CN102387114A - Multi-hop relay OFDM information transmission method facing to distributed wireless sensor network - Google Patents

Multi-hop relay OFDM information transmission method facing to distributed wireless sensor network Download PDF

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CN102387114A
CN102387114A CN2011103858491A CN201110385849A CN102387114A CN 102387114 A CN102387114 A CN 102387114A CN 2011103858491 A CN2011103858491 A CN 2011103858491A CN 201110385849 A CN201110385849 A CN 201110385849A CN 102387114 A CN102387114 A CN 102387114A
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ofdm
mimo
hop
signal
relay
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刘俊
周小林
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Fudan University
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Abstract

The invention belongs to the field of wireless communication technology, and particularly relates to a multi-hop relay OFDM (Orthogonal Frequency Division Multiplexing) information transmission method facing to a distributed wireless sensor network. A multi-hop MIMO (Multiple-Input Multiple-Output)-OFDM relay system model is adopted, an antenna array serves as a relay node, and transmission is conducted in different time slots according to different odd and even hop numbers during relay in a double-time-slot conveyor belt manner; and power of sub-channels corresponding to sub-carriers is distributed by adopting water-filling algorithm, so that the end-to-end throughput of an MIMO-OFDM relay system can reach the maximum. By adopting the method provided by the invention, the channel capacity can be greatly improved under the premise of fundamentally eliminating ISI (Inter Symbol Interference), and the design complexity of a receiver in multi-path environments is lowered.

