CN102684815A - Transmission method and transmission system for cooperative communication and relay node - Google Patents

Abstract

The invention discloses a transmission method and a transmission system for cooperative communication and a relay node, and relates to the technical field of communication. The transmission method, the transmission system and the relay node solve the problem of poor decoding performance of a cooperative communication system in the prior art. The transmission method in an embodiment includes: enabling signals transmitted by a receiving source node in a current time slot and other relay node forwarding signals to form aliasing signals, wherein the other relay node forwarding signals include signals transmitted by the source node in at least previous time slot; decoding the aliasing signals to obtain the signals transmitted by the source node in the current time slot and the at least previous time slot; performing superposition coding for the signals transmitted by the source node in the current time slot and the at least previous time slot; and forwarding the signals subjected to superposition coding in a following time slot. The transmission method, the transmission system and the relay node in the embodiment are mainly used for a cooperative communication system.

Description

The transmission method of collaboration communication, via node and transmission system

Technical field

The present invention relates to communication technical field, relate in particular to transmission method, via node and the transmission system of collaboration communication.

Background technology

Collaboration communication (Cooperative communication) technology is the technology that development in recent years is got up; Typical case's cooperation communication system comprises three kinds of nodes: source node; Via node and destination node; Wherein as the source node of information source and as communicating between the destination node of the stay of two nights, the via node in the cooperation communication system can receive the signal that source node sends, and be transmitted to destination node; And the signal that destination node generally can either the reception sources node be sent also can receive the signal that via node is transmitted; Certainly, in the partial cooperative communication system, destination node also can receive only the signal that via node is transmitted.

Because the via node of cooperation communication system can use the travelling carriage that has an antenna; Make the antenna that to share other mobile subscribers in multi-user environment when the user communicates; Can produce many virtual transmitting antennas like this; And then obtain corresponding diversity gain, improve the performance of GSM.

For the effectiveness and the availability of frequency spectrum in the cooperation communication system are provided; Collaboration communication of the prior art is two via nodes of general employing between source node and destination node; Take turns reception sources node data bag and forward relay signal through two via nodes, so that destination node can receive new data message continuously at each time slot.The trunking method that continues of utilizing two via nodes to take turns to operate has improved the efficiency of transmission of system; But via node receives the interference that another sends relaying at the Bao Shihui of reception sources transmission; This technology has adopted interference elimination method respectively source node and the signal that another via node sends to be decoded, and carries out repeated encoding and then transmission at the next time slot source node that obtains of will decode at the signal of current time slots transmission.

State in realization in the process of cooperation communication system; The inventor finds to exist at least in the prior art following problem: the one, and only will decode signal that the source node that obtains sends in current time slots of via node carries out repeated encoding and sends; The signal that another via node that does not utilize decoding to obtain sends; Can not make full use of coding gain, systematic function haves much room for improvement; The 2nd, when source node was close to the channel quality between the channel quality of via node and two via nodes, the decoding performance of existing cooperation communication system was relatively poor.

Summary of the invention

Embodiments of the invention provide a kind of transmission method, via node and transmission system of collaboration communication, improve the decoding performance of cooperation communication system.

For achieving the above object, embodiments of the invention adopt following technical scheme:

A kind of transmission method of collaboration communication comprises:

The reception sources node is at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot;

Decoding obtains the signal that signal that said source node sends in current time slots and source node send at last at least time slot from said aliasing signal;

Said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, obtain the signal behind the supercomposed coding;

Signal behind the said supercomposed coding is transmitted at next time slot.

A kind of via node comprises:

Receiving element is used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot;

Decoding unit is used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal;

Coding unit is used for said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, and obtains the signal behind the supercomposed coding;

Retransmission unit is used for the signal behind the said supercomposed coding is transmitted at next time slot.

A kind of transmission system of collaboration communication comprises:

Source node is used for sending signal in current time slots;

At least two via nodes are used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot; Also be used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal; Said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, obtain the signal behind the supercomposed coding; Signal behind the said supercomposed coding is transmitted at next time slot;

Destination node is used to receive the signal behind the supercomposed coding that via node transmits, and decodes to the received signal and obtain the signal that source node sends.

A kind of transmission method of collaboration communication comprises:

The aliasing signal that the network code signal that the reception sources node is transmitted at signal and other via nodes of current time slots transmission at current time slots transmission signal reception sources node is formed, the network code signal of said other via nodes forwardings comprises the signal of source node in last at least time slot transmission;

Said aliasing signal is mapped to the network code signal of the signal of source node transmission;

Separate decoding information from said the mapping the network code signal that;

Separate the network code signal of decoding information in next time slot forwarding.

A kind of via node comprises:

Receiving element; Be used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via nodes transmit is formed, the network code signal that said other via nodes are transmitted comprises the signal that source node sends at last at least time slot;

Map unit is used for said aliasing signal is mapped to the network code signal that source node sends signal;

Separative element is used for separating decoding information from the said network code signal that shines upon;

Retransmission unit is used for separating the network code signal of decoding information in next time slot forwarding.

A kind of transmission system of collaboration communication comprises:

Source node is used for sending signal in current time slots;

At least two via nodes; Be used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via node transmit is formed, the network code signal that said other via node is transmitted comprises the signal that source node sends at last at least time slot; Also be used for said aliasing signal is mapped to the network code signal that source node sends signal, separate decoding information, and transmit at next time slot and to separate the network code signal of decoding information from said the mapping the network code signal that;

Destination node is used to receive the network code signal that via node is transmitted, and the network code signal that receives decoded obtains the signal that source node sends.

A kind of transmission method of collaboration communication comprises:

Obtain first channel quality and the second channel quality between the via node between equivalent channel quality, source node and the via node between source node and the destination node;

Calculate the bad channel quality between said first channel quality and the said second channel quality;

In said equivalent channel quality during, carry out collaboration communication according to the transmission method of collaboration communication described in claim 1 or 2 less than first predetermined threshold;

When said equivalent channel quality is not less than first predetermined threshold, judge that whether said bad channel quality is greater than second predetermined threshold;

In said bad channel quality during, carry out collaboration communication according to the transmission method of collaboration communication described in claim 1 or 2 greater than second predetermined threshold;

When said bad channel quality is not more than second predetermined threshold, carry out collaboration communication according to the transmission method of the said collaboration communication of claim 8.

The transmission method of the collaboration communication that the embodiment of the invention provides, via node and transmission system; The transmission method of collaboration communication need receive the signal of source node and other via nodes simultaneously in the embodiment of the invention in current time slots; Then the signal that receives is decoded and recompile or mapping and separation, and the mapping signal after recompile signal or the separation is transmitted.

Then be all to decode out when decoding with receiving the signal that all source nodes send in the signal; So that can source node be carried out supercomposed coding and forwarding at the signal of the transmission of two time slots at next time slot; When adopting this transmission plan, can improve decoding performance in the cooperation communication system.

