CA2419750A1 - Method for localising direction and localisation arrangement - Google Patents

Abstract

The invention relates to a method for localising sources of electromagnetic or acoustic signals in relation to a sensor arrangement (1a to 1c) with at leas t two electrical outputs. The two transmission functions, which are dependent on the direction of incidence, are different between the acoustic signals that are incident on the sensor arrangement (1a to 1c) on the input side and the electrical output signals. According to the invention, the quotient (7I to 7II) of the output signals is formed and the result is then correlated with the previously determined quotient function (11).

Description

...
l~'ETHOD FCR LC3CALISING DIRECTION AND
L4CAL~SAT~ON' A,RRAT.~TGEfMENT
The present :i.n~rex~t~.oxa re:l.ates to a method for di:rectianal.lxr locating a source of electromagnetic ~or ac~:ustic signals according tv the precharacterizing c1 ause of cla:~m 2 anal to an arrangement for this ac~~ording ~to the pre~wharactervzing clause of claim Th~s insights leading to t~::e present invention Were acquired from needs re~.a~:ixzg to the directional.
1 (;
lo~Vation of acoustic sources. Accordingly! the present de:~cription of the ~.rzrrentia:-: will also be concerned mo,5tly with the directional location of acoustic so~_zrces. Nezrerthe~.ess; a person skilled. i.n the art readily appreciates that t~xe present invention is entirely suitable fa~ ~ae~.ng extended to t::~e .ocating of el,~ctrr~magnetic sigr;.a? sources. The question as to wh:~cl~. ks.nd of sour~.xes are to be located only affects th~~ kind c~f sensors used according to the: i.n~~ention.
=n the special case of ~kacat~.ng acc-austic signal soj.zrces, the sensor arrangement is an arrangement of 2:~ microphones, whereas tnrhen locating eiectromagne~~ic sources 3.t i.s an zzrrangemen. of antenna s followed by anj~enna boosters.
For the lac:ating of sucxz sources, l n part ic:ular in an en~,~ironmerzt an which a :chamber c~f sources rare active at the same time, xarocedurea whi{~~z are rr;athematicallv complex or demand subst.ant.ia:L equipment are presently known. If in th:~s ease .less equipment is used by reducing the number of sensors provided, the mathematical c.omplex~..ty relating to source--locating discrimination wil:. ixz turn increase. rat- locating a~
acoustic smgnal sources, t~ze aseextainment of phase differences between acoustic ~>ignals simultaneously incident an the micro~hnrles c,f the microt~hone WU 00/6$703 ~"C~lCH00100430 ar-rangemer~t w~._~1 bc~ taker aa,~ a basis h~:re by way of a}>ample .
It: is an abject a~ t~z~: present inverztian to propose a d~_x~ectional lacating method arzd a corresponding as°rangernent, by x~~.eanu of ~ahir:~~z the demands and requiremexzts r,-~enti.~.;ne~:d are d:=.~as:t.ica~.~.y reduced.
Taking a ~:nethod of take kirxr~ mc;ntianed at the beginning a:a a basis, this ~..:s ~.ch~.eveca by irnpleznent.ing it in the way specified by the c.ha~°ac:t.:rizing clause of claim 1.
I:~ a lens or ar. rarxgemez:t wi ~h at least t~wa electrical outputs is provi.s:~e~d, ~~r~_~h different transmission cr?aracter:~stic~s, ~.rteams :~f th.e depex~zde:~ce of the e:lectrica:L output :~ic:~z~zals nr tie r;~irectic~:~ of incidence of the input sigrla.ls, be~.nc~ effective between the electromagnet z. r: or aco:.zrt3.r.. ~.nput and t.h~~ at least two e7.ectrica:l outpLxts ;mentianeci, in the fo.rxc~ of reception 1'obes, :~i.. has beerz ~.~bsez--;rec~ t2-zat, by~ farming the quoti ent for signals wh:zch x:wpresent the output signals mentioned, a quoti.~-~nt funr~t .on whacxz i.s wnambiguous for a locating- angle c; f: a source .end is independent of the signal level. :is formed. t~:ansequenr_7_~>, ~.xx tine minimal configuration of the prot::edure ~rx~apased, a locating angle is unambiguously ascertained, and it is this procedure which prouide~; th~~ basis for ascertaining two locating angles pc;:~ so3~ree arid tronsequently spatially f~.nding out the scFurce loc:at.ion uxzarc~bicruous:ly in the form of a locating b~ar~l a.~dor, when: there are a number cf sources active a.t the ~>ame time, lac~at~.ng them at least wit.hi.rz the one locat.ix:g angle mentioned. As Mtill to bc~ explaarze:~., the quotit-ant. for;ning mentioned cirectly prod.~aces fcfr the sau2ce location a lacatir_g cone, the aperture angle owhich is ascertained as a Locating c;oardz.nate.