Description

Multi-hop relay OFDM information transferring method towards distributed wireless sensor network
Technical field
The invention belongs to wireless communication technology field, be specifically related to a kind of multi-hop relay OFDM information transferring method towards distributed wireless sensor network.
Background technology
In radio communication, multipath fading is the key factor that influences communication quality, and diversity technique can be used for overcoming multipath fading.Diversity technique mainly comprises time diversity, frequency diversity, space diversity and polarization diversity.The signal that appears as of MIMO (Multiple-Input Multiple-Output) provides space diversity, thereby eliminates multipath effect, overcome the bit error rate that signal fadeout reduces signal, the reliability of enhancing signal.
Distributed sensing network WSN (Wireless Sensor Network) can promote the monitoring function for physical environment far away; Just receiving concern more and more widely, seeking etc. at other field such as intelligent space, medical system and machine also all has potential using value.WSN is made up of a lot of distributed sensing nodes, utilization multi-hop relay technology, and through the cooperation between the sensing node, and the online treatment at each node place of information, WSN can greatly promote the accuracy of transmission information
OFDM (Orthogonal Frequency Division Multiplexing); It is orthogonal frequency division multiplexi; Be a kind of Parallel Digital modulation technique, through with the high-speed data-flow string and convert many slow datas stream to, and be modulated to the high-speed transfer of the enterprising line data of a plurality of orthogonal sub-carriers.The OFDM technology has stronger the anti-multipath decline ability and the higher availability of frequency spectrum.
The multi-hop relay wireless network of MIMO-OFDM technology has become the research focus in the wireless communication field, and as the physical-layer techniques that the next generation wireless communication network will generally adopt, MIMO-OFDM multi-hop relay Study on Technology will be extremely meaningful.The OFDM technology is applied in the mimo system, can under the prerequisite of the basic ISI of elimination (Inter Symbol Interference), greatly improves channel capacity, also reduced the design complexities of receiver under multi-path environment simultaneously.
A key factor that influences the end-to-end throughput of multihop relay system is a power.Thereby how effectively distribute limited power in system reach end-to-end throughput-maximized be important research direction at present.The present invention proposes a kind of multi-hop MIMO-OFDM method of using water-filling algorithm, utilize water-filling algorithm that subcarrier and subchannel are carried out power division,, can obtain more excellent end-to-end system goodput compared to the method for traditional average power allocation.
Summary of the invention
The objective of the invention is to propose a kind of multi-hop MIMO-OFDM method of using water-filling algorithm, subcarrier and subchannel are carried out power division, be superior to the method for traditional average power allocation, and obtain more excellent end-to-end system goodput.
The multi-hop MIMO-OFDM method of the application water-filling algorithm that the present invention proposes; Adopt multi-hop MIMO-OFDM relay system model; Use aerial array as via node, adopt the mode of two slot transmission bands, the odd even jumping figure is different and just transmit at different time-gap during according to relaying; And the use water-filling algorithm, the sub-channel power that all subcarriers are corresponding is carried out power division, make the end-to-end throughput of MIMO-OFDM relay system reach maximum.
Shown in Figure 1 is a kind of typically based on the multihop relay system model of MIMO-OFDM technology, and three types module is wherein arranged.BS represents the base station, signal source end.Aerial array has the function that receives signal and transmit as via node.MS represents mobile radio station, signal terminal point.If this system one total
Figure 365448DEST_PATH_IMAGE001
jumps; Forwarding through
Figure 307996DEST_PATH_IMAGE002
individual via node is transferred to MS with signal from BS.Each jumping all is a mimo system; And in whole system, used the OFDM technology, utilize
Figure 57515DEST_PATH_IMAGE003
individual orthogonal sub-carriers carrying signal.These form a MIMO-OFDM multihop relay system.
(1) transmission of multihop relay system
Adopt the mode of two slot transmission; Promptly at first time slot
Figure 478132DEST_PATH_IMAGE004
; All odd number of hops are carried out the signal transmission; And at second time slot
Figure 13019DEST_PATH_IMAGE005