When shining upon; Need aliasing signal be mapped to the network code signal that source node sends signal; That is to say in the aliasing signal signal terms of the signal correction that any one and source node send, all need be mapped in the network code signal, and separate decoding information and transmit then; When adopting this transmission plan, can improve decoding performance in the cooperation communication system.

Description of drawings

In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art; To do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below; Obviously, the accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills; Under the prerequisite of not paying creative work property, can also obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the transmission plan sketch map of four node radio communications in the prior art;

Fig. 2 is the time slot map of collaboration communication in the prior art;

Fig. 3 is the transmission method flow chart of a kind of collaboration communication in the embodiment of the invention 1;

Fig. 4 is the block diagram of a kind of via node in the embodiment of the invention 1;

Fig. 5 is the schematic diagram of a kind of cooperation communication system in the embodiment of the invention 1;

Fig. 6 is the transmission method flow chart of another kind of collaboration communication in the embodiment of the invention 1;

Fig. 7 is the block diagram of another kind of via node in the embodiment of the invention 1;

Fig. 8 is the schematic diagram of another kind of cooperation communication system in the embodiment of the invention 1;

Fig. 9 is the transmission method flow chart of another collaboration communication in the embodiment of the invention 1;

Figure 10 is the transmission method flow chart of a kind of collaboration communication in the embodiment of the invention 2;

Figure 11 is the time slot map of collaboration communication in the embodiment of the invention 2;

Figure 12 is the process flowchart of relaying in the embodiment of the invention 2;

Figure 13 is the block diagram of via node in the embodiment of the invention 2;

Figure 14 is the schematic diagram of cooperation communication system in the embodiment of the invention 2;

Figure 15 is the transmission method flow chart of collaboration communication in the embodiment of the invention 3;

Figure 16 is the time slot map of collaboration communication in the embodiment of the invention 3;

Figure 17 is the process flowchart of relaying in the embodiment of the invention 3;

Figure 18 is the block diagram of via node in the embodiment of the invention 3;

Figure 19 is the schematic diagram of cooperation communication system in the embodiment of the invention 3;

Figure 20 is the transmission method flow chart of collaboration communication in the embodiment of the invention 4;

Figure 21 is the illustraton of model of analogue system in the embodiment of the invention;

Figure 22 is simulated effect figure when channel quality is better between the relaying in the embodiment of the invention;

Figure 23 is simulated effect figure when channel quality is relatively poor between the relaying in the embodiment of the invention;

Figure 24 is 25dB for receiving SNR in the embodiment of the invention, the simulated effect figure when repeater span is nearer.

Embodiment

Shown in Figure 1 is the sketch map of the transmission plan of four node radio communications, and the trunking method that continues that this transmission plan utilizes two via nodes to take turns to operate has improved the efficiency of transmission of system.Via node receives the interference that another sends relaying at the Bao Shihui of reception sources transmission; This technology has adopted interference elimination method; The reception signal that channel quality is relatively poor is regarded the approximation method extraction source signal of Gaussian noise as, and at next time slot the source signal that decoding obtains is carried out repeated encoding and then transmission.This technology has proposed when relaying disturbs by force, can consider decoding interference signal (signal that another via node sends) earlier, obtains desired signal (source signal) again.At destination, after receiving the transmission signals of a plurality of time slots, the method for V-BLAST (Vertical Bell Labs Layered Space-Time is during vertical bell laboratories layered space) detects when utilizing sky.

In Fig. 1, in first time slot, source node S is sent signal S1, and via node R1 carries out the reception of signal, so, the S1 that via node R1 reception sources node sends in first time slot; In second time slot; Source node S is sent signal S2; Another via node S2 carries out the reception of signal, and via node R1 is sent in the signal S1 that first time slot receives simultaneously, so; Via node R2 can receive S1 and S2 in second time slot, and destination node D then receives the S1 that via node R1 sends; In the 3rd time slot; Source node S is sent signal S3; Via node R1 carries out signal and receives, and via node R2 is sent in the signal S2 that second time slot obtains through the interference eliminated decoding, so; Via node R1 can receive S2 and S3 in the 3rd time slot, and destination node D then receives the S2 that via node R2 sends.

Certainly, if having transmission link between source node S and the destination node D, the signal of destination node D reception sources node transmission simultaneously.The time slot map of the transmission plan of radio communication is as shown in Figure 2 among Fig. 1.

The embodiment of the invention provides a kind of transmission method, via node and transmission system of collaboration communication.To combine the accompanying drawing in the embodiment of the invention below, the technical scheme in the embodiment of the invention is carried out clear, intactly description, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills are not making the every other embodiment that is obtained under the creative work prerequisite, all belong to the scope of the present invention's protection.

Embodiment 1:

The embodiment of the invention provides a kind of transmission method of collaboration communication, and is as shown in Figure 3, and said transmission method comprises:

301, the reception sources node is at the signal of current time slots transmission and the aliasing signal of other via node forward signals composition, and said other via node forward signals comprise the signal that source node sends at last at least time slot.

302, decoding obtains the signal that signal that said source node sends in current time slots and source node send at last at least time slot from said aliasing signal.

303, said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, obtain the signal behind the supercomposed coding.

304, the signal behind the supercomposed coding is transmitted at next time slot.

The embodiment of the invention also provides a kind of via node, and is as shown in Figure 4, and said via node comprises: receiving element 41, decoding unit 42, coding unit 43, retransmission unit 44.

Wherein, receiving element 41 is used for the aliasing signal that the reception sources node is formed at the signal and the via node forward signal of current time slots transmission, and said via node forward signal comprises the signal that source node sends at last at least time slot; Decoding unit 42 is used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal; Coding unit 43 is used for said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, and obtains the signal behind the supercomposed coding; Retransmission unit 44 is used for the signal behind the supercomposed coding is transmitted at next time slot.

The embodiment of the invention also provides a kind of transmission system of collaboration communication, and is as shown in Figure 5, and said system comprises: source node 51, at least two via nodes 52 and destination nodes 53.

Wherein, source node 51 is used for sending signal in current time slots; At least two via nodes 52 are used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot; Also be used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal; Said source node is carried out supercomposed coding at the signal of current time slots and the transmission of last time slot, and the signal behind the supercomposed coding is transmitted at next time slot; Destination node 53 is used to receive the signal behind the supercomposed coding that via node transmits, and decodes to the received signal and obtain the signal that source node sends.

The embodiment of the invention also provides a kind of transmission method of collaboration communication, mainly adopts the mode of the network code relay transmission that continues in the present embodiment, and as shown in Figure 6, said method comprises:

601, the aliasing signal formed of the network code signal transmitted of the signal that sends in current time slots of reception sources node and other via nodes, the network code signal that said other via nodes are transmitted comprises the signal that source node sends at last at least time slot.