wo aa~s$~os ~cTtcHOO~oo~so ._ ~5 ._ Unambiguous directican~~. :l.oc~-~ti.on of a source, i , e.
collating of a locating bean- for t4~e source, becomes possible by eva2uat~,r~g at "a. east thA ee of the quotients me:ntiorxed, for whic::h purpose, as implemented in a preferred em'oodiment, a~u iea~t three of Fhe electrical outputs are praYrided, ~:.ssi.gned to which are respectively ci.a.ffere~nt traxxsfer functioxxs of the afaremen~.ioned kind, i.e. :i.n the form of different receiving characteristics.
'1f the procedure x~zwv~.ous~,~- ciisc,ussed .used in an environment with on.l~ a. sixogle active signal source, said source :i.loc~a.ted. '1f, however, a number of signal sour. ces are ac:.? we a;: a:.he same time, an actual sp=ectrum of loo atirzc~ a ngles ? s produced, ar.d a single me:asure:nent does nn'-. im<.mrcsediat.e::.y reveal how many sources are active rind from, c~h~.c~z lcar:atiax~al direction.
Fc>r this purpose, i. t ~.s proposed ira a fur then preferred eniaodiment that the ~yat~.er~~ yormirxg mez~tior~ed is performed at several. staggered times and t he quotient rE.>sults are used to create rz ~xiatogr-axn fu»ction, which ins corre:lat.ed ~~:~th who: previously determined c~:mtient.!d.rection--of--inrv~.c~ex~.cc: dependencies and used to ascertain the locationa:i_ direction of: the at least oxm source .
This procedure is pre x.erably uw.ed both far implementing the procedure accarc.~.~.xzg to t~.he :i.n~;ention w~i~:h at least two of the outputs rc~entiar~ed and for implementing it with at least three r,f ti:e antpu~.:s me:~tio:~ed.
In the proposed h:~~itagra:n ~.~nc~ticn, e~.ect~romagneti c or acoustic signa~.s gerxeA~ated i;y sources which are acti ve for some tune result iry the same c.~-aotient values, which is reflected by these ~,ralues be.ir~g accumulated ir: the WO 00/6$703 PCT/CH00100430 _. ~ _ histogram funct:~on set~- up. tnzhen correlated with the pxevious3.y determined quotiexAt%direction-of-incidence dependence _nerztione;~~, these: accumulated values lead directly t:.o ascerta~.A~~.~nexzt of the respective at least one: locating angle o.f t~3e s~.gr~al sources actitre in the fie~.d.
Ir. a furtrzer preferred embodir;:er;t, the output signals of the sensor arrarvgemerzts ziiemtirar~ed are eTraluated in tf~e frec~,~ency cL:3rna:i.::. Considering that the tx~ansmiss~.on char aci::e:y°istiGS mentioned change with the signal frequency a:n~.y within the rol:Loi.f range, it fc>llows that ~-he effec~w c~f the frequency will be eliminated when forrn~.n.g t~_e quor~i.wz~t, i n particular whenever the :~elect:.ed tz~ansmissiori characteristics have the same rolloff behavior. Tazerefore, the sictnal eiraluatiorz in the fi:~equene:~r domain not only makes it possible to set u~a t:e h~.s;:.c~gram mentioned from time-st:aggered measurements, ~:zut: also from tze spectral q~notient results sirtult.aneau:s7.y ascerta~npd in the fx:equency domain.
Tz-ansznissiort charact;~~-istics assigned to the respective electrical outputs wh~.ch differ merely by a solid-arzgle phase shift, i.e. that "look" in a different direction bmt are otherwise zderzt:ica.i., are preferably chosen.
A:x arrangement of the aforez.zentioned kind according to the invention is distiny:.xi.shed accordirzg to the characterizinc.~ c~.~~~a5w of c:;.aAm ~, rnth preferred embodiments according t~; a..La3.ms , to 1C} . The method according to th~~ nventi.on r.zrzd the: arrangement ac~carding to the ~.nw~enti.or; are suitable i.n particular also for the locatx.rzg of acoustic sources and, on aac:ount: o~: trze ~.ower requireFr..exat for equipment and 3 PCTdC~I00/00430 coarputing powex, :~.rl ~a~Wiculax for implementation in t.h~~: Case Of hearing deV it~es .
They invention is :~u:~sequently explained by way of example on the basis of fi.gur.~es, it which:
figures 1a, 1b show transmission charac~,::eristics used in preference az:c:c.~xdir~g ø~c. the invention for the :locating c;f acoustic sozrces i~~ raze case of t.wn suba~~.crcphone s.z-rangements that are provided, ~n a minimal configuration.;
figure 7.c. shows th~~ common :spat- a1 oxient.ation of the transmiss ~.;azz c'.=-zaractex~i.st:~.cs for submicrcaphone arr:~r_gerr~erats av shown in f figures a. a arid 1b ;
figure l shows, plotted ag~a inst the one solid angle cp, as shown vzz f i.gt.r,_=.s la to -~b, the absolute value of the respective transmission charactex-istic; and of the q~uotierzt function ;
figure 3 shawl, p'.otted agwinsc, the sc~lia angle tp, enlarged, the quotient fuaz~~tion as shown in f.igu~w 2 c.o expaairt the correlation of ACTUAL
va7.ue rneaszx:~em~ez~~. arW prevWously known dependence between ;~~~~tient and angle cp;
figure ~ shows as axz exams3le a hi.stog~:a;z; functior_, ormed on the l~asAs of yuot-ient results ascertained at stab;gored :imes:
figure 5 snows, on the basis of a simp'.ified signal-flow~'func:ti;ana~~.-bl.t~ck diagram, a. locating arrangements designed a~cording to the wo oo~ss~o;~ ~cT,cxaoroo~3o invention aid oper.~t~.ng on the basis of the method ;~c:cording to the i.nvexzti on for acoustic signa:L Sources, in a preferred embodizr~en't ;
figure 6a shows the :~ccating positiora zor a signal :~o~zr~:e, as ascertained by the procedure according to the invention or arrangement ;ae:cording to the irzventican in the minimal configuration;
figure 6b shows twr, locating beams, as ascertained in a development of the inyrentian , arid figure 6c shows the a certa:i.nment of the one locating beazr., as asz:ertaixzed in a further preferred embodiment of the 3.nvent i,on .
T:~e procer3urc ae.carding te> the .~.rz:rentwon is to be pi:esented by means of figures ~. to ~ wit.ha~zt claim to scientific e:k.actitzzde, cr... the basis of simple ti:;~nsmisszon criarac:teri st.c~:, correspond.~.ng to first-oa~der cardiai ds . This c~.eax~, :pimple procedure d~ascribed :oelow in;~tructs a persar. ski~.led in the art how according to t~ze invention it is possible even on the basis of suite ec>mple:x. transfer functions for one o:~ more acoustic sozarr..es to be located acr~ordiz~.g to the i_rmention.
A first submicrophone arrarzc~eznent - genes a1J_y a sensor a:rra.ngement - of ca znic.raphore arrangezzsent or sensor arrangement p:~avidecz is assumed to haire the three-dimensional transr~i.ssion ~~harar.t.eristia represented tv~o-dirnens:iona~:ly in figure 1%~ as the: t:ransznissi on. or a:rplificatian chars=vteristic c;f signa~.s ix=ovdent on it with respects to di:~-ertion cp.

