CA2109211A1 - Process and arrangement for the differential modulation of signals in a multi-channel transmission system - Google Patents
Process and arrangement for the differential modulation of signals in a multi-channel transmission systemInfo
- Publication number
- CA2109211A1 CA2109211A1 CA002109211A CA2109211A CA2109211A1 CA 2109211 A1 CA2109211 A1 CA 2109211A1 CA 002109211 A CA002109211 A CA 002109211A CA 2109211 A CA2109211 A CA 2109211A CA 2109211 A1 CA2109211 A1 CA 2109211A1
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- CA
- Canada
- Prior art keywords
- sub
- data
- carriers
- multiplier
- carrier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
- H04L27/2602—Signal structure
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
- Mobile Radio Communication Systems (AREA)
- Transmitters (AREA)
- Radio Transmission System (AREA)
Abstract
The invention relates to a digital modulation process and an arrangement for a multi-channel transmission system in which the data flow is distributed over a plurality of sub-carriers lying close together in the frequency range. Neighbouring sub-carriers are interlinked in such a way that the data on two adjacent sub-carriers are transmitted in phase difference. If such a frequency-differential modulation is coupled to a prior art differential modulation in which data symbols on a sub-carrier following one another in time are transmitted in phase difference, a markedly better transmission quality is obtained in the signals in the radio channels.
Description
OCT 13 '~3 1~3:40 SPENCEæ,F~NK~CCHNEI~E~W~aH~ P.3.~1?
? ~109211 FILE, ~ McNDED
T-~T TRANSLATION
~0 ~2/20179 PCT/~1~9~/008~1 'e~ ~
D a~D ;~ANGE~ ~OR ~HE D~ u~N~rTA~ ~4I~UI~OM
oY ~ a~EL ~R~D8~I8~ Y8~
'rhe inv~n~ion x~ia~ to a digit;~ odulation me~ho~ and ar! arr~rlgç~e~}t ~or a ~nulti-~h~nnel tran~ is~io~ syste~
Whic~ d~a s~rea~ i~ d~t~cibut~d to a plurality o~
c:arriers ~at l~e~ adjac~nt tu one another in th~3 fr~uer~c:y ~m~in4 o m~ in ratltio~ i~ us~d, among ot:h~;rs, i~ th2 ~O~DM t~:tsda~
ort~sgç~nal ~r~ cy div~ n mult~pl~xin~ ~eth~d e~ployed in dis~i al radioO
~n ~ mul~l-chan~ aodula~ on ~et~ or digi1:a~ da~a ~an~is~ion, the data s~rea~ to be tra~s~nitted i~
di~ribut~d to a nu~er o~ sub-c:arEier~ ~or exampl~, sev~al .
hm~r~d1,, ~hich are 21dj~oe~ ~o one ano~:her in ~h~ f~eg~l3ncy do31~in, with ~h~ ~pe~:tra of t~a~ sub-carr~ ~rs po~3~3ib~ o ~erlappin~ Wit~ thi& ~ann~r of proceeding, ~ data rat~
tr~ itted in ~ach sub-carrier which i lower ~y order~; o~
? ~109211 FILE, ~ McNDED
T-~T TRANSLATION
~0 ~2/20179 PCT/~1~9~/008~1 'e~ ~
D a~D ;~ANGE~ ~OR ~HE D~ u~N~rTA~ ~4I~UI~OM
oY ~ a~EL ~R~D8~I8~ Y8~
'rhe inv~n~ion x~ia~ to a digit;~ odulation me~ho~ and ar! arr~rlgç~e~}t ~or a ~nulti-~h~nnel tran~ is~io~ syste~
Whic~ d~a s~rea~ i~ d~t~cibut~d to a plurality o~
c:arriers ~at l~e~ adjac~nt tu one another in th~3 fr~uer~c:y ~m~in4 o m~ in ratltio~ i~ us~d, among ot:h~;rs, i~ th2 ~O~DM t~:tsda~
ort~sgç~nal ~r~ cy div~ n mult~pl~xin~ ~eth~d e~ployed in dis~i al radioO
~n ~ mul~l-chan~ aodula~ on ~et~ or digi1:a~ da~a ~an~is~ion, the data s~rea~ to be tra~s~nitted i~
di~ribut~d to a nu~er o~ sub-c:arEier~ ~or exampl~, sev~al .