; All even numbers are jumped into capable signal transmission; Transmission performance that thus can enhanced system is especially for the jumping figure system with more.
Exist
Figure 860889DEST_PATH_IMAGE006
individual orthogonal sub-carriers to be used for carrying signal in the supposing the system; Then all subcarriers are distributed to all odd number of hops or even number respectively and are jumped into the row transmission in two time slots, satisfy condition as follows:
Figure 599169DEST_PATH_IMAGE007
（1）
Figure 885794DEST_PATH_IMAGE008
（2）。
(2) the end-to-end throughput of multi-hop MIMO-OFDM relay system
In jumping at
Figure 212870DEST_PATH_IMAGE009
; root transmitting antenna,
Figure 286578DEST_PATH_IMAGE011
root reception antenna are arranged; Can supply the sub-carrier number of modulation signal individual for
Figure 862047DEST_PATH_IMAGE012
; The mimo channel decline matrix
Figure 561199DEST_PATH_IMAGE014
of corresponding dimension of each subcarrier then;
Figure 461022DEST_PATH_IMAGE015
can get the capacity that subcarrier carried by appendix and be:
Figure 374806DEST_PATH_IMAGE017
（3）
So the channel capacity that
Figure 63276DEST_PATH_IMAGE009
jumps is:
（4）
Wherein,
Figure 367667DEST_PATH_IMAGE019
carries out the number that SVD decomposes back gained characteristic value to mimo channel decline matrix, and promptly a number of sub-carrier is transmitted in mimo system and is equivalent in
Figure 586159DEST_PATH_IMAGE020
individual parallel SISO subchannel, transmit.The power of corresponding subchannel of subcarrier
Figure 300704DEST_PATH_IMAGE016
is distributed in expression; is the noise power of this subchannel,
Figure 328200DEST_PATH_IMAGE024
then for characterizing the characteristic value of this subchannel.
The channel throughput that
Figure 486649DEST_PATH_IMAGE009
jumps is:
Figure 932674DEST_PATH_IMAGE025
(5)
Wherein,
Figure 375025DEST_PATH_IMAGE026
(6)
So the end-to-end throughput of multi-hop MIMO-OFDM relay system is:
Figure 513883DEST_PATH_IMAGE027
(7)?。
(3) water injection power is distributed
The corresponding sub-channel power of all subcarriers is carried out water injection power distributes; The noise power of at first known each subchannel is
Figure 159627DEST_PATH_IMAGE028
; Gross power is
Figure 409343DEST_PATH_IMAGE029
;
Figure 207666DEST_PATH_IMAGE030
is the characteristic value of each subchannel, it carried out descending arrangement obtains
Figure 579742DEST_PATH_IMAGE031
individual
Figure 964980DEST_PATH_IMAGE032
.Initialization; Introduce
Figure 80703DEST_PATH_IMAGE033
as iterative parameter; Make
Figure 920484DEST_PATH_IMAGE034
, calculate subsequently:
Figure 214193DEST_PATH_IMAGE035
(8)
Value; When
Figure 568951DEST_PATH_IMAGE036
; Will; Otherwise; Then put ; And
Figure 431919DEST_PATH_IMAGE038
; Continue
Figure 83480DEST_PATH_IMAGE039
of statistical formula (8); And the like, till calculating all
Figure 191114DEST_PATH_IMAGE040
.
Figure 399372DEST_PATH_IMAGE040
distributed to corresponding subchannel.
It is following that the present invention invents advantage:
(1) MIMO-OFDM can greatly improve channel capacity under the prerequisite of the basic ISI of elimination, reduces the design complexities of receiver under multi-path environment.
(2) will inherit the advantage of MIMO-OFDM technology own simultaneously based on the MIMO-OFDM network of multi-hop relay, effectively reduce the large scale path loss of signal through modes such as relaying amplifications.
(3) utilize the power allocation scheme of the water-filling algorithm of subchannel characteristic value computing, optimized the poorest throughput end to end, thereby improved the entire system throughput.
Description of drawings
Fig. 1 is a multi-hop MIMO-OFDM relay system.
Fig. 2 is typical four jumping MIMO-OFDM relay systems.
Fig. 3 analyzes conclusion one (2*2*2 MIMO-OFDM system, traditional average algorithm and water-filling algorithm performance difference) (sub-carrier number is 256, adopts the transmission manner of two time slots) for system emulation of the present invention.
Fig. 4 analyzes conclusion two (4*4*4 MIMO-OFDM system, traditional average algorithm and water-filling algorithm performance difference) (sub-carrier number is 256, adopts the transmission manner of two time slots) for system emulation of the present invention.
Fig. 5 analyzes conclusion three (8*8*8 MIMO-OFDM system, traditional average algorithm and water-filling algorithm performance difference) (sub-carrier number is 256, adopts the transmission manner of two time slots) for system emulation of the present invention.
Fig. 6 analyzes conclusion four (2*2*2*2*2 MIMO-OFDM system, traditional average algorithm and water-filling algorithm performance difference) (sub-carrier number is 64, adopts the transmission manner of two time slots) for system emulation of the present invention.
Fig. 7 analyzes conclusion four (4*4*4*4*4 MIMO-OFDM system, traditional average algorithm and water-filling algorithm performance difference) (sub-carrier number is 64, adopts the transmission manner of two time slots) for system emulation of the present invention.