WC~ OOJ68'~03 PC~/CH00/00~430 '7 Ir: a representation analogous to ~.~igure wa, figure 1b sr;aws the tr_ansmiss:i_an characteristic of a second s~~n.sar arr angement, which i:~ assuzrced to be the mirror image with respect to thEa axis 7t/Z; ~'~/2 of the tx-ansmissi.r~n characteristic: of the first sensor axvrangemeru::. The t.ransmiss:~on characteristic as shown irz figure la is denoted by ~~;~, that as Shawn in figure 1b by cx. Figure lc shows the transmission eAzaraeteri:~ties e~ and c~ simultaneously, as they pi°esent themselves with '!°espert to the transfer functions orz a sensor arranger~ez~t with ceorrespondimgly two subsensar arrangements G:nd two electrical outputs.
As rnentianed, for locating acoustic sources, the arrangements are mic;rc~phane arrangements.
In figure ~, the abso~_ute valzxe cf the transmission c~~.aracter~.st:ics> c;,~ and c~, i;~ shorn in d~, plotted against the angle a:~.is cp as shown i n figures 1.a to 1c.
IL unitary signals are inc.dent an the two subsensor arrangements, t'.~:e traxnsmission r.hax-acteristics rf~presented it figzzres ~.a and 1b sir~~ultaneously c~:~rrespond trz the resper.a_.:~.ve signal wa.loe s on the output side of the sensor ax:range:t~ent be:i.ng considered.
A~~carding to the inventa.on, the absolute._..~a;ue quotient is then formed from these tv~a output sig na 1 values, vi:~~ich are l~.kewise denoted by c~ a:~ld c~, namely ~Crr~
Czll Ttais quotient farming ~~roduces the function Q
qualitat.iwely represented a.n figure 2 ~~y dash-dotted lines, with a pole at. ~ = r. .gin figure ~i, the quctient function ~ (c~) is p~' ~tte.d once again between. cp _. 0 and cp ~r~lG 00/68'03 ~~'~/CH00/00~30 _ g _ It. should be noted that, wrzezz farming the quotient Q, wh.ch for reasons of claritx~ :~zas first been explained or: the basis of unitary signals, the respective absolute va~.ues of the input signals cancel out by dl.visian, se that the angle dependence shown in figure 3 applies to arbitrary sigx~.a~.s incident. at ~ø on the SE?nSar arT.'cTT'xgeICtent .
I:f this function i:7 L:~en measured and wtored and, as schematically represented irl fi.gura 3, the irzstantaneaus quotient fur<c~:.ion QzF,;~ is farmed fro: an instantaneously incident signal TNS, again represented in dB, the dB value found c:an be correlated with the sf~ored quotient function Q (~~ , ~. . e. it c; an be entE=red w:i_th the found qzzatie:~t ~ralue into the previously stared funr_t.ian or depende nce Q (t~j : r_-he locating direction cpx~s of the irstanø~a~eously incident. acoustic s ign.al is ascertairz~:d, readily inferred franc cc>r.~:~ideratiar~ aF figure 3 and, fnr_ example, figures 1a and ~_b, the quoti~,nt function Q (t~? is unambigua~as froze G tr.~ x.80"', though only in the t~;~o-dimensional seswtional lane through Whe spatial transfer functions represented ir: figures 1° and 1b. A
locating angle ~ whic:~z corresponds to a locating cone e:rtered by dash-dotted lizAes in f igura la for the a;~erture angle t~ dep.:~.cted there is found.
If it, is wished t.o perform Location sznam~b?.guously, at least three of the subsensor arrangements mentioned are to be pro~Ticled; an d :~a~-respanding-Y;.y a sensor axrangemexzt with three outs>uts. ~'armirc-~ the quotient ire the way describe;~, and the correlation with the respectively pre-recorded dependen.ci.es Q (cp) , takes place in pairs an two, pre.~erably three, c>f the three output signals of Y.:he arranger~;er~a.