hm~r~d1,, ~hich are 21dj~oe~ ~o one ano~:her in ~h~ f~eg~l3ncy do31~in, with ~h~ ~pe~:tra of t~a~ sub-carr~ ~rs po~3~3ib~ o ~erlappin~ Wit~ thi& ~ann~r of proceeding, ~ data rat~
tr~ itted in ~ach sub-carrier which i lower ~y order~; o~
2 0 mag~aitud~ ~han th~ origlnal d~ rate so that th~ 83~01 OCT 13 'g:~ 10:4; SPENCET;~,FRf~NK&SC~ E'~ SH~, 2109211 P.4~17 ~.,~ ,., ~) 92~20~7~1 PCTJEP92/0084l , ~
duration is corr~pondir~gly lengthened~ ~hi~ h~ ~n `.! advant~ge30u~ eff2~ if e¢hoQs app~ar i~ the trans~ls~ion channel. ~y suitably ~ixing th~ nuT~ber c2 sub-c~arriers, a ..
lt~-~hannc~l modula~ion ~ethod ~an ~lways be de~ d so that t~ bol cluration 1~ long ~ompared tca the m~xim.lm ~cho delay ~ime o ~e expe~ted~
The ~ nf luena~ c~ e~hoe~ can be completely el ila~nated, ~or e~ple, in that the syml~ols are no~ nfi~itted in i~nedia ~ ~ucc~88loll but; I;ha~ ~ prol:ection period is jpravid~d 10 be~ween every ~o suc:c~ sive sy~ol~ which the echo~s of t~e ~ir~'c tr~mi~ted sym~ol die ou~.
m~ en~ine~ring c~f ~ ~aulki-~h~nnel ~o~ulation method ~3~ imol~a~ a aon~iguratlon, for ~xample, ~s a d~gital ~et~c~d, rhaps a~; a pr~gr~ in at l~ast one mic:roproce~sor with . lS: whlch the ~ra~it ~ n~ calc:ulated at ~e trans~i~ting ;:$ n~l in tha c~aplex base ban~ or at an in~rmediate freg~len~
thcd~ known ~ro~ the a~alcg technol~ hi$ tran~DIif ~ :
ig~al ~:z~ 'chen b~ put into thB carrier ~re~ncy po~ition.
.
o~rQs~orld~gly~ na~l is initially receive~ ~y t~e r6ac~iver in an ~ g ~ode, is then converted down to the a~ band or ~o ~n iI~termedia~e ~re~uency and is then : proc~d f~rther in a digital mod~.
~y ,i, ,, !
OCT 13 '93 10:41 ~ENOER,FRflNK&SCHrK IDEP/WF`JSHo P.5/17 . . .
t, 2 ~ O ~ 2 1 `" 110 ~2~2~ PC~ 2~00~
, ,j' The ~ulti-~hannel modulation signal is ~ompo~ed o~ time-~requency ~lot~ The time ~o~ are formed ~y ~e di~crete ~y~bol clo~k, the ixe~uen~y ~lot~ by the sub-aarrier ~ reguency ~pacing. rf m~a~ures ar~ taXen to c:ombat echc~23, s ~or xa~ple, the abov~-mentioned protection p~riod, the $n~1uQncQ o~ the radio ahannel in each time-~e~u~ncy ~o~ is mani~est ~n attenuation and a ph~e ~hift. A~tenuation and ph~ hi~t ar~ gener~lly ~ariable in tima ~nd fr~qu~ncy.
~;. Pre~ bly the known phase ~o~ula~ion is employed as ~he 0 ~odulatlon method::for a ~ub-carrie~ of the multi~ahannel signal. To this er~ he Y~riou5 data ~bols are ~epraduced on different phase sh~pes ~of ~he~ ~ans~it signal~ For . . .
da3l~0dulat~csn, ~h~ chann~ peci~io phase shi~t then acts as ~ an in~er~ere~ce value whl~h ~ust be a~pensat~ by mean~ of ,~ 15 su~able ~easures~ :
: Known methods are the di~erential de~odula~ion ~nd the iff~rential pr~coding. In ~he~e method, tho data are not trarumitt~d in t;:he p~as~ o~ a sym1~ol b~t in the phase ;., ai~re~enc~ o~ tvo ~u~ iYe æy~ol~. In a multi-ch~
'; 20 method, dif~erential de~odul~tion and precoding are pe~fo~med '~ s~p~rately in each ~ub-caxrier.
