A kind of channel multiple devices and method based on RS frame structure
Technical field
The present invention relates to channel multiple devices and the method for polymorphic type business datum in a kind of digital microwave communication system.
Background technology
Digital microwave telecommunication is to utilize microwave band to carry out a kind of wireless transmission method of digital information transmission.Digital microwave communication system comprises indoor unit IDU and outdoor unit ODU.As shown in Figure 1, IDU is by several dissimilar business datum branch roads, comprise E1/T1/J1 branch road, Ethernet branch road, STM-1 branch road, path data-interface branch road GPI, talk-back branch road EOW and network management information branch road OMI carry out error correction coding and modulation treatment after by certain format multiple connection, then give ODU and send.Channel multiple connection is exactly to complete according to time division multiplexing principle the technology that code stream merges.Reed Solomon error correction coding, especially RS (204,188) form coding is widely used in microwave telecommunication system as a kind of error correction coding of maturation.Reed Solomon encodes taking frame as unit.RS (204,188) frame is identified by a byte RS frame head, and 187 byte net amounts according to this and 16 byte checking datas compositions.The business datum multiple connection method of existing IDU is first to define a kind of base band frame format, adopts the mode of poll that multi-channel service data multiplexing is arrived in base band frame, the then clean data division to RS frame by base band frame code stream subsection filling.There is following problem in this channel multiple connection mode: in the process of polymorphic type business datum branch road multiple connection, adopts polling mode to select business datum branch road, do not consider the sensitivity of different kinds of business data branch road to transmission delay.The clock jitter of time delay meeting aggravation E1/T1/J1 branch road, STM-1 branch road, path data-interface GPI tributary interface is waited in longer multiple connection, and in serious situation, clock jitter can exceed the disposal ability of business datum interface equipment and produce error code; Existing channel multiple connection method is inserted base band frame identification in channel, and the base band frame identification of insertion need to take radio channel resource; Meanwhile, twice framing of base band frame and RS frame increased circuit complexity.
Summary of the invention
The present invention is for avoiding the existing weak point of above-mentioned prior art, a kind of channel multiple devices based on RS frame structure is provided, solve the problem that polymorphic type business datum is multiplexed into digital microwave physical channel, and reduce the complexity of channel multiple devices, avoid base band frame identification information busy channel resource, improve channel utilization.
The present invention is achieved through the following technical solutions.
The present invention is based on the channel multiple devices of RS frame structure, be by dissimilar some business datum branch road data multiplexings to digital microwave physical channel, described business datum branch road comprises: some E1/T1/J1 branch roads, some STM-1 branch roads, Ethernet branch road, universal data interface branch road GPI, talk-back branch road EOW and network management information branch road OMI; Described digital microwave physical channel props up circuit-switched data for service data transmission; It is characterized in that described channel multiple devices comprises:
One business datum interface monitor circuit, for monitoring data bulk and the empty full state of business datum interface buffer area;
One business datum buffer area, for the data of each business datum branch road of buffer memory;
One multiple connection control circuit, for selecting multiple connection data from some business datum branch roads; Described multiple connection control circuit is a business datum multiple connection counter of every business datum branch road configuration, with the continuous not number of times of selected multiple connection of described business datum multiple connection counter records corresponding service data branch road;
One RS frame generative circuit, for generate RS frame and multiple connection Data Identification information and by multiple connection data stuffing to RS frame;
One CPU element, enables table for the multiple connection of business datum branch road is set.
The feature that the present invention is based on the channel multiple connection method of the channel multiple devices of RS frame structure is to carry out according to the following steps:
A, some business datum branch roads are divided into the business datum branch road that allows to be multiplexed into the business datum branch road of channel and forbid being multiplexed into channel; In channel multiple connection control circuit, comprise a multiple connection and enable table, described multiple connection enables business datum branch road of each correspondence in table, to indicate corresponding business datum branch road whether to allow to be multiplexed into channel; Described multiple connection enables table and sets in advance according to application demand, or by CPU online modification;
B, with business datum interface monitor circuit query traffic data Interface status, by the status information feedback of business datum interface to channel multiple connection control circuit;
C, channel multiple connection control circuit enable to show content according to the priority of business datum Interface status, business datum branch road and multiple connection and carry out multiple connection selection, and a business datum branch road is selected in each multiple connection; First described channel multiple connection control circuit is selected from high-priority service data branch road, if do not chosen, then selects in low priority traffice data branch road; If all do not chosen, explanation needs multiple connection without business datum temporarily; Selection result is passed to RS frame generative circuit by channel multiple connection control circuit;
D, generate RS frame and multiple connection Data Identification information with RS frame generative circuit, then by Data Identification information and be filled into the clean data division of RS frame for the business datum of multiple connection, complete a multiple connection; Repeating step B, C and D, realize the channel multiple connection based on RS frame.