wo oa~s~~o~ ~cTrcHOO/oo~30 _~_ Although the locating ixiforwation ascertained so far reveals that, at the present instant, arl acoustic signal [lacunas from t:he locating d~.rectiar_. mentioned, whether this is establi>:~h.ed for t~~,To subsersar arrangement.a corresponding tr.~ a locat~.nc~ cane or for mare than two sensor arrangements spatial.l.~J by means of two or one locating beam, this only reveals that, at the present instant, an acoustic signal is incident Exam the direction mentioned. Consequently, a located acoustic signal source is ac:t~.ve at the present instant.
However, to obtain informat~.ar~ an t<ze location of an acoustic source active aver an extended peri.ad of time a~: distinct from ~>tachasti{awly distributEd acou~>tic signals incident from d:~_fferent directions, the pa acedure then fal7_awed in prii;c.ipl.e is to observe from which ~ oc;~.t~.ng dir~:~tion there is an accu.mulatian of 'incident signa~.s r~~.rpx the t~.me period, aJ~3.awing the caxlclusion that an acoustic signal saurt:~e is located there .
Fc~r this purpasE~, thp q:.:atient Q~;,;w mexztianed is repeatedly formed from the output signals and used to form a hiatagram, _as shown toy way of example in figure 4.. For this purpose; the frequencies are recorded specific to quotient values ;as show:. in figure 4 in d~3? . Figure 4 shaTVes in ta::is resper:t an example of a histogram recorded vn. this wayf writh the fre~.~.ency n of quotient va:~.ues Thai aC:~'larrE:f.~. The inference is that, according to the accurnu.r.at:ion at about ~-3 ~ dB and __;?~ dB as shown ixf figure 3, an acoustic source is active in the direct~..c->n c~ ~ w5' and one a~.:: cp = 35°.