'`,J ~ ~ .
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~.i 2 1 ~ ~ 2 ~ ~ 23930 341 . ~ .
~ Differential precoding takes place in the transmitter ; (Figure la) and differential demodulation takes place in the receiver (Figure lb).
The multiplication of complex numbers corresponds to an addition of their phases, the formation of the conjugate complex number corresponds to the inversion of the sign of the phase.
The letter "D" in Figures la and lb identifies a delay by one symbol; the * symbol identifies the conjugate complex component.
Differential demodulation and precoding are based on the assumption that the channel specific phase shift does not change from one symbol to the next. In time variable radio channels, however, this assumption is frequently not met, particularly if multi-channel methods are involved with their .. , relatively long symbol duration. Transmission errors occur here even in the noise-free state.
~:
~ ; The principle that is a duplicate of time differential s~ modulation is frequency differential modulation. The frequency differential modulation is based on the assumptio~ that the channel specific phase shift from-one sub-carrier to the next does not change.~ The time differential modulation and the :
~ frequency differential modulation are described in "Philips .. . .
~esearch ~eports + SuppIements", No. 4, pages 91098 ~1973).
~` It is therefore the object of the invention to provide a modulation method and an arrangement for a multi-channel transmission system with which the transmission quality of the signals of unsteady radio channels is improved.
1:~
~1 2 1 0~211 23930-341 .~i This is accomplished by the characterizing features of patent claims 1 and 2. A further embodiment is de~ined in claim 3.
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~ - 4a -i OCT 1~ ~g3 10:42 SPENCER,FI~PNK~SCHr~IrlER,'Il~SH~ D, ,~17 ` -- 21092~1 1~0 9ZJ20179 PC~EP~OO~1 ~ odi~ents of the invention will now be described with re~erenc~ to 3chematic drawing ~i~ureC.
Figure 2 ~how~ co~pon~nts o~ an ~ml30dimen'c of an .~, arrange~ent at th~ transmitting end ~d an arr~ngement at the
duration is corr~pondir~gly lengthened~ ~hi~ h~ ~n `.! advant~ge30u~ eff2~ if e¢hoQs app~ar i~ the trans~ls~ion channel. ~y suitably ~ixing th~ nuT~ber c2 sub-c~arriers, a ..
lt~-~hannc~l modula~ion ~ethod ~an ~lways be de~ d so that t~ bol cluration 1~ long ~ompared tca the m~xim.lm ~cho delay ~ime o ~e expe~ted~
The ~ nf luena~ c~ e~hoe~ can be completely el ila~nated, ~or e~ple, in that the syml~ols are no~ nfi~itted in i~nedia ~ ~ucc~88loll but; I;ha~ ~ prol:ection period is jpravid~d 10 be~ween every ~o suc:c~ sive sy~ol~ which the echo~s of t~e ~ir~'c tr~mi~ted sym~ol die ou~.
m~ en~ine~ring c~f ~ ~aulki-~h~nnel ~o~ulation method ~3~ imol~a~ a aon~iguratlon, for ~xample, ~s a d~gital ~et~c~d, rhaps a~; a pr~gr~ in at l~ast one mic:roproce~sor with . lS: whlch the ~ra~it ~ n~ calc:ulated at ~e trans~i~ting ;:$ n~l in tha c~aplex base ban~ or at an in~rmediate freg~len~
thcd~ known ~ro~ the a~alcg technol~ hi$ tran~DIif ~ :
ig~al ~:z~ 'chen b~ put into thB carrier ~re~ncy po~ition.
.
o~rQs~orld~gly~ na~l is initially receive~ ~y t~e r6ac~iver in an ~ g ~ode, is then converted down to the a~ band or ~o ~n iI~termedia~e ~re~uency and is then : proc~d f~rther in a digital mod~.
~y ,i, ,, !
OCT 13 '93 10:41 ~ENOER,FRflNK&SCHrK IDEP/WF`JSHo P.5/17 . . .
t, 2 ~ O ~ 2 1 `" 110 ~2~2~ PC~ 2~00~
, ,j' The ~ulti-~hannel modulation signal is ~ompo~ed o~ time-~requency ~lot~ The time ~o~ are formed ~y ~e di~crete ~y~bol clo~k, the ixe~uen~y ~lot~ by the sub-aarrier ~ reguency ~pacing. rf m~a~ures ar~ taXen to c:ombat echc~23, s ~or xa~ple, the abov~-mentioned protection p~riod, the $n~1uQncQ o~ the radio ahannel in each time-~e~u~ncy ~o~ is mani~est ~n attenuation and a ph~e ~hift. A~tenuation and ph~ hi~t ar~ gener~lly ~ariable in tima ~nd fr~qu~ncy.