The feature of channel multiple connection method of the present invention is also:
In described step C, the priority of business datum branch road refers to that described business datum branch road is divided into high-priority service data branch road and low priority traffice data branch road; Described high-priority service data branch road refers to multiple connection to wait for the strict business datum branch road of delay requirement, comprises E1/T1/J1, STM-1 and GPI business datum branch road; Described low priority traffice data branch road refers to multiple connection to wait for the business datum branch road of delay requirement lower than high-priority service data branch road; Described low priority traffice data branch road comprises Ethernet branch road, talk-back branch road and network management information branch road.
The multiple connection of channel described in step C control circuit is selected from high-priority service data branch road: select successively a business datum branch road of the high-priority service data branch road that allows multiple connection, relatively whether this business datum branch road is greater than business datum multiple connection quantity thresholding at the data bulk of business datum buffer area buffer memory; If be greater than, select this business datum branch road to carry out multiple connection, the data bulk of multiple connection is 186 bytes, multiple connection has been selected; Otherwise, judge as stated above whether next high-priority service data branch road meets multiple connection requirement; If high-priority service data branch road does not meet multiple connection requirement, forward low priority traffice data branch road to and carry out multiple connection selection.
Described in step C, channel multiple connection control circuit selects the method that is used for multiple connection business datum branch road to be from low priority traffice data branch road:
A, from allow the low priority traffice data branch road of multiple connection, select a business datum branch road, relatively whether this business datum branch road is greater than business datum multiple connection quantity thresholding at the data bulk of business datum buffer area buffer memory, if be greater than, select this business datum branch road to carry out multiple connection, the data bulk of multiple connection is 185 bytes, and multiple connection has been selected; Otherwise, proceed to step b;
B, judge whether this business datum branch road multiple connection counter is greater than 3, if be greater than 3, select this business datum branch road to carry out channel multiple connection, this business datum branch road multiple connection counter O reset, the quantity of multiple connection data is the data bulk of current business data buffer area buffer memory; Otherwise this business datum branch road multiple connection counter adds 1, proceeds to step a.
Multiple connection Data Identification information described in step D is made up of two bytes; The first byte is business datum branch road ID, and span is 0-63, respectively corresponding 63 the business datum branch roads of its intermediate value 1-63, and value 0 indicates to need multiple connection without business datum; In the time that multiple connection data are high-priority service data, the second byte is used to service data transmission; In the time that multiple connection data are lower-priority data, the length of the multiple connection data of filling in the second byte representation RS frame, span is 1-185.
Business datum described in step D is filled into the clean data division of RS frame and also comprises: when the data of multiple connection are low priority traffice data and data bulk while being less than 185 byte, mend 0 in multiple connection data trailer, be filled into the clean data division of RS frame after polishing 185 bytes.
Compared with the prior art, beneficial effect of the present invention is embodied in
1, the invention solves polymorphic type business datum and be multiplexed into the problem of digital microwave physical channel.Because the multiple connection of business datum branch road selects to adopt the method for dividing based on priority, reduced E1/T1/J1 branch road, STM-1 branch road, thereby the path data-interface GPI branch road wait multiple connection time reaches the object of optimizing business datum tributary interface clock jitter performance.
2, in the present invention, channel multiple devices only needs the framing of a RS frame, thereby reduces the complexity of channel multiple devices, avoids base band frame identification information busy channel resource, improves channel utilization.
Brief description of the drawings
Fig. 1 is the key diagram for IDU signal processing module;
Fig. 2 is the key diagram of RS (204,188) frame structure;
Fig. 3 is the key diagram of multiple connection Data Identification information;
Fig. 4 is channel multiple devices structural representation of the present invention;
Fig. 5 is channel multiple connection method flow diagram of the present invention.
Embodiment
As shown in Figure 4, the channel multiple devices based on RS frame in the present embodiment comprises: business datum interface monitor circuit 401, and business datum buffer area 402, multiple connection control circuit 403, RS frame generative circuit 404, CPU element 405 and MUX 406, wherein:
Business datum interface monitor circuit 401 is for monitoring data bulk and the empty full state of business datum interface buffer area;
Business datum buffer area 402 is for the data of each business datum branch road of buffer memory;
Multiple connection control circuit 403 is for selecting multiple connection data from some business datum branch roads; Multiple connection control circuit is a business datum multiple connection counter of every business datum branch road configuration, with the continuous not number of times of selected multiple connection of described business datum multiple connection counter records corresponding service data branch road;
RS frame generative circuit 404 for generate RS frame and multiple connection Data Identification information and by multiple connection data stuffing to RS frame;
CPU element 405 enables table for the multiple connection of business datum branch road is set.