602, said aliasing signal is mapped to the network code signal that source node sends signal.

603, separate decoding information from said the mapping the network code signal that.

604, separate the network code signal of decoding information in next time slot forwarding.

The embodiment of the invention also provides a kind of via node, and is as shown in Figure 7, and said via node comprises: receiving element 71, map unit 72, separative element 73, retransmission unit 74.

Wherein, receiving element 71 is used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and via node transmit is formed, and the network code signal that said via node is transmitted comprises the signal of source node in last at least time slot transmission; Map unit 72 is used for said aliasing signal is mapped to the network code signal that source node sends signal; Separative element 73 is used for separating decoding information from the said network code signal that shines upon, and retransmission unit 74 is used for separating the network code signal of decoding information in next time slot forwarding.

The embodiment of the invention also provides a kind of transmission system of collaboration communication; As shown in Figure 8; Said system comprises: source node 81, via node 82 and destination node 83; Generally at least two of via nodes in the present embodiment are that example describes with two via nodes among Fig. 8, but not as the qualification of protection range of the present invention.

Wherein, source node 81 is used for sending signal in current time slots;

At least two via nodes 82 are used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via node transmit is formed, and the network code signal that said other via node is transmitted comprises the signal that source node sends at last at least time slot; Via node 82 also is used for said aliasing signal is mapped to the network code signal that source node sends signal, separates decoding information from said the mapping the network code signal that, and transmits at next time slot and to separate the network code signal of decoding information; Destination node 83 is used to receive the network code signal that via node 82 is transmitted, and the network code signal that receives decoded obtains the signal that source node sends.

The embodiment of the invention also provides a kind of transmission method of collaboration communication, and is as shown in Figure 9, and said method comprises:

901, before the system transmissions process begins, obtain first channel quality and the second channel quality between the via node between equivalent channel quality eSNR, source node S and the via node R between source node S and the destination node D.

During concrete the realization, the concrete scheme of this process is: before the system transmissions process began, source node and via node took different time-gap respectively and send training sequence.Through training sequence, via node can obtain own and source node and and another via node between channel quality information, be equivalent to obtain channel quality and the channel quality between the via node between source node and the via node.Simultaneously destination node also can obtain and source node and and via node between channel quality information; And give via node with the channel quality information feedback that obtains by destination node, via node can obtain the equivalent channel quality eSNR between source node and the destination node.Wherein equivalent channel quality eSNR is defined as: establishing receiving matrix is H, the nonzero element h among the H _IjExplained that receiving terminal has received effective source information S at i time slot _jSignal component, the equivalent SNR that receives this part signal is h _IjSNR.If the nonzero element set is C among the H _H, then the equivalent SNR of system can be expressed as:

902, the bad channel quality between said first channel quality of calculating and the second channel quality; Channel quality between source node S and the via node R is used SNR _SRExpression, channel quality is used SNR between the via node _RRExpression, concrete bad channel quality Δ SNR=SNR _RR-SNR _SR

903, whether judge said equivalent channel quality eSNR less than first predetermined threshold, if eSNR less than first predetermined threshold, then carries out 905; If eSNR is not less than first predetermined threshold, then carry out 904.

904, judge that whether said bad channel quality Δ SNR is greater than second predetermined threshold; If Δ SNR greater than second predetermined threshold, then carries out 905; If Δ SNR is not more than second predetermined threshold, then carry out 906.

905, carry out collaboration communication according to the transmission method that collaboration communication is provided in the scheme shown in Figure 3.

906, carry out collaboration communication according to the transmission method that collaboration communication is provided in the scheme shown in Figure 6.

The transmission method of the collaboration communication that the embodiment of the invention provides, via node and transmission system; The transmission method of collaboration communication need receive the signal of source node and other via nodes simultaneously in the embodiment of the invention in current time slots; Then the signal that receives is decoded and recompile or mapping and separation, and the mapping signal after recompile signal or the separation is transmitted.

Then be all to decode out when decoding with receiving the signal that all source nodes send in the signal; So that can source node be carried out supercomposed coding and forwarding at the signal of the transmission of two time slots at next time slot; When adopting this transmission plan, can improve decoding performance in the cooperation communication system.

When shining upon; Need aliasing signal be mapped to the network code signal that source node sends signal; That is to say in the aliasing signal that any one and source node send the signal terms of signal correction, all need be mapped in the network code signal, and separate decoding information and transmit then; When adopting this transmission plan, can improve decoding performance in the cooperation communication system.

Embodiment 2:

The embodiment of the invention provides a kind of transmission method of collaboration communication, and the scheme with supercomposed coding is that example describes in the present embodiment, but supercomposed coding can not be as the qualification of protection range of the present invention.

The application scenarios of supposing the embodiment of the invention is: in wireless relay system, have a source node, and communicate through assistance and destination node of two via nodes.Source node, two via nodes and purpose stage all are operated under the semiduplex mode, that is to say that each node can not receive and dispatch simultaneously.The data that the hypothesis source node need transmit in transmission course can be divided into L packet.In embodiments of the present invention, through the assistance of two relayings, system need distribute L+2 this L of slot transmission packet.At source node, packet is sent out at a continuous L time slot; Two via nodes take turns to operate under transmission and listening state, and each time slot has only a via node to transmit the packet of source node.

Source node is contact to send packet at first time slot to L time slot, but two via nodes are to intercept the also packet of reception sources node transmission at first time slot.In second time slot; One of them via node R1 will send after first time slot receives decoded packet data; This moment, destination node can both receive the packet that this via node R1 sends with another via node R2; And R2 can also receive the packet that source node sends in second time slot; Be equivalent to R2 and receive the aliasing plus signal from R1 and source node signal, this situation can be regarded two users' access channel state as, can decode the signal from different nodes through the method for serial interference elimination (SIC) (seeing flow chart).

And at the 3rd follow-up time slot in L time slot; Two via nodes all need the packet of reception sources node transmission simultaneously and another via node to transmit data, that is: via node is receiving and decoding by the aliasing signal of forward relay and source node transmission.

It is shown in figure 10 that via node receives the transmission method of aliasing signal, and said method comprises:

1001, the reception sources node is at the signal of current time slots transmission and the aliasing signal of other via node forward signals composition; Said other via node forward signals comprise the signal that source node sends at last at least time slot, and the signal that said via node is transmitted is through the signal behind the supercomposed coding.The supercomposed coding of the embodiment of the invention specifically can adopt but be not limited to the supercomposed coding of energy normalized.

1002, cancellation had before been decoded and had been obtained the signal that source node sends from said aliasing signal.

1003, the signal that source node is sent in current time slots is as noise, obtains the signal that said source node sends at last time slot through interference elimination method decoding from the aliasing signal of the previous decoded signal of cancellation.