~;. Pre~ bly the known phase ~o~ula~ion is employed as ~he 0 ~odulatlon method::for a ~ub-carrie~ of the multi~ahannel signal. To this er~ he Y~riou5 data ~bols are ~epraduced on different phase sh~pes ~of ~he~ ~ans~it signal~ For . . .
da3l~0dulat~csn, ~h~ chann~ peci~io phase shi~t then acts as ~ an in~er~ere~ce value whl~h ~ust be a~pensat~ by mean~ of ,~ 15 su~able ~easures~ :
: Known methods are the di~erential de~odula~ion ~nd the iff~rential pr~coding. In ~he~e method, tho data are not trarumitt~d in t;:he p~as~ o~ a sym1~ol b~t in the phase ;., ai~re~enc~ o~ tvo ~u~ iYe æy~ol~. In a multi-ch~
'; 20 method, dif~erential de~odul~tion and precoding are pe~fo~med '~ s~p~rately in each ~ub-caxrier.
'`,J ~ ~ .
~1 .
~l -- 3 --~'1 ! i .~
~.i 2 1 ~ ~ 2 ~ ~ 23930 341 . ~ .
~ Differential precoding takes place in the transmitter ; (Figure la) and differential demodulation takes place in the receiver (Figure lb).
The multiplication of complex numbers corresponds to an addition of their phases, the formation of the conjugate complex number corresponds to the inversion of the sign of the phase.
The letter "D" in Figures la and lb identifies a delay by one symbol; the * symbol identifies the conjugate complex component.
Differential demodulation and precoding are based on the assumption that the channel specific phase shift does not change from one symbol to the next. In time variable radio channels, however, this assumption is frequently not met, particularly if multi-channel methods are involved with their .. , relatively long symbol duration. Transmission errors occur here even in the noise-free state.
~:
~ ; The principle that is a duplicate of time differential s~ modulation is frequency differential modulation. The frequency differential modulation is based on the assumptio~ that the channel specific phase shift from-one sub-carrier to the next does not change.~ The time differential modulation and the :
~ frequency differential modulation are described in "Philips .. . .
~esearch ~eports + SuppIements", No. 4, pages 91098 ~1973).
~` It is therefore the object of the invention to provide a modulation method and an arrangement for a multi-channel transmission system with which the transmission quality of the signals of unsteady radio channels is improved.
1:~
~1 2 1 0~211 23930-341 .~i This is accomplished by the characterizing features of patent claims 1 and 2. A further embodiment is de~ined in claim 3.
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~ - 4a -i OCT 1~ ~g3 10:42 SPENCER,FI~PNK~SCHr~IrlER,'Il~SH~ D, ,~17 ` -- 21092~1 1~0 9ZJ20179 PC~EP~OO~1 ~ odi~ents of the invention will now be described with re~erenc~ to 3chematic drawing ~i~ureC.
Figure 2 ~how~ co~pon~nts o~ an ~ml30dimen'c of an .~, arrange~ent at th~ transmitting end ~d an arr~ngement at the
3 5 r-c~iving ~nd, ~ach ha~ing several ~ carrier~i ..., k-l, k, l~tl, . . ~, inluding a mllltip~ ier at both the transmi~t~ng end and the ~eaeivin~ ~nd ~or linkirlg the d~ta af r~specti~e adjacent uib-aarrler~. ~n ~he tran~ ter, fo~ examp~e~ the ~u}tlplied data of #Ub-¢arrier~ k-l and k are ~ed to the ~10 ~ultiplier of sub~ arrier k+l and are multipl~ed with the ,j data or ~ carrier k~ t the rece~ving end, ~his ~ignal o~ ~ub-carr~e~ k~l is ~ultlplied with ~e aon~ug~te complex s~gnal o~ sub-carrier k.: This m~thod is a~lled fxequenay di~erenti~ odulation.