Referring to Fig. 5, the multiple connection method in the present embodiment is carried out according to the following steps:
Step 501, after system power-up, user arranges multiple connection by CPU element 405 and enables table, selects to allow to be multiplexed into the business datum branch road of channel according to user's request.Be further: CPU element 405 is calculated the required channel width summation of branch road that user selects that, in the time that branch road bandwidth demand is greater than the channel width that system can provide, for avoiding loss of data, prompting user reselects the business datum branch road of permission multiple connection.
After arranging successfully, multiple connection control circuit 403 reads in multiple connection and enables table.User can change at any time multiple connection by CPU element 405 and enable table, and the multiple connection multiple connection of reading in that enables after table amendment can notice multiple connection control circuit 403 to upgrade in time enables table.
Step 502, business datum interface monitor circuit 401 is inquired about each business datum and is propped up the state of circuit-switched data in business datum buffer area 402.First the data of each business datum branch road are buffered in business datum buffer area 402 after entering IDU.Business datum interface monitor circuit 401 by the status information feedback inquiring to multiple connection control circuit 403.
Step 503, multiple connection control circuit 403 selects a business datum branch road in many business datum branch roads to carry out this multiple connection.Be further that first multiple connection control circuit 403 is selected in the following manner from high-priority service data branch road:
Relatively allow successively a business datum branch road in the high-priority service data branch road of multiple connection whether to be greater than business datum multiple connection quantity thresholding at the data bulk of business datum buffer area buffer memory; If be greater than, select this business datum branch road to carry out multiple connection, the data bulk of multiple connection is 186 bytes, multiple connection has been selected; Otherwise, judge as stated above whether next high-priority service data branch road meets multiple connection requirement.If the business datum branch road of high priority does not meet multiple connection requirement, forward low priority traffice data branch road to and carry out multiple connection selection.
Channel multiple connection control circuit is selected according to the following steps for multiple connection business datum branch road from low priority traffice data branch road:
A, from allow the low priority traffice data branch road of multiple connection, select one, relatively whether this business datum branch road is greater than business datum multiple connection quantity thresholding at the data bulk of business datum buffer area buffer memory, if be greater than, select this business datum branch road to carry out multiple connection, the data bulk of multiple connection is 185 bytes, and multiple connection has been selected; Otherwise, proceed to step b;
B, judge whether the multiple connection counter of this business datum branch road is greater than 3.If be greater than 3, select this business datum branch road to carry out channel multiple connection, counter O reset, the quantity of multiple connection data is the data bulk of current business data buffer area buffer memory; Otherwise, again proceed to step a after the multiple connection counter of business datum branch road is added to 1.
If all do not chosen, explanation needs multiple connection without business datum temporarily.Selection result is passed to RS frame generative circuit 404 by channel multiple connection control circuit 403.
Step 504, RS frame generative circuit 404 generates RS (204,188) frame.The structure of RS (204,188) frame as shown in Figure 2, is first the frame head mark of a byte, is worth for " 47H " or step-by-step inverted value " B8H ".The assignment principle of frame head mark is that continuous 7 frames are with closelying follow a use " B8H " mark, according to this circulation after " 47H ".RS frame generative circuit 404 generates multiple connection Data Identification information according to the selection result of channel multiple connection control circuit 403 simultaneously.As shown in Figure 3, Data Identification information totally 2 bytes.The first byte is business datum branch road ID, and span is 0-63, respectively corresponding 63 the business datum branch roads of its intermediate value 1-63, and value 0 indicates to need multiple connection without business datum.In the time that multiple connection data are high-priority service data, the second byte is used to service data transmission; In the time that multiple connection data are lower-priority data, the length of the multiple connection data of filling in the second byte representation RS frame, span is 1-185.
RS frame generative circuit 404 is inserted multiple connection data message mark, multiple connection data at the clean data segment of RS frame.Finally 16 byte RS frame check position placeholders.Complete thus the once multiple connection based on RS frame.After RS coding, this 16 byte placeholder is replaced with to corresponding check code.
Repeating step 502 to 504, realizes the channel multiple connection based on RS frame.