1004, the signal that the said source node of cancellation sends at last time slot from the aliasing signal of the previous decoded signal of cancellation obtains the signal that said source node sends in current time slots.

Accomplished following function through above-mentioned steps 1002 to 1004: decoding obtains the signal that signal that said source node sends in current time slots and source node send at last at least time slot from said aliasing signal.

1005, with said source node at signal that current time slots and last time slot send through behind the supercomposed coding of energy normalized, transmit through the signal behind the supercomposed coding at next time slot.

Carry out the description of branch time slot in the face of above-mentioned application scenarios down, shown in figure 11, the concrete host-host protocol from time slot 1 to time slot L+1 is following:

Time slot 1: via node R1 and via node R2 monitor the packet that source node S is sent.

Time slot 2: at previous time slot, R1 has only received the signal from source node, after decoding, only needs the corresponding repetition-coded data bag of transmission.R2 receives the aliasing plus signal from R1 and source node signal in this time slot, this situation can be regarded two users' access channel state as, can decode the signal from different nodes through the method for serial interference elimination (SIC) (seeing flow chart).

Time slot 3 to time slot L: via node R1 and R2 are all receiving and are decoding by the aliasing signal that another via node is transmitted and source node transmits in each time slot; The last time slot SDI that source node data and another via node are sent carries out behind the supercomposed coding of energy normalized in next time slot forwarding, and destination node then receives the signal of above-mentioned forwarding.In embodiments of the present invention, via node has adopted the way of energy normalized when signal is done supercomposed coding, promptly the power normalization of the supercomposed coding signal of transmitting; In real system, via node also can not adopt the way of energy normalized when signal is done supercomposed coding.Present embodiment adopts the purpose of energy normalized way to be to carry out performance comparison with prior art more intuitively.

Time slot L+1; Source node no longer transmits new packet, and trunk monitoring is only received the signal from another relaying.It can obtain new information according to the supercomposed coding signal component of having decoded, and gives destination node in the L+2 slot transmission.

Is example with via node R2 among Figure 11 the 4th time slot reception condition, and the processing procedure of R2 is shown in figure 12, specifically comprises:

1201, in the 4th time slot; Via node R2 receives the signal of R1 transmission and the mixed signal that falls of the signal that source node sends; Because the signal that R1 sends is the signal behind the supercomposed coding of energy normalized, as shown in Figure 11, the signal that R1 sends in the 4th time slot can be expressed as:

So the signal that R2 specifically receives can be expressed as:

S wherein ₂Be the signal that source node sends at the 2nd time slot, S ₃Be the signal that source node sends at the 3rd time slot, S ₄Be the signal of source node the 4th time slot transmission; h _R1r2Be two weak parameters of the channel between the via node,, h _Sr2Be the weak parameter of channel in the middle of source node and the via node R2.

1202, because via node R2 is decoding S before ₂So R2 can be with in the received signal

Cancellation, thus obtain

1203, owing to the distance of two via node R2 and R1 is nearer relatively, and source node is far away relatively to the distance of via node, so can be with S ₄Regard the method decoding S that disturbs and pass through interference eliminated as ₃

1204, decode S ₃After, once more will Cancellation, thus h obtained _Sr2S ₄

1205, because the weak parameter h of channel in the middle of source node and the via node R2 _Sr2Known, can directly decipher and obtain S ₄

1206, in the 5th time slot, the S that decoding is obtained ₃, S ₄Encoding obtains the energy normalized superposed signal, and concrete superposed signal can be expressed as: Then this superposed signal is transmitted, so that destination node can receive with another via node R1.

As can be seen from Figure 11; When the scheme that adopts the embodiment of the invention to provide is carried out collaboration communication; The reception signal of destination node D when having S-D link (link of source node to destination node), to receive signal when not having the S-D link be different, so destination node also need adopt different schemes when decoding; If source node can with the destination node direct communication, destination node will be received the aliasing signal of source node and forward relay, otherwise just only receive the signal from forward relay.

Specify as follows: with encoded packets length is 5 to be example, and the relay system of no S-D link, destination receive decoding matrix and be:

$\left[\begin{array}{c}{h}_{r1d}{s}_1\\ \sqrt{\frac{1}{2}}{h}_{r2d}{s}_1+\sqrt{\frac{1}{2}}{h}_{r2d}{s}_2\\ \sqrt{\frac{1}{2}}{h}_{r1d}{s}_2+\sqrt{\frac{1}{2}}{h}_{r1d}{s}_3\\ \sqrt{\frac{1}{2}}{h}_{r2d}{s}_3+\sqrt{\frac{1}{2}}{h}_{r2d}{s}_4\\ \sqrt{\frac{1}{2}}{h}_{r1d}{s}_4+\sqrt{\frac{1}{2}}{h}_{r1d}{s}_5\\ h_{r2d}{s}_5\end{array}\right]\left[\begin{array}{ccccc}{h}_{r1\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& & & & \\ \sqrt{\frac{1}{2}}{h}_{r2\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r2\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& & & \\ & \sqrt{\frac{1}{2}}{h}_{r1\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r1\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& & \\ & & \sqrt{\frac{1}{2}}{h}_{r2\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r2\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \\ & & & \sqrt{\frac{1}{2}}{h}_{r1\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r1d}\\ & & & & h_{r2d}\end{array}\right]\left[\begin{array}{c}{s}_1\\ s_2\\ s_3\\ s_4\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]=H\left[\begin{array}{c}{s}_1\\ s_2\\ s_3\\ s_4\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]$

The relay system that the S-D link is arranged, destination receive decoding matrix and are:

$\left[\begin{array}{c}{h}_{\mathrm{sd}}{s}_1\\ h_{r1d}{s}_1+h_{\mathrm{sd}}{s}_2\\ \sqrt{\frac{1}{2}}{h}_{r2d}{s}_1+\sqrt{\frac{1}{2}}{h}_{r2d}{s}_2+h_{\mathrm{sd}}{s}_3\\ \sqrt{\frac{1}{2}}{h}_{r1d}{s}_2+\sqrt{\frac{1}{2}}{h}_{r1d}{s}_3+h_{\mathrm{sd}}{s}_4\\ \sqrt{\frac{1}{2}}{h}_{r2d}{s}_3+\sqrt{\frac{1}{2}}{h}_{r2d}{s}_4+h_{\mathrm{sd}}{s}_5\\ \sqrt{\frac{1}{2}}{h}_{r1d}{s}_4+\sqrt{\frac{1}{2}}{h}_{r1d}{s}_5\\ h_{r2d}{s}_5\end{array}\right]\left[\begin{array}{ccccc}{h}_{\mathrm{sd}}& & & & \\ h_{r1d}& h_{\mathrm{<figure-callout\; id="1"\; label="sd"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">sd</figure-callout>}}& & & \\ \sqrt{\frac{1}{2}}{h}_{r2\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r2d}& h_{\mathrm{<figure-callout\; id="1"\; label="sd"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">sd</figure-callout>}}& & \\ & \sqrt{\frac{1}{2}}{h}_{r1\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r1d}& h_{\mathrm{<figure-callout\; id="1"\; label="sd"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">sd</figure-callout>}}& \\ & & \sqrt{\frac{1}{2}}{h}_{r2\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r2d}& h_{\mathrm{<figure-callout\; id="1"\; label="sd"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">sd</figure-callout>}}\\ & & & \sqrt{\frac{1}{2}}{h}_{r1\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">d</figure-callout>}}& \sqrt{\frac{1}{2}}{h}_{r1d}\\ & & & & h_{r2d}\end{array}\right]\left[\begin{array}{c}{s}_1\\ s_2\\ s_3\\ s_4\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]=H\left[\begin{array}{c}{s}_1\\ s_2\\ s_3\\ s_4\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]$