~ ~ Th~ ~hod r-al~;z~d~ with this arrange~ent Ls ~ased on the a~ou~ption ~hat the ~hannel ~peci~ic pba~e s~i~t does not ahAnge ~rom one au~-c~rier to the next. This a~aumption is imilar to th~ in the~known differential ~odul~tion, except ; that freguency inv~riance has taken th~ place o~ ~i~e ~2Q invarianc~. Howe~r r, particularly in multi-chanrt,el mo~ulatiorl m~thods, th~ ~:a~ts,r is fr~ntly mor~ likely ~o sxis~ ir~e the long ~;y~c~l du~tion corre~posld~; ~o fregu~ncy ~pacing ~n the ~ carrier~.
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~T 13 '~3 10:42 SPEI~CER~F~NK~SCHNEIl:;ER~ lSH~, P.8~17 ,,.~.
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~0 g2/20~.7S ~ EP~/008 i, In a ~u~t~er e~odiment according to Fig~lre 3, an a~range~nt ia 6hown at ~e ~rans~itter and rec:eiver ~n which éimely ;uaae~ e data ~ ; af a ~ a~rier a~; well a~
, dat~ ~ro~ ad~ac~nt ~ub-~arrier~ are linked t~gether. For 5 exa~ple, in sub~ a~er k~1 o~ ~e transmit~er, d~ta tha~ ~re transmit~ed in ~h~ pha~e di~rence o~ two su~c~e~siv~ d~ta ~;~bols are fed to a multiplier together with ~he multiplied da~ of sub-carriers k-l and k. In the receiver, t;his ~ultiplied complex~ signal of sub-carrier k+l i~ ltiplied 3 wîth t~e aon~ugat~ ~o~aplex s~gnal of ~ arrie~ ~. Together ;
h ~e a~n~ug~te o~plex ti~e-delayed ~ignal, ~hi~
i~z ~ultlpl~ed sl~n~l :ls ~h~n fed ~o a fu~hcr ~ul~lplie~. In ~: the ~tran~QLtter, ~he signa~ of the 3ub-~arriers are inltially di~f-ren~ially and :th2n ~requ~nc:y differentially 15 ~ pre~:oded wi~h ~his: doù~le differential modulation and are `'41` ~ ~
th-n de311odula~d ~n;~he~r ceiver, ~irst differentially and h~n f~quenc:y d~er~ntially. The dou~le di~erential :
~odul~tlon ~y al~so be per or~ned at t~e tran~itter a~d ~t ',3~ . ~ t;he rea~r ~ir~t by a frequenc:y differential ~od~lation and 20 ~h~n ~y a dif~eren~lal ~odulati~n., Compar~ld to th~ conventiona~ difr~r~ntial m~dul~t~ n and also comp~red to the fre~uon y diff~tr~n~ial ~o~ulat~on, th~
double di~ferential l~odulation o~er~ the de~isive advantage ~::
CICT 13 '93 10 43 SPENOE2~FRfWK~iSCH~EID~R~ Ho P.9~.7 ~t ,~ , ..
~ ' 2109211 1~0 9~ 0~1,7g ~ EPg:!~OOt~l li that it neithe~ re~uires the as~u:mption o~ ~ ti~e in~r~rianaenor of a ~reque~y ~nvarianae o~ ~e channel ~pecific: ph~e -, ~ift but app~ox~tes ~he ahannel our~e ~h~pe over ti~e and ~re~u~ncy by way o~ a~ plane~ In radio channel~, thi~
5 approxi~ation i~ clearly better than Em approxim~tion by way ;, o~ a pha~- curv~ tha~t i~ cons~ant ov~r tim~ and fr~ ncy, i, respectively.
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~ ~ Th~ ~hod r-al~;z~d~ with this arrange~ent Ls ~ased on the a~ou~ption ~hat the ~hannel ~peci~ic pba~e s~i~t does not ahAnge ~rom one au~-c~rier to the next. This a~aumption is imilar to th~ in the~known differential ~odul~tion, except ; that freguency inv~riance has taken th~ place o~ ~i~e ~2Q invarianc~. Howe~r r, particularly in multi-chanrt,el mo~ulatiorl m~thods, th~ ~:a~ts,r is fr~ntly mor~ likely ~o sxis~ ir~e the long ~;y~c~l du~tion corre~posld~; ~o fregu~ncy ~pacing ~n the ~ carrier~.
: ~ :
.
