within a group of synchronized channels in a rotating manner;

[0020] When multiple congestion mitigation modules have data to be transmitted simultaneously, the continuous arbitration module selects one of the congestion mitigation modules in an arbitration manner to continuously transmit data until the first-in-first-out memory connected to the corresponding continuous arbitration module is empty;

[0021] When multiple continuous arbitration modules have data to be transmitted simultaneously, the cyclic arbitration module reads one data of the first module in an arbitration manner, and then sequentially reads one data of another continuous arbitration module until the data of all continuous arbitration modules is empty;

[0022] Among them, the congestion mitigation module is connected to two data receiving modules every four groups of channels, and the continuous arbitration module is connected to four congestion mitigation modules, and the continuous arbitration module is connected to four congestion mitigation modules.

[0023] The embodiments of the present invention provide a congestion mitigation data reading system and method. Compared with the prior art, the beneficial effects are as follows:

[0024] 1. Under the development trend of high resolution of the sensor array and high hit frequency of radiation particles, it can effectively alleviate the data congestion problem generated after the array data is transmitted in parallel to the peripheral readout circuit.

[0025] 2. Two channels with multiple columns in between share the same storage space. Under the same storage capacity, it can not only alleviate the local congestion situation where particles in a certain column are continuously hit while there are no other particles hit nearby, but also make more effective use of the storage space.

[0026] 3. Sharing the storage space reduces the number of subsequent arbitration module levels, can effectively reduce the chip area, save costs, and is more conducive to chip layout and wiring.

[0027] 4. When congestion is extremely severe, two arbitration mechanisms, continuous / cyclic, are adopted to reasonably obtain radiation particle information. The continuous arbitration tries to continuously transmit the same particle information to prevent information omission during processing. The cyclic arbitration gives each part of the sensor array the same output opportunity to prevent the continuous arbitration from only obtaining the particle information of a certain part of the array and losing all the information of the rest. The two restrict each other to balance the data congestion situation as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. Figure 1 is a schematic diagram of the peripheral readout circuit of the timepix3 chip in the background art;

[0029] FIG. Figure 2 is a schematic diagram of the overall architecture of congestion mitigation data readout for 64 sensor channels in the present invention;

[0030] FIG. Figure 3 is a schematic diagram of the connection of the data reception and congestion mitigation module in the present invention;

[0031] FIG. Figure 4 is a schematic diagram of the specific implementation of the congestion mitigation module in the present invention;

[0032] FIG. Figure 5 is a schematic diagram of the state transition of the congestion mitigation module in the present invention;

[0033] FIG. Figure 6 is a schematic diagram of the connection of the continuous and cyclic arbitration modules in the present invention;

[0034] FIG. Figure 7 is a schematic diagram of the state transition of the continuous arbitration module in the present invention;

[0035] FIG. Figure 8 is a schematic diagram of the state transition of the cyclic arbitration module in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] See Figures 1 to 8 , the embodiments of the present invention provide a congestion mitigation data readout system and method. The system includes: multiple groups of channels, each channel is grouped and cached according to the congestion situation, the data is transmitted in parallel, and after continuous and cyclic arbitration multiple times, it is output;

[0038] The data receiving module acquires the data transmitted through the corresponding channel, synchronizes it, and transmits the data with appended address information to the congestion mitigation module.

[0039] The congestion mitigation module connects two channels and includes a handshake protocol, channel selection, and a first-in-first-out memory. When a data conflict occurs, that is, when data is being transmitted on both channels simultaneously, it always alternately selects the data from one of the channels and passes it into the first-in-first-out memory. The depth of the first-in-first-out memory is determined according to the total data rate. When the memory is not full, it sends an allow-transmission signal to both channels. Each channel transmits data with an acknowledgment signal to the congestion mitigation module, which is the handshake protocol.

[0040] The continuous arbitration module connects four congestion mitigation modules, receives their empty signals, and selectively transmits their data. When multiple congestion mitigation modules have data to be transmitted simultaneously, it arbitrates and selects one of the modules for continuous transmission, that is, as long as the corresponding first-in-first-out memory of the selected congestion mitigation module is not empty, it keeps transmitting.