wo oo/ss~os ~o~~cxoo~oo~~o Th.e proposed procedure is z.n this case eminently suitable far ixnplementatian in the frequency domain.
If it is 3.:aken into cc~nsidea-ation irz this respect that th.e transmission c~zaracteristics irx each case change f~wquency-dependently in a similar manner on account of the: frequency rolloff ., as s~.iawn for example in figures la, and 1b, it is evident what the quotient function mentioned is frequency.-independent, Canseq-gently, the output signals of the s~:nsar. arrangement can be converted consecuta.~re:~.y -:several times into the frequency domain. arzd the qyotient forming mentioned, which carztains the same d~,rectiona~. znforxnation independent of f.rec~uency, can be performed for a selected number of spectral azr~p~.? rude ~xal.ues in the frequency spectrum.
~nl~_th a number N of subset<sow arrangements, in particular- microphone arrangezc:ex~ ts, it. is possible by the proposed method to ir~ca~~e a possibl~Y substantially lezrger number M of signa:t. sources, iz: particular acoustic signal sources. '1f .~.r: this case mere than two s;zbsensor arrangements are u:~ed, there ~is a passibili_ty o~:= carrying out unam~~,guous spatial location:. It is for example also E~.;ident from the distribution from f:i.gure 4 that, in the local a.ng angle range between 110°
and 130", it is high~.y pw~obable that trno or more appro~i.mately identvcal sources are a,~.tz~Ie:.
In figure ~, a locating axwax~gement operating by the method ac~~ording to the invention is represented on the b;ais of a si.mp~lrified :~~.gnal--f l owlf.unctional--block diagram using the examp~.e of a locating arrangement for acoustic uignals. Lt is ~>ui4able in? particular also f ~r use on a hearing device .

WO 00/68703 ~°CTrCH001009'30 Th~s arrangement according to the irwention comprises a rnivrophane arrangement ~. with at .east two submicrophone arrangements 1,.: as shown preferably with three submicrophone arrangements ';~b - 1c, which are each led to corresponding ou=puts A1Q to AyC. The three submicrophone arrangements xzave different transmission characteristics, for examp:Le correspondingly first-order cardiaids pointing irs different diree:tions, which is implemented for example and by preference by the submicrophane arraxa.gements being set up with two microphoraes of which the outputs are co~xpled to each other by the °' delay and add" technique . Bar providing the three submicrophorze arra.x~gemerLts. a third cardioid ~.s created, making it possa.b:le far two or three quotients to be four°ed at thcJ same time arsd as still to be explained. Coaasc~quentl:;r, two locating cones as shown in f.z.c~ure 6b or three locatizzg cones as shown in ~~.gure 6c are ascertained. °~~it:n t:w~a locating cores, in each case a source is still ambiguously 'orated, with three it is unambiguously ~.o~:at.ed.
Ir.. a preferred embcsdiment , thf. outpt:t s=.gnats AXx are COZIVerted into the frequency domain at time-damain/frequency--dor~;ai.n ~~onvert.er units FFT 3a to 3c.
The outputs of the t..ime--domain/frequency-domain coxzverter units 3a t.o 3c are operatively connected in pG;irs, f.or example as represented in each ease via a~ssolute~-value forming a nits to x~'~;.merator or dc~nominatob inputs rif three quotient-forming units 71 to 7lir. The outputs of ~he qs~otient-forming units 7r to 7m1 are operativelx~ connected to an eval.uat~.on unit 9, at. which, as explained, in particular the histograms are formed. In ox~d~.~ to it~plement the c:or=elation of the found q~~otient-:,~alue distr~.b~~tio:. with the q~zotientl3.ocating-ax:gle dependence, the dependencies g rip, ) to ~ (cp~~ are addition 'ally fed to ~.he evaluat:ion wo oo~6e~os ~cT,~cHOa~oo.~~o "' .l. G "' uns.t 9, as schematically represented iri figure 5.
These dependencies were measured or calculated beforehand on the basis of the sensor arrangement 1 provided in the given case amd are stored, i>~ schematic farm, in the funetion memory unit ~.3.. ~rz this case, cpl to cp3 denote the lao.a.ting core apertuw-e a.rgles as shown in figures 6a to 6c. &~r appropriate conversion in the evaluation unit 9, i.e. evaluat.ion of the histogram distribution and assigrrrsent of its peak values to the corresponding locating angles> t~~ to cp~f th.erx appropriate conversion according to t~-.e desired locating coordinates, the number of detected acoustic: sources M
with their lacatin.g angles are output un the output side of the evaluation uz;it '!'he proposed procedjare is eminently su_i.t.able for implementation i.n xzearing :~eLr~.ces and ~::ar~ form the basis for directing the dire<::tional c haracteristic of a hearing device to deter:ted saurc:es, or ... f f these are defined or found to be sour~:es of interference - far setting up a high attenuaticin of the transmission characteristic in the locat:~r:g direMtion mentioned.
In principle, all known m~~orophones or sensors and their combinations, havin:~ different transmission characteristics as required :i.n the aperationa.l position and as required with respect to the direction of incidence c~ of irmidezxt acoustit~ signals, can be used as submierophone arrangements or subsensor arrangements.
However, especially for implerne:Atation w~ii.ch is simple anal easily monitored, it is proposed to use identical subsensor arrangements, the transmission cb.aracteristics of. whic.hl t=.;re indeed ~.T,~exatical but wo oo~~s~o3 ~cT~cHOO~oo~~o sp<~tially directed d:i~~ere~a:ly with respect. to axial al l gnment ( in figure i.~. corxes pondir~a to t~ = 0 ) .
With the procedure ~.ccording to ~.he inventior_ it is possible vaithout detexmvninc3 signal phases or signal time delays and ~nrithc°at ~asimg Cor respand.ingly complex lo~~arithrnatian of r~omplex variables to locate signal sources in an exceedingly simple manner by quotient forming and subsequent s~.~np2e evaluation in the em,,tironment, in par~.icular acoustic so:~rces in the acoustic en.v~.ranmert .