~T 13 '~3 10:42 SPEI~CER~F~NK~SCHNEIl:;ER~ lSH~, P.8~17 ,,.~.
.i. .
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~0 g2/20~.7S ~ EP~/008 i, In a ~u~t~er e~odiment according to Fig~lre 3, an a~range~nt ia 6hown at ~e ~rans~itter and rec:eiver ~n which éimely ;uaae~ e data ~ ; af a ~ a~rier a~; well a~
, dat~ ~ro~ ad~ac~nt ~ub-~arrier~ are linked t~gether. For 5 exa~ple, in sub~ a~er k~1 o~ ~e transmit~er, d~ta tha~ ~re transmit~ed in ~h~ pha~e di~rence o~ two su~c~e~siv~ d~ta ~;~bols are fed to a multiplier together with ~he multiplied da~ of sub-carriers k-l and k. In the receiver, t;his ~ultiplied complex~ signal of sub-carrier k+l i~ ltiplied 3 wîth t~e aon~ugat~ ~o~aplex s~gnal of ~ arrie~ ~. Together ;
h ~e a~n~ug~te o~plex ti~e-delayed ~ignal, ~hi~
i~z ~ultlpl~ed sl~n~l :ls ~h~n fed ~o a fu~hcr ~ul~lplie~. In ~: the ~tran~QLtter, ~he signa~ of the 3ub-~arriers are inltially di~f-ren~ially and :th2n ~requ~nc:y differentially 15 ~ pre~:oded wi~h ~his: doù~le differential modulation and are `'41` ~ ~
th-n de311odula~d ~n;~he~r ceiver, ~irst differentially and h~n f~quenc:y d~er~ntially. The dou~le di~erential :
~odul~tlon ~y al~so be per or~ned at t~e tran~itter a~d ~t ',3~ . ~ t;he rea~r ~ir~t by a frequenc:y differential ~od~lation and 20 ~h~n ~y a dif~eren~lal ~odulati~n., Compar~ld to th~ conventiona~ difr~r~ntial m~dul~t~ n and also comp~red to the fre~uon y diff~tr~n~ial ~o~ulat~on, th~
double di~ferential l~odulation o~er~ the de~isive advantage ~::
CICT 13 '93 10 43 SPENOE2~FRfWK~iSCH~EID~R~ Ho P.9~.7 ~t ,~ , ..
~ ' 2109211 1~0 9~ 0~1,7g ~ EPg:!~OOt~l li that it neithe~ re~uires the as~u:mption o~ ~ ti~e in~r~rianaenor of a ~reque~y ~nvarianae o~ ~e channel ~pecific: ph~e -, ~ift but app~ox~tes ~he ahannel our~e ~h~pe over ti~e and ~re~u~ncy by way o~ a~ plane~ In radio channel~, thi~
5 approxi~ation i~ clearly better than Em approxim~tion by way ;, o~ a pha~- curv~ tha~t i~ cons~ant ov~r tim~ and fr~ ncy, i, respectively.
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Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A multi-channel modulation method wherein the data stream is distributed to a plurality of sub-carriers which are adjacent to one another in the frequency domain, characterized in that the data are transmitted in the phase difference of adjacent sub-carriers and in the phase difference of timely successive data symbols in the respective sub-carrier.
2. A receiver and transmitter arrangement for a multi-channel modulation method according to claim 1, characterized in that at the receiving end and at the transmitting end each sub-carrier includes a multiplier which links the data of two timely successive data symbols in the respective sub-carrier and a further multiplier links the data of adjacent sub-carriers.
3. A receiver-and transmitter arrangement for a multi-channel modulation method according to claim 1, characterized in that at the receiving end and at the transmitting end each sub-carrier includes a multiplier which links the data of adjacent sub-carriers and a further multiplier links the data of two timely successive data symbols in the respective sub-carrier.
4. A receiver and transmitter arrangement for a multi-channel modulation method according to claim 2, characterized in that at the receiving end and at the transmitting end each sub-carrier includes a multiplier which links the data of two timely successive data symbols in the respective sub-carrier and said multiplier is followed by a further multiplier which links the data of adjacent sub-carriers.