[0041] The cyclic arbitration module connects four continuous arbitration modules, receives their empty signals, and selectively transmits their data. When multiple continuous arbitration modules have data to be transmitted simultaneously, it arbitrates and transmits the data of each module cyclically. That is, after transmitting one data from the selected continuous arbitration module, it immediately switches to the next module for data transmission.

[0042] Furthermore, the two data receiving modules every four channels are connected to the same congestion mitigation module. The data receiving module sends a transmission enable to the sensor array according to the empty or full status of the memory in the congestion mitigation module.

[0043] Furthermore, when a data conflict occurs in the congestion mitigation module, it alternately reads the data from the corresponding two data receiving modules.

[0044] Furthermore, the two data receiving modules connected to the congestion mitigation module share the same first-in-first-out memory to cache data, and the overall storage capacity is determined according to the data rate set during sensor application.

[0045] Furthermore, the congestion mitigation module sends a handshake signal to the data receiving module according to whether the first-in-first-out memory is full. Only when the handshake signal is valid is the data receiving module allowed to receive the channel data; otherwise, the channel data is temporarily stored in the internal registers of each channel.

[0046] Furthermore, the continuous arbitration module connects four congestion mitigation modules and will select a certain congestion mitigation module to transmit data in the order of channels 1, 2, 3, and 4, and read the data from its first-in-first-out memory until the memory is empty.

[0047] Furthermore, the cyclic arbitration module mentioned above includes a multi-stage transmission structure, and each stage is similar. The formula for calculating the total number of stages is:

[0048]

[0049] Where N is the total number of stages of the cyclic arbiter, and K is the total number of sensor channels.

[0050] Furthermore, the cyclic arbitration module is characterized in that it is connected to four continuous arbitration modules. When selecting the data of a certain continuous arbitration module in the order of channels 1, 2, 3, and 4, regardless of whether there is continuous data transmission, only one data is received, and it immediately switches to the next module, giving each module the same data transmission opportunity.

[0051] A congestion mitigation data readout structure according to the present invention is characterized in that a congestion mitigation data readout structure is applied to the readout of sensor array information in fields such as radiation particle detection and medical imaging.

[0052] The congestion mitigation data readout structure according to the present invention includes the following steps:

[0053] Step 1: The sensor array generates data information and temporarily stores it in the internal register of the array.

[0054] Step 2: The data receiving module performs data transmission according to the full state of the connected first-in-first-out memory. If it is not full, it receives the data of the corresponding channel of the sensor array, and transmits the additional address and response information to the congestion mitigation module.

[0055] Step 3: The congestion mitigation module selects a certain data receiving module for data transmission. After checking the response information of the received data information, it stores it in the first-in-first-out memory.

[0056] Step 4: The continuous arbitration module selects a certain congestion mitigation module for data transmission according to the empty information of the corresponding first-in-first-out memory connected to the congestion arbitration module, and continuously receives its data until the corresponding first-in-first-out memory is empty.

[0057] Step 5: The first-level cyclic arbitration module selects a module for data transmission according to the empty information of the connected continuous arbitration module, and sequentially receives its data until the first-in-first-out memories connected to all continuous arbitration modules are empty.

[0058] Step 6: The remaining cyclic arbitration modules perform the same operation according to the empty information of the connected cyclic arbitration modules, and generate the final arbitration data for the next step of processing.

[0059] Embodiment:

[0060] The basic working principle of a congestion mitigation data readout structure according to the present invention:

[0061] Please refer to the appendix Figure 2 , the present invention designs a congestion mitigation data readout structure, Figure 2It is shown as a schematic diagram of a congestion mitigation readout architecture for a sensor array with 64 channels. According to the calculation formula of the cyclic arbitration module and rounding up, there are a total of 2 levels of cyclic arbitration modules. The overall architecture includes 64 data reception modules, 32 congestion mitigation modules, 8 continuous arbitration modules, and 3 cyclic arbitration modules in 2 levels.

[0062] After a radiation particle hits the sensor array, multiple pixel points sense information and temporarily store it in the internal memory of the array. When the data reception module sends a transfer enable signal, data transfer is allowed. When the transfer enable signal is valid, the sensor array continuously transmits data information to the data reception module.