Fig. 8 water-filling algorithm flow chart.
Embodiment
The multi-hop MIMO-OFDM method of the application water-filling algorithm that the present invention proposes, its practical implementation step is following:
1, obtain channel characteristic value, be designated as
Figure 948165DEST_PATH_IMAGE031
individual
Figure 98524DEST_PATH_IMAGE032
.
Calculate the mimo channel decline matrix of corresponding dimension of each subcarrier;
Figure 607533DEST_PATH_IMAGE042
; Calculate pairing characteristic value of matrix
Figure 597672DEST_PATH_IMAGE030
, and carry out descending ordering formation individual
Figure 964379DEST_PATH_IMAGE032
.
2, utilize the water-filling algorithm dispensed to give the power of each subchannel
Computing formula (8); During as
Figure 487764DEST_PATH_IMAGE044
; With
Figure 963614DEST_PATH_IMAGE045
; Otherwise; Then put ; And
Figure 808259DEST_PATH_IMAGE038
; Continue
Figure 999200DEST_PATH_IMAGE039
of statistical formula (8); And the like, till calculating all
Figure 599946DEST_PATH_IMAGE047
.
Figure 125605DEST_PATH_IMAGE047
distributed to corresponding subchannel.
3, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7 are last simulation analysis result, wherein:
Fig. 3 shows, the channel capacity that adopts the inventive method to distribute power to obtain obviously is superior to the method for average and distributes power, and in signal to noise ratio during greater than 35dB, two kinds of method throughputs are more or less the same.
Fig. 4, Fig. 5 show that the difference between the throughput of the channel capacity gained that employing the inventive method distribution power obtains and the throughput of mean allocation power gained is more obvious.
Fig. 6 shows that when increasing jumping figure, when the receiving terminal signal to noise ratio was low, the throughput of system that water flood distributes power to obtain obviously was superior to the method for average and distributes power, after the receiving terminal signal to noise ratio is greater than 15dB, adopts the increase DeGrain of water-filling algorithm to capacity.
Fig. 7 shows that the increase of number of antennas is corresponding to have improved the end-to-end throughput of MIMO-OFDM system, and water flood distributes power to be superior to the end-to-end throughput that the method for average is distributed the power gained all the time.
Appendix:
In this appendix, will derive in detail and utilize water-filling algorithm computing system capacity.
The channel capacity of known mimo system is:
Figure 784513DEST_PATH_IMAGE048
（A-1）
Wherein
Figure 282490DEST_PATH_IMAGE032
is channel characteristic value;
Figure 850875DEST_PATH_IMAGE049
is the element on transmitted power flexible strategy matrix
Figure 67092DEST_PATH_IMAGE050
diagonal; The power flexible strategy of
Figure 762647DEST_PATH_IMAGE022
individual independent subchannels are distributed in expression; And satisfy
Figure 177448DEST_PATH_IMAGE051
; for distributing to the power of
Figure 666253DEST_PATH_IMAGE052
root antenna, is the noise power of subchannel.
Suppose
Figure 434806DEST_PATH_IMAGE054
; Be used for representing to distribute to the power of
Figure 548255DEST_PATH_IMAGE022
subchannel, optimization problem turns to finds the solution:
Figure 68766DEST_PATH_IMAGE056
（A-2）。
Utilize method of Lagrange multipliers, introduce function
Figure 208891DEST_PATH_IMAGE057
:
Figure 493242DEST_PATH_IMAGE058
（A-3）
Each
Figure 702506DEST_PATH_IMAGE059
asked local derviation:
Figure 223672DEST_PATH_IMAGE061
Figure 741241DEST_PATH_IMAGE062
Figure 454114DEST_PATH_IMAGE063
（A-4）
Figure 82541DEST_PATH_IMAGE062
Figure 118630DEST_PATH_IMAGE064
。
Suppose
Figure 59298DEST_PATH_IMAGE065
,
Figure 243154DEST_PATH_IMAGE031
the individual equality addition with correspondence can obtain so:
Figure 426005DEST_PATH_IMAGE066
（A-5）
Thus:
Figure 644497DEST_PATH_IMAGE067
（A-6）
The value that makes this
Figure 441552DEST_PATH_IMAGE031
individual equality all is zero, then:
（A-7）。
Channel allocation power is non-negative in this realistic model of MIMO; Therefore introducing expression formula
Figure 332202DEST_PATH_IMAGE069
representes that is expressed as thus:
Figure 123889DEST_PATH_IMAGE070
（A-8）。
Figure 552113DEST_PATH_IMAGE031
individual characteristic value is pressed sequence arrangement from small to large; Introduce letter then as iterative parameter; Putting its initial value is 1, and corresponding
Figure 706068DEST_PATH_IMAGE039
of calculating:
Figure 844926DEST_PATH_IMAGE071
（A-9）。
The substitution formula successively with
Figure 225092DEST_PATH_IMAGE032
:
Figure 553436DEST_PATH_IMAGE072
（A-10）。
Relatively whether it is negative; If for bearing then putting
Figure 538709DEST_PATH_IMAGE059
is 0; Otherwise; Putting
Figure 910785DEST_PATH_IMAGE059
is the value that calculates; And the like, form the process of similar water filling.