5. A receiver and transmitter arrangement for a multi-channel modulation method according to claim 2, characterized in that at the receiving end and at the transmitting end each sub-carrier includes a multiplier which links the data of adjacent sub-carriers and said multiplier is followed by a further multiplier which links the data of two timely successive data symbols in the respective sub-carrier.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE4114274A DE4114274A1 (en) | 1991-05-02 | 1991-05-02 | METHOD AND ARRANGEMENT FOR DIFFERENTIAL MODULATION OF SIGNALS IN A MULTI-CHANNEL TRANSMISSION SYSTEM |
DEP4114274.8 | 1991-05-02 | ||
PCT/EP1992/000841 WO1992020179A1 (en) | 1991-05-02 | 1992-04-14 | Process and arrangement for the differential modulation of signals in a multi-channel transmission system |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2109211A1 true CA2109211A1 (en) | 1992-11-03 |
Family
ID=6430783
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002109211A Abandoned CA2109211A1 (en) | 1991-05-02 | 1992-04-14 | Process and arrangement for the differential modulation of signals in a multi-channel transmission system |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP0589895A1 (en) |
JP (1) | JPH06507053A (en) |
AU (1) | AU652052B2 (en) |
CA (1) | CA2109211A1 (en) |
DE (1) | DE4114274A1 (en) |
FI (1) | FI934830A0 (en) |
WO (1) | WO1992020179A1 (en) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7239666B1 (en) | 1994-09-09 | 2007-07-03 | Sony Corporation | Communication system |
JP3577754B2 (en) * | 1994-09-09 | 2004-10-13 | ソニー株式会社 | Communication method and device |
US5649297A (en) * | 1994-10-21 | 1997-07-15 | Seiko Communications Holding N.V. | Transmitting digital data using multiple subcarriers |
FI99252C (en) * | 1995-07-03 | 1997-12-29 | Nokia Mobile Phones Ltd | Combined radio signal modulation and multi-use method |
DE19638654A1 (en) * | 1996-09-20 | 1998-03-26 | Siemens Ag | Digital message transmission method |
DE19719762A1 (en) * | 1997-05-10 | 1998-11-12 | Bosch Gmbh Robert | Process for the transmission of data, as well as transmitter and receiver |
EP0991237A1 (en) * | 1998-09-30 | 2000-04-05 | TELEFONAKTIEBOLAGET L M ERICSSON (publ) | Multicarrier communication method with time-frequency differential encoding |
GB2373148A (en) * | 2001-02-01 | 2002-09-11 | Roke Manor Research | Intra symbol differential modulation of a multi-carrier signal |
GB2383726A (en) * | 2001-12-31 | 2003-07-02 | Calum Ian Bruce Gorton | Dual frequency radian differential information transfer |
US8361045B2 (en) † | 2006-03-10 | 2013-01-29 | Kimberly-Clark Worldwide, Inc. | Apparatus and method for manufacturing several distinct disposable absorbent articles on a single machine |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4029478C2 (en) * | 1989-09-28 | 1995-08-03 | Siemens Ag | Method for the transmission of data in a bus system |
DE3935911A1 (en) * | 1989-10-27 | 1991-05-02 | Deutsche Forsch Luft Raumfahrt | METHOD FOR RECEIVING BIT DETECTION OF DIFFERENTIALLY CODED BINARY OR QUATERIAL PSK SIGNALS IN DIFFERENTIALLY COHERENT DEMODULATION |
-
1991
- 1991-05-02 DE DE4114274A patent/DE4114274A1/en not_active Withdrawn
-
1992
- 1992-04-14 WO PCT/EP1992/000841 patent/WO1992020179A1/en not_active Application Discontinuation
- 1992-04-14 EP EP92908599A patent/EP0589895A1/en not_active Ceased
- 1992-04-14 AU AU16430/92A patent/AU652052B2/en not_active Withdrawn - After Issue
- 1992-04-14 JP JP4507989A patent/JPH06507053A/en active Pending
- 1992-04-14 CA CA002109211A patent/CA2109211A1/en not_active Abandoned
-
1993
- 1993-11-01 FI FI934830A patent/FI934830A0/en not_active Application Discontinuation
Also Published As
Publication number | Publication date |
---|---|
EP0589895A1 (en) | 1994-04-06 |
DE4114274A1 (en) | 1992-11-05 |
AU1643092A (en) | 1992-12-21 |
JPH06507053A (en) | 1994-08-04 |
WO1992020179A1 (en) | 1992-11-12 |
FI934830A (en) | 1993-11-01 |
FI934830A0 (en) | 1993-11-01 |
AU652052B2 (en) | 1994-08-11 |
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