[0063] After the data reception module receives the data, it first synchronizes it to prevent circuit timing errors caused by too long combinational paths. When the handshake signal is valid, the synchronized data is stored in the corresponding first-in-first-out memory together with the row address and the response signal until the first-in-first-out memory is full or there is no more data to be read out from the sensor array.

[0064] The congestion mitigation module sequentially transfers the buffered data from the memory to the continuous arbitration module in a first-in-first-out order. The continuous arbitration module continuously selects a certain congestion mitigation module it is connected to for transmission each time until the first-in-first-out memory is empty, that is, there is no more data to be transmitted on this channel within a certain time period. This time period is determined according to the radiation particle collision frequency in a specific application.

[0065] The cyclic arbitration module starts operating when the continuous arbitration module is not empty. Different from the continuous arbitration module, it gives each continuous arbitration module the same output opportunity.

[0066] Please refer to the appendix Figure 3 ., a transfer enable signal and a handshake signal are widely used in data transmission. The transfer enable from the data reception module to the sensor array is turned on and data transmission is allowed only when the handshake signal is valid, otherwise the data will remain in the sensor array all the time.

[0067] If the handshake signal is always invalid, a large amount of data will accumulate in the sensor array. When the next particle hits, congestion is likely to occur, and some data has to be discarded. The handshake signal is determined by the first-in-first-out memory of the congestion mitigation module. The handshake signal remains valid when the memory is not empty.

[0068] Please refer to the appendix Figure 4 ., the congestion mitigation module of the present invention consists of two multiplexers and a first-in-first-out memory. The two multiplexers are respectively responsible for the tasks of synchronously selecting data reception and configuring and sending handshake protocols, and they are interrelated. During the data reception process, the handshake signal is first sent according to the full signal of the first-in-first-out memory. The handshake signals connecting the two channels are both valid during initialization, so that at least one piece of data can reach the data reception module for data transmission.

[0069] Please refer to the attached Figure 5 , when the state transition diagram is in a certain channel, the handshake signal of that channel is valid. When the data selector senses the arrival of data, if there is only one channel with data requesting transmission, the handshake signal of that channel is kept valid and the handshake signal of the other channel is made invalid. If both channels have data to be transmitted, the handshake signal of a certain channel is alternately made valid and the handshake signal of the other channel is made invalid in the order of channel 1 -> 2 -> 1. Data is transmitted according to the handshake signal rule. Only when the handshake signal of one channel is valid and the other is invalid, the data of the channel with the valid handshake signal is selected and stored in the first-in-first-out memory.

[0070] During the data sending process, the congestion mitigation module receives the enable signal of the continuous arbitration module as its data transmission flag. When the enable signal is valid, data transmission is allowed. At this time, if the empty signal of the first-in-first-out memory is not empty, the buffered data is sent to the continuous arbitration module.

[0071] Please refer to the attached Figure 6 , the continuous arbitration module is essentially a four-to-one data selector, and decides whether to perform transmission according to the transmission enable sent by the cyclic arbitration module.

[0072] Please refer to the attached Figure 7 , where empty = 4’b1111 means that when there is no data transmission in each congestion mitigation module, it returns to the idle state. The arrow without indicating the jump condition means that the jump occurs under conditions other than the ones already indicated. When the empty signal of any module is 0, that is, in the non-empty state, if the transmission enable is valid, data transmission starts. The continuous arbitration module receives its data according to the empty signal of the congestion mitigation module. If it is non-empty, it receives the data; if it is empty, it skips this congestion mitigation module and judges the empty signal of the next module in the order of channel 1 -> 2 -> 3 -> 4 -> 1. If all are empty, it enters the idle state and stops searching. When reading the data of a certain congestion mitigation module, it will continue to read until its first-in-first-out memory is empty, that is, if the empty signal of the current module is 0, it will keep transmitting.

[0073] Please refer to the attached Figure 8 , the cyclic arbitration module is similar to the continuous arbitration module and is essentially also a four-to-one data selector. The only difference is that when reading the data of a certain non-empty continuous arbitration module, no matter whether there is continuous data transmission or not, only one data is read, and then immediately switches to the next module regardless of whether the next module has data to be transmitted.