Claims (10)

Claims:

1. A method for directionally locating a source of electromagnetic or acoustic signals with respect to a sensor arrangement with at least two electrical outputs, the transfer functions, dependent on the direction of incidence, between acoustic signals incident on the input side of the sensor arrangement and electrical output signals at the two electrical outputs being different, characterized in that a quotient (Q INS) is formed from signals which represent the output signals of the sensor arrangement and at least one locating direction of the source is determined from correlation of the quotient result with the previously determined dependence of the quotient (Q(.phi.)) on the direction of incidence (.phi.).

2. The method as claimed in claim 1, characterized in that the sensor arrangement has at least three of the outputs and the quotient forming and correlation is performed on signals which are representative of the electrical signals at at least two, preferably at three, pairs of the at least three electrical outputs.

3. The method as claimed in either of claims 1 and 2, characterized it that the quotient forming is performed several times and the results are used to create a histogram function, which is correlated with the previously determined quotient/direction-of-incidence dependence and used to ascertain the locational direction of the at least one source.

4. The method as claimed in one of claims 1 to 3, characterized in that the signals at the output of the sensor arrangement are fed to the quotient forming in the frequency domain.

5. The method as claimed in one of claims 1 to 4, characterized in that transmission characteristics which define different spatial reference angles, but in this respect are at least approximately identical, are created.

6. An arrangement for directionally locating sources of electromagnetic or acoustic signals, with a sensor arrangement (1) with at least two electrical outputs (A xy), the sensor arrangement having different transfer functions, with respect to the direction of incidence of the signals, between incident electromagnetic or acoustic signals and the outputs (A xy), characterized in that at least one quotient-forming unit (7) is operatively connected to the at least two outputs (A xy) of the sensor arrangement (1), which unit is operatively connected an the output side to at least one input of an evaluation unit (9), at the output of which a signal (M) identifying at least one locating direction (.phi.1) of the source is generated.

7. The arrangement as claimed in claim 6, characterized in that the sensor arrangement (1) has at least three of the outputs (A xy) and in that these outputs are operatively connected in pairs to at least two, preferably to three, quotient-forming units (Q I- Q III).

8. The arrangement as claimed in either of claims 6 and 7, characterized in that a time/frequency-domain converter unit (3) is interposed between the outputs (A xy) of the sensor arrangement (1) and the inputs of the quotient-forming unit (Q).

9. The use of the method as claimed in one of claims 1 to 5 or the arrangement as claimed in one of claims 6 to 8 for the locating of acoustic sources.

10. The use as claimed in claim 9 on hearing devices.