Wherein, the parameter of letter representation is the source in the above-mentioned decoding matrix, relaying R1, the channel fading parameters of relaying R2 and destination.

Behind the signal that receives 7 time slots, destination node is carried out combined decoding to these signals.Under the condition of complete known CSI (matrix H), the detection algorithm of using in the mimo system can use in the present invention, like the demodulation method of the iteration MMSE of serial interference elimination.

The embodiment of the invention also provides a kind of via node, and is shown in figure 13, and said via node comprises: receiving element 131, decoding unit 132, retransmission unit 133.

Wherein, Receiving element 131 is used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions; Said other via node forward signals comprise the signal that source node sends at last at least time slot, and the signal that said via node is transmitted is through the signal behind the supercomposed coding of energy normalized; Decoding unit 132 is used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal; Retransmission unit 133 is used for said source node is transmitted at next time slot at the signal of current time slots and the transmission of last time slot, and retransmission unit described in the embodiment of the invention 133 is transmitted said source node through behind the supercomposed coding of energy normalized at the signal of current time slots and the transmission of last time slot at next time slot.

In order can said superposed signal to be decoded, the concrete realization of decoding unit described in the embodiment of the invention 132 comprises: first cancellation module 1321, decoder module 1322, second cancellation module 1323.

Wherein, first cancellation module 1321 is used for before having decoded from said aliasing signal cancellation and obtains the signal that source node sends; The signal that decoder module 1322 is used for source node is sent in current time slots is as noise, obtains the signal that said source node sends at last time slot through interference elimination method decoding from the aliasing signal of the previous decoded signal of cancellation; Second cancellation module 1323 is used for obtaining the signal that said source node sends in current time slots from the signal that the said source node of aliasing signal cancellation of the previous decoded signal of cancellation sends at last time slot.

The embodiment of the invention also provides a kind of transmission system of collaboration communication, and is shown in figure 14, and said system comprises: source node 141, at least two via nodes 142 and destination nodes 143.

Wherein, source node 141 is used for sending signal in current time slots; At least two via nodes 142 are used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot; Also be used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal; And said source node transmitted at next time slot at the signal that current time slots and last time slot send; In general, via node 142 is transmitted said source node through behind the supercomposed coding of energy normalized at the signal of current time slots and the transmission of last time slot at next time slot; Destination node 143 is used to receive the signal that said source node that via node transmits sends at current time slots and last time slot, and decodes to the received signal and obtain the signal that source node sends.

When between source node 141 and destination node 143, not having the S-D link, destination node only need receive the signal of the said source node of via node forwarding in current time slots and the transmission of last time slot; If have the S-D link between source node 141 and the destination node 143; Then said destination node 143 also is used for the signal that the reception sources node sends in current time slots, and the aliasing signal formed of the signal that source node is sent in current time slots and the signal behind the said supercomposed coding is decoded and obtained the signal that source node sends.

Said via node 142 comprises following process when concrete decoding: the cancellation from said aliasing signal of via node 142 elder generations had before been decoded and had been obtained the signal that source node sends; The signal that then source node is sent in current time slots is as noise, obtains the signal that said source node sends at last time slot through interference elimination method decoding from the aliasing signal of the previous decoded signal of cancellation; And the signal that the said source node of cancellation sends at last time slot from the aliasing signal of the previous decoded signal of cancellation obtains the signal that said source node sends in current time slots.

The transmission method of the collaboration communication that the embodiment of the invention provides, via node and transmission system; The transmission method of collaboration communication need receive the signal of source node and other via nodes simultaneously in the embodiment of the invention in current time slots; Then the signal that receives is decoded and recompile or mapping and separation, and the mapping signal after recompile signal or the separation is transmitted.

Then be all to decode out when decoding with receiving the signal that all source nodes send in the signal; So that can source node be carried out supercomposed coding and forwarding at the signal of the transmission of two time slots at next time slot; When adopting this transmission plan, can improve decoding performance in the cooperation communication system.

Embodiment 3:

The embodiment of the invention provides a kind of transmission method of collaboration communication, and is identical among the utilization scene of the embodiment of the invention and the embodiment 2, and difference is to adopt in the present embodiment scheme of network code.

In embodiments of the present invention, it is shown in figure 15 that via node receives the transmission method of aliasing signal, and said method comprises:

1501, the aliasing signal formed of the network code signal transmitted of the signal that sends in current time slots of reception sources node and other via nodes, the network code signal that said other via nodes are transmitted comprises the signal that source node sends at last at least time slot.

1502, said aliasing signal is mapped to the network code signal that source node sends signal.

1503, separate decoding information from said the mapping the network code signal that.

1504, separate the network code signal of decoding information in next time slot forwarding.

The embodiment of the invention replaces under the system model identical with embodiment 2, we can consider in relaying, to utilize network code particularly the method for physical-layer network coding (PNC) carry out relaying and transmit.PNC is applied in the relay system that continues, and via node can be directly be mapped to the network code signal with the stack of desired signal that receives and interference signal and retransmits, and has reduced the computational complexity and because the issuable mistake of decoding of relaying like this.Simultaneously, also designed a kind of new interpretation method among the present invention to obtain source information because destination receives is network code signal (no S-D link) or the network code signal of relaying forwarding and the stack (the S-D link is arranged) of source signal.