[0074] The cyclic arbitration module enables the acquisition of information about different energy particles in the case of relatively serious congestion. The continuous arbitration module can transmit the energy information of a certain particle as completely as possible. The two restrict each other and balance the data congestion situation as much as possible.

[0075] The congestion mitigation data reading structure provided by the present invention can be applied to the reading of sensor array information in fields such as radiation particle detection and medical imaging.

[0076] The above are only several specific embodiments of the present invention. Those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. However, the embodiments of the present invention are not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A congestion mitigation data reading system, characterized in that Comprising: A data receiving module, which receives the sensor array data of the corresponding channel when the first-in first-out memory of the congestion mitigation module is not full; A congestion mitigation module, which is connected to two data receiving modules every four groups of channels, and selects to receive the sensor array data in a group of synchronized channels in a rotating manner; A continuous arbitration module, which is connected to four congestion mitigation modules. When multiple congestion mitigation modules have data to be transmitted simultaneously, it selects one of the congestion mitigation modules in an arbitration manner to continuously transmit data until the first-in first-out memory connected to the corresponding continuous arbitration module is empty; A cyclic arbitration module, which is connected to four continuous arbitration modules. When multiple continuous arbitration modules have data to be transmitted simultaneously, it reads one data from the first module in an arbitration manner, and then sequentially reads one data from another continuous arbitration module until the data of all continuous arbitration modules is empty.

2. The congestion mitigation data reading system according to claim 1, wherein It further includes a sensor array data memory, which is used to temporarily store the sensing information of multiple pixel points after radiation particles hit the sensor array. When it receives the enable information sent by the data receiving module and the enable information is valid, the sensor array data memory continuously transmits the sensor array data to the data receiving module.

3. The congestion mitigation data reading system according to claim 2, wherein The first-in first-out memory is configured to judge whether the data is full. If it is not full, it sends a handshake signal to the data receiving module. When the handshake signal is valid, the data receiving module is allowed to receive the sensor array data, otherwise the channel data is temporarily stored in the sensor array data memory.

4. The congestion mitigation data reading system according to claim 1, wherein The congestion mitigation module includes two one-out-of-two data selectors and a first-in first-out memory, wherein the depth of the first-in first-out memory is determined according to the total sensor array data rate.

5. The congestion mitigation data readout system according to claim 3, characterized in that, When the data receiving module receives the handshake signal and synchronizes the data to the first-in first-out memory, it carries the row address and the response signal until the first-in first-out memory is full or no data is read out from the sensor array.

6. The congestion mitigation data reading system according to claim 5, characterized in that, When the handshake signal is valid, the enable information is valid.

7. The congestion mitigation data readout system according to claim 1, characterized in that, The congestion mitigation module receives the enable signal of the continuous arbitration module as its data transmission flag. If the enable signal is valid and at the same time the empty signal sent by the first-in first-out memory to the continuous arbitration module is not empty, it sends the buffered data to the continuous arbitration module.

8. The congestion mitigation data readout system according to claim 1, wherein The continuous arbitration module decides whether to transmit data according to the transmission enable sent by the cyclic arbitration module.

9. The congestion mitigation data reading system according to claim 1, wherein When the cyclic arbitration module reads the data of the non-empty continuous arbitration module, no matter whether the continuous arbitration module continuously transmits data, it only reads one data and then immediately switches to the next continuous arbitration module.

10. A congestion mitigation data reading method, characterized in that, Comprising: The data receiving module receives the sensor array data of the corresponding channel when the first-in first-out memory of the congestion mitigation module is not full; The congestion mitigation module selects to receive the sensor array data in a group of synchronized channels in a rotating manner; The continuous arbitration module selects one of the congestion mitigation modules in an arbitration manner to continuously transmit data when multiple congestion mitigation modules have data to be transmitted simultaneously until the first-in first-out memory connected to the corresponding continuous arbitration module is empty; When there is data to be transmitted in multiple continuous arbitration modules simultaneously, the cyclic arbitration module reads one data of the first module in an arbitration manner and then sequentially reads one data of another continuous arbitration module until the data of all continuous arbitration modules is empty; Among them, the congestion mitigation module is connected to two data receiving modules every four groups of channels, and the continuous arbitration module is connected to four congestion mitigation modules, and the continuous arbitration module is connected to four congestion mitigation modules.

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