Claims (4)

1. multi-hop relay OFDM information transferring method towards distributed wireless sensor network; It is characterized in that adopting multi-hop MIMO-OFDM relay system model; Use aerial array as via node; Adopt the mode of two slot transmission bands, the odd even jumping figure is different and just transmit at different time-gap during according to relaying; Use water-filling algorithm, the sub-channel power that all subcarriers are corresponding is carried out power division, make the end-to-end throughput of MIMO-OFDM relay system reach maximum.
2. the described method of claim 1 is characterized in that described multi-hop MIMO-OFDM relay system model, and three types module is wherein arranged: BS represents the base station, signal source end; Aerial array has the function that receives signal and transmit as via node; MS represents mobile radio station, signal terminal point; If this system one total
Figure 2011103858491100001DEST_PATH_IMAGE002
jumps; Forwarding through
Figure 2011103858491100001DEST_PATH_IMAGE004
individual via node is transferred to MS with signal from BS; Each jumping all is a mimo system; And in whole system, used the OFDM technology, utilize
Figure 2011103858491100001DEST_PATH_IMAGE006
individual orthogonal sub-carriers carrying signal; These form a MIMO-OFDM multihop relay system.
3. method according to claim 2; The mode that it is characterized in that the two slot transmission of said employing; Promptly at first time slot
Figure 2011103858491100001DEST_PATH_IMAGE008
; All odd number of hops are carried out the signal transmission; And at second time slot
Figure 2011103858491100001DEST_PATH_IMAGE010
, all even numbers are jumped into capable signal transmission;
Exist
Figure 2011103858491100001DEST_PATH_IMAGE012
individual orthogonal sub-carriers to be used for carrying signal in the supposing the system; Then all subcarriers are distributed to all odd number of hops or even number respectively and are jumped into the row transmission in two time slots, satisfy condition as follows:
Figure 2011103858491100001DEST_PATH_IMAGE014
（1）
Figure 2011103858491100001DEST_PATH_IMAGE016
（2）。
4. method according to claim 3 is characterized in that said the corresponding sub-channel power of all subcarriers being carried out power division, and concrete steps are:
At first; The noise power of known each subchannel is
Figure 2011103858491100001DEST_PATH_IMAGE018
; Gross power is
Figure 2011103858491100001DEST_PATH_IMAGE020
;
Figure 2011103858491100001DEST_PATH_IMAGE022
is the characteristic value of each subchannel, it carried out descending arrangement obtains
Figure 2011103858491100001DEST_PATH_IMAGE024
individual ; Then; Initialization; Introduce as iterative parameter; Make
Figure 2011103858491100001DEST_PATH_IMAGE030
, calculate subsequently:
(8)
Value; When ; With
Figure 2011103858491100001DEST_PATH_IMAGE036
; Otherwise; Then put
Figure 2011103858491100001DEST_PATH_IMAGE038
; And
Figure 2011103858491100001DEST_PATH_IMAGE040
; Continue
Figure 2011103858491100001DEST_PATH_IMAGE042
of statistical formula (8); And the like, till calculating all
Figure 2011103858491100001DEST_PATH_IMAGE044
; At last,
Figure 868984DEST_PATH_IMAGE044
distributed to corresponding subchannel.
CN2011103858491A 2011-11-29 2011-11-29 Multi-hop relay OFDM information transmission method facing to distributed wireless sensor network Pending CN102387114A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103684563A (en) * 2013-12-09 2014-03-26 复旦大学 Iteration multi-antenna transmission method and device under pinhole channel environment
CN104052571A (en) * 2013-03-13 2014-09-17 中国科学院大学 Dual-antenna wireless sensor network node for fire detection

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1719761A (en) * 2005-07-19 2006-01-11 电子科技大学 Communication method for distributed multi-input muti-output orthogonal frequency division multiplexing communication system
CN101515917A (en) * 2009-03-25 2009-08-26 东南大学 Multi-user wireless communication system based on both-way trunk and method thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1719761A (en) * 2005-07-19 2006-01-11 电子科技大学 Communication method for distributed multi-input muti-output orthogonal frequency division multiplexing communication system
CN101515917A (en) * 2009-03-25 2009-08-26 东南大学 Multi-user wireless communication system based on both-way trunk and method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
刘俊等: "基于注水算法的多跳MIMO-OFDM系统", 《中国科技论文在线》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104052571A (en) * 2013-03-13 2014-09-17 中国科学院大学 Dual-antenna wireless sensor network node for fire detection
CN103684563A (en) * 2013-12-09 2014-03-26 复旦大学 Iteration multi-antenna transmission method and device under pinhole channel environment
CN103684563B (en) * 2013-12-09 2017-02-15 复旦大学 Iteration multi-antenna transmission method and device under pinhole channel environment

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Application publication date: 20120321