In the relay system that continues; Source node all sends new information at each time slot; Two relayings are transmitting-receiving in turn, and each relaying all is mapped directly to the network code signal with the superposed signal of the interference signal of the source signal that receives and another relay transmission and transmits.What our supposing the system adopted is the modulation system of BPSK, and mapping relations can be like following table:

When trunk monitoring received signal y, β judged according to decision threshold, and the β value is following:

$\mathrm{\&beta;}=\frac{\exp \{-\frac{y-h_{1\left(2\right)}-h_0}{{2\mathrm{\&sigma;}}^2}\}+\exp \{-\frac{y+h_{1\left(2\right)}+h_0}{2{\mathrm{\&sigma;}}^2}\}}{\exp \{-\frac{y+h_{1\left(2\right)}-h_0}{2{\mathrm{\&sigma;}}^2}\}+\exp \{-\frac{y-h_{1\left(2\right)}+h_0}{2{\mathrm{\&sigma;}}^2}\}}$

When β greater than 1 the time, receive signal map and become-1; When β less than 1 the time, receive signal map and become 1.So channel fading parameters h between complete known relaying _{1 (2)}And source node is to via node channel fading parameters h ₀The time, the variation of channel quality between the relaying (distance changes) just makes corresponding decision threshold change.If in the network code signal after the mapping the known signal section of relaying is arranged, can retransmit again later on through this part signal of XOR cancellation, but need not to decode to received signal.

Expressed among Figure 16 after the employing embodiment of the invention, source node transfer encoding packet length is 5 network code scheme transmission time slot figure.

Be example with via node R2 among Figure 16 the 4th time slot reception condition below, the process that the via node decoding is transmitted again is shown in figure 17, and this method comprises:

1701, in the 4th time slot, via node R2 receives the signal S that source node sends ₄And the network code signal of another via node R1 transmission

1702, via node R2 is directly with the signal map that receives becomes

1703, owing to decoded S between the R2 ₂So, can be with S ₂Separate, thereby obtain

The network code signal.

1704, in the 5th time slot; transmits with resultant network code signal, so that destination node or R1 can receive.

As can be seen from Figure 16; When the scheme that adopts the embodiment of the invention to provide is carried out collaboration communication; The reception signal of destination node D when having S-D link (link of source node to destination node), to receive signal when not having the S-D link be different, so destination node also need adopt different schemes when decoding; If source node can with the destination node direct communication, destination node will be received the aliasing signal of source node and forward relay, otherwise just only receive the signal from forward relay.

Specify as follows: with encoded packets length is 5 to be example, and the relay system of no S-D link, destination receive decoding matrix and be:

$\left[\begin{array}{c}{s}_1\\ s_2\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\&CirclePlus;s_3\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;s_4\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_4\&CirclePlus;s_5\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]\&DoubleRightArrow;G=\left[\begin{array}{ccccc}1& & & & \\ & 1& & & \\ & 1& 1& & \\ & & 1& 1& \\ & & 1& 1& 1\\ & & & & 1\end{array}\right]$

The relay system that the S-D link is arranged, destination receive decoding matrix and are:

$\left[\begin{array}{c}{s}_1\\ {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">s</figure-callout>}}_1+s_2\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_2+s_3\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\&CirclePlus;{\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3+s_4\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_4+s_5\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_4\&CirclePlus;s_5\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]\&DoubleRightArrow;\left[\begin{array}{c}{s}_1\\ {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="HDA0000049456700000102.png,HDA0000049456700000133.png"\; state="\{\{state\}\}">s</figure-callout>}}_1\&CirclePlus;s_2\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\&CirclePlus;s_3\\ {\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_2\&CirclePlus;{\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;s_4\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_4\&CirclePlus;s_5\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA0000049456700000011.png,HDA0000049456700000071.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\&CirclePlus;{\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_4\&CirclePlus;s_5\\ {\mathrm{<figure-callout\; id="5"\; label="s"\; filenames="HDA0000049456700000071.png,HDA0000049456700000102.png"\; state="\{\{state\}\}">s</figure-callout>}}_5\end{array}\right]\&DoubleRightArrow;G=\left[\begin{array}{ccccc}1& & & & \\ 1& 1& & & \\ & 1& 1& & \\ & 1& 1& 1& \\ & & 1& 1& 1\\ & & 1& 1& 1\\ & & & & 1\end{array}\right]$

The Gaussian elimination method that the decoding of destination can adopt information that utilization deciphered and network code signal XOR to obtain new source information, translate successively each time slot source information of sending.But when using this traditional interpretation method, after the information decoding mistake of a time slot, ensuing decode results all can be made mistakes.We consider that a kind of different multi-slot that utilizes receives the method for combined signal decoding: receive the signal of some when destination after, these signals can be regarded source signal as and be encoded into the check digit code word that generator matrix is the LDGM sign indicating number of G.Generator matrix G is determined by the network code signal form that receives.Therefore we can recover source information through the iterative decoding algorithm of separating the LDGM sign indicating number.Method before being different from, this combined decoding method can obtain the coding gain of LDGM sign indicating number.The LLR value of input iterative decoder is:

When signal is x _iOr During form, the LLR of input decoder (y) is 4h _{1 (2)}Y/N ₀, when receiving signal do Form the time, the input LLR (y) be:

$L\left(y\right)=\log \frac{\exp \{-\frac{{(y-h_{1\left(2\right)}-h_0)}^2}{N_0}\}+\exp \{-\frac{{(y+h_{1\left(2\right)}+h_0)}^2}{N_0}\}}{\exp \{-\frac{{(y-h_{1\left(2\right)}+h_0)}^2}{N_0}\}+\exp \{-\frac{{(y+h_{1\left(2\right)}-h_0)}^2}{N_0}\}}$

The embodiment of the invention also provides a kind of via node, and is shown in figure 18, and said via node comprises: receiving element 181, map unit 182, separative element 183, retransmission unit 184.

Wherein, Receiving element 181 is used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via nodes transmit is formed, and the network code signal that said other via nodes are transmitted comprises the signal that source node sends at last at least time slot; Map unit 182 is used for said aliasing signal is mapped to the network code signal that source node sends signal; Separative element 183 is used for separating decoding information from the said network code signal that shines upon; Said retransmission unit 184 is used for separating the network code signal of decoding information in next time slot forwarding.

The embodiment of the invention also provides a kind of transmission system of collaboration communication; Shown in figure 19; Said system comprises: source node 191, via node 192 and destination node 193; Generally at least two of via nodes in the present embodiment are that example describes with two via nodes among Figure 19, but not as the qualification of protection range of the present invention.

Wherein, source node 191 is used for sending signal in current time slots;

At least two via nodes 192 are used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via node transmit is formed, and the network code signal that said other via node is transmitted comprises the signal that source node sends at last at least time slot; Via node 192 also was used for before next time slot is transmitted said network code signal, separated decoding information from said the mapping the network code signal that, and transmitted at next time slot and to separate the network code signal of decoding information; Destination node 193 is used to receive the network code signal that via node 192 is transmitted, and the network code signal that receives decoded obtains the signal that source node sends.

Destination node described in the embodiment of the invention 193 also is used for the signal that the reception sources node sends in current time slots, and the aliasing signal formed of the signal that source node is sent in current time slots and via node forward signal is decoded and obtained the signal of source node transmission.

And in the embodiment of the invention, said destination node 193 is after receiving the signal of predetermined quantity, and the mode of employing combined decoding is decoded and obtained the signal that source node sends.

The transmission method of the collaboration communication that the embodiment of the invention provides, via node and transmission system; The transmission method of collaboration communication need receive the signal of source node and other via nodes simultaneously in the embodiment of the invention in current time slots; Then the signal that receives is decoded and recompile or mapping and separation, and the mapping signal after recompile signal or the separation is transmitted.

When shining upon; Need aliasing signal be mapped to the network code signal that source node sends signal; That is to say in the aliasing signal signal terms of the signal correction that any one and source node send, all need be mapped in the network code signal, and separate decoding information and transmit then; When adopting this transmission plan, can improve decoding performance in the cooperation communication system.

Embodiment 4:

The embodiment of the invention also provides a kind of transmission method of collaboration communication, and is shown in figure 20, and said method comprises:

2001, before the system transmissions process begins, obtain first channel quality and the second channel quality between the via node between equivalent channel quality eSNR, source node S and the via node R between source node S and the destination node D.

During concrete the realization, the concrete scheme of this process is: before the system transmissions process began, source node and via node took different time-gap respectively and send training sequence.Through training sequence, via node can obtain own and source node and and another via node between channel quality information, be equivalent to obtain channel quality and the channel quality between the via node between source node and the via node.Simultaneously destination node also can obtain and source node and and via node between channel quality information; And destination node gives via node with the channel quality information feedback that obtains, and via node can obtain the equivalent channel quality eSNR between source node and the destination node.

2002, the bad channel quality between said first channel quality of calculating and the second channel quality; Channel quality between source node S and the via node R is used SNR _SRExpression, channel quality is used SNR between the via node _RRExpression, concrete bad channel quality Δ SNR=SNR _RR-SNR _SR

2003, whether judge said equivalent channel quality eSNR less than first predetermined threshold, if eSNR less than first predetermined threshold, then carries out 2005; If eSNR is not less than first predetermined threshold, then carry out 2004.

2004, judge that whether said bad channel quality Δ SNR is greater than second predetermined threshold; If Δ SNR greater than second predetermined threshold, then carries out 2005; If Δ SNR is not more than second predetermined threshold, then carry out 2006.

2005, the transmission method according to the confession collaboration communication that provides among the embodiment 2 carries out collaboration communication.

2006, the transmission method according to the confession collaboration communication that provides among the embodiment 3 carries out collaboration communication.

Each internodal transmission channel environment is long relevant with transmission time slot in first predetermined threshold that adopts in the embodiment of the invention and second predetermined threshold and the system.

The embodiment of the invention is the integrated use that combines embodiment 2 and embodiment 3; In the transmission system of reality; Relaying can be selected different trunking plans according to effective SNR of difference in channel quality between S-R and the R-R and destination reception, to reach system transmissions performance preferably.Concrete scheme is: before the system transmissions process began, source and relaying took different time-gap respectively and send training sequence.Through training sequence, relaying can obtain own and source node, and the channel quality information between another via node.Destination node also can obtain and source node simultaneously, and the channel quality information between the via node, and gives via node with this feedback information.Relaying is according to the bad channel quality Δ SNR=SNR between S-R and the R-R _RR-SNR _SRAnd the reception of destination node equivalence SNR (eSNR), it still is the relaying strategy of supercomposed coding that network code is used in decision

, adopt by relaying the scheme of supercomposed coding certain diversity gain can be provided when transmitting with respect to conventional method.When source node was little to the difference in channel quality between via node and the via node, relaying adopted the method for network code can avoid the excessive problem of decode error under the high SNR.Relaying is selected corresponding transmission plan according to source node to the transmission SNR of difference in channel quality between via node and the via node and system, has reduced the error rate of system effectively.Through emulation the gain that technical scheme of the present invention is brought is described below.Figure 21 is the illustraton of model of analogue system, and wherein S representes source node, and R1 and R2 represent via node, and D representes destination node, and under the situation of taking into account system experience rayleigh fading channel, the distance between fixing each node is in Figure 21: S-R, and R-D is apart from 150m; R-R distance and S-D distance satisfy:

$l_{\mathrm{SD}}=2\sqrt{{l_{\mathrm{SR}}}^2-{(l_{\mathrm{RR}}/2)}^2}$

Shown in figure 21.The decline parameter h of arbitrary channel can be expressed as:

$y=\mathrm{hx}+n=h_r\sqrt{l^{-\mathrm{\&alpha;}}}\sqrt{P}x+n$

L wherein ^-αPath loss when the representation node distance is l, α is 2 to 4 parameter, gets 4 here.P is the transmitted power of node, in emulation, is normalized to 1.h _rBe normalized Rayleigh fading parameter.Do not adopt chnnel coding.Suppose that source transmission package number is 11, after source node stopped to send data, two relayings also will each be transmitted once.In this emulation, we receive BER (the test error code ratio) performance that equivalent SNR (eSNR) comes comparison system according to system.

If receiving matrix is H, the nonzero element h among the H _IjExplained that receiving terminal has received effective source information S at i time slot _jSignal component, the equivalent SNR that receives this part signal is h _IjSNR.If the nonzero element set is C among the H _H, then the equivalent SNR of system can be expressed as:

$\mathrm{ESNR}=\frac{\underset{h_{\mathrm{Ij}}\&Element;C_H}{\mathrm{\&Sigma;}}{h}_{\mathrm{Ij}}}{\left|C_H\right|}\mathrm{SNR};$ Wherein, receive $\mathrm{SNR}=\frac{{\left|h_r\right|}^2{l_{\mathrm{SD}}}^{-\mathrm{\&alpha;}}P}{N_0}\&ap;\frac{{l_{\mathrm{SD}}}^{-4}}{N_0}.$

Among Figure 22 when R-R channel quality between the relaying better (bigger) when (R-R is at a distance of 10m), the superposed signal that this moment, relaying can correctly separate reception with S-R channel quality (S-R is at a distance of 150m) difference.The method of supercomposed coding relaying has best performance.

When channel quality is relatively poor between the relaying (when being more or less the same with the S-R channel quality), under low received signal to noise ratio (approximately less than 20dB), the supercomposed coding trunking method has best performance among Figure 23; The method of repeated encoding and supercomposed coding relaying the decoding error platform can occur under high received signal to noise ratio, and the method for network code relaying still has preferable performance at this moment.

When reception SNR was 25dB among Figure 24, when R-R (between relaying and the relaying) close together (approximately less than 35m), supercomposed coding scheme better performances adopted the network code scheme better during the R-R distance.

Through the description of above execution mode, the those skilled in the art can be well understood to the present invention and can realize by the mode that software adds essential common hardware, can certainly pass through hardware, but the former is better execution mode under a lot of situation.Based on such understanding; The part that technical scheme of the present invention contributes to prior art in essence in other words can be come out with the embodied of software product, and this computer software product is stored in the storage medium that can read, like the floppy disk of computer; Hard disk or CD etc.; Comprise some instructions with so that computer equipment (can be personal computer, server, the perhaps network equipment etc.) carry out the described method of each embodiment of the present invention.

The above; Be merely embodiment of the present invention, but protection scope of the present invention is not limited thereto, any technical staff who is familiar with the present technique field is in the technical scope that the present invention discloses; Can expect easily changing or replacement, all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion by said protection range with claim.

Claims (13)

1. the transmission method of a collaboration communication is characterized in that, comprising:

The reception sources node is at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot;

Decoding obtains the signal that signal that said source node sends in current time slots and source node send at last at least time slot from said aliasing signal;

Said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, obtain the signal behind the supercomposed coding;

Signal behind the said supercomposed coding is transmitted at next time slot.

2. the transmission method of collaboration communication according to claim 1 is characterized in that, said from said aliasing signal decoding obtain signal and source node that said source node sends in current time slots and comprise at the signal that last at least time slot sends:

Cancellation had before been decoded and had been obtained the signal that source node sends from said aliasing signal;

The signal that source node is sent in current time slots is as noise, obtains the signal that said source node sends at last time slot through interference elimination method decoding from the aliasing signal of the previous decoded signal of cancellation;

The signal that the said source node of cancellation sends at last time slot from the aliasing signal of the previous decoded signal of cancellation obtains the signal that said source node sends in current time slots.

3. a via node is characterized in that, comprising:

Receiving element is used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot;

Decoding unit is used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal;

Coding unit is used for said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, and obtains the signal behind the supercomposed coding;

Retransmission unit is used for the signal behind the said supercomposed coding is transmitted at next time slot.

4. via node according to claim 3 is characterized in that, said decoding unit comprises:

First cancellation module, being used for before having decoded from said aliasing signal cancellation obtains the signal that source node sends;

Decoder module, the signal that is used for source node is sent in current time slots be as noise, obtains the signal that said source node sends at last time slot through interference elimination method decoding from the aliasing signal of the previous decoded signal of cancellation;

Second cancellation module is used for obtaining the signal that said source node sends in current time slots from the signal that the said source node of aliasing signal cancellation of the previous decoded signal of cancellation sends at last time slot.

5. the transmission system of a collaboration communication is characterized in that, comprising:

Source node is used for sending signal in current time slots;

At least two via nodes are used for the reception sources node at the signal of current time slots transmission and the aliasing signal of other via node forward signals compositions, and said other via node forward signals comprise the signal that source node sends at last at least time slot; Also be used for obtaining the signal that signal that said source node sends in current time slots and source node send at last at least time slot from the decoding of said aliasing signal; Said source node is carried out supercomposed coding at the signal that current time slots and last time slot send, obtain the signal behind the supercomposed coding; Signal behind the said supercomposed coding is transmitted at next time slot;

Destination node is used to receive the signal behind the supercomposed coding that via node transmits, and decodes to the received signal and obtain the signal that source node sends.

6. the transmission system of collaboration communication according to claim 5; It is characterized in that; Said destination node also is used for the signal that the reception sources node sends in current time slots, and the aliasing signal formed of the signal that source node is sent in current time slots and the signal behind the said supercomposed coding is decoded and obtained the signal that source node sends.

7. the transmission system of collaboration communication according to claim 5 is characterized in that, said via node is used for before having decoded from said aliasing signal cancellation and obtains the signal that source node sends; The signal that source node is sent in current time slots is as noise, obtains the signal that said source node sends at last time slot through interference elimination method decoding from the aliasing signal of the previous decoded signal of cancellation; And the signal that the said source node of cancellation sends at last time slot from the aliasing signal of the previous decoded signal of cancellation obtains the signal that said source node sends in current time slots.

8. the transmission method of a collaboration communication is characterized in that, comprising:

The aliasing signal that the network code signal that the reception sources node is transmitted at signal and other via nodes of current time slots transmission is formed, the network code signal that said other via nodes are transmitted comprise the signal of source node in last at least time slot transmission;

Said aliasing signal is mapped to the network code signal of the signal of source node transmission;

Separate decoding information from said the mapping the network code signal that;

Separate the network code signal of decoding information in next time slot forwarding.

9. a via node is characterized in that, comprising:

Receiving element; Be used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via nodes transmit is formed, the network code signal that said other via nodes are transmitted comprises the signal that source node sends at last at least time slot;

Map unit is used for said aliasing signal is mapped to the network code signal that source node sends signal;

Separative element is used for separating decoding information from the said network code signal that shines upon;

Retransmission unit is used for separating the network code signal of decoding information in next time slot forwarding.

10. the transmission system of a collaboration communication is characterized in that, comprising:

Source node is used for sending signal in current time slots;

At least two via nodes; Be used for the aliasing signal that network code signal that signal that the reception sources node sends in current time slots and other via node transmit is formed, the network code signal that said other via node is transmitted comprises the signal that source node sends at last at least time slot; Also be used for said aliasing signal is mapped to the network code signal that source node sends signal, separate decoding information, and transmit at next time slot and to separate the network code signal of decoding information from said the mapping the network code signal that;

Destination node is used to receive the network code signal that via node is transmitted, and the network code signal that receives decoded obtains the signal that source node sends.

11. the transmission system of collaboration communication according to claim 10; It is characterized in that; Said destination node also is used for the signal that the reception sources node sends in current time slots, and the aliasing signal formed of the signal that source node is sent in current time slots and via node forward signal is decoded and obtained the signal of source node transmission.

12. the transmission system of collaboration communication according to claim 10 is characterized in that, said destination node is after receiving the signal of predetermined quantity, and the mode of employing combined decoding is decoded and obtained the signal that source node sends.

13. the transmission method of a collaboration communication is characterized in that, comprising:

Obtain first channel quality and the second channel quality between the via node between equivalent channel quality, source node and the via node between source node and the destination node;

Calculate the bad channel quality between said first channel quality and the said second channel quality;

In said equivalent channel quality during, carry out collaboration communication according to the transmission method of collaboration communication described in claim 1 or 2 less than first predetermined threshold;

When said equivalent channel quality is not less than first predetermined threshold, judge that whether said bad channel quality is greater than second predetermined threshold;

In said bad channel quality during, carry out collaboration communication according to the transmission method of collaboration communication described in claim 1 or 2 greater than second predetermined threshold;

When said bad channel quality is not more than second predetermined threshold, carry out collaboration communication according to the transmission method of the said collaboration communication of claim 8.

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