1 Method and wideband antenna system to minimise the influence of interference sources TECHNICAL FIELD The invention relates to the field of interference on electronic systems such as jammer interference on radar systems. BACKGROUND ART It is often desirable to minimize the influence of interference sources and also to estimate characteristic parameters of interference sources disturbing an electronic system, such as jammers or unintentional Radio Frequency Interference (RFI) disturbing a radar or a communications system. Today a separate Side Lobe Cancelling system (SLC) is used to minimize the interference from interference sources and a separate ESM (Electronic Support Measurement) receiver is today normally used to estimate interference parameters from the interference sources. The ESM system is also used for other purposes. An alternative is that this function of estimating interference parameters is performed by the electronic system. Both alternatives limit the time available for the actual function of the electronic system as both solutions will occupy the antenna aperture of the electronic system during operation. Antenna availability is a critical factor in Multifunctional systems where an antenna aperture can be used by several systems as e.g. a radar system, ESM system and a communication system. SLC systems are used to cancel e.g. jammer signals picked up in side lobes of a radar stystem. Existing solutions allow jammer signals from several jammer sources to be cancelled. One solution is described in US 4044359 "Multiple Intermediate frequency side-lobe canceller". Side lobes are difficult to avoid when designing antennas and jammer signals can be picked up by these side lobes. As the jammer signals are often powerful they will cause interference with the signal from a target picked up in the main lobe even if the. reception sensitivity of the side lobe is much below the reception sensitivity of the main lobe. The drawback with the existing SLC solutions of 2 today is that only narrow band cancellation of the side lobe is possible. This is a serious problem as radar antennas are often operating over a very wide bandwidth while side lobe cancellation is only effective in a part of the operating bandwidth of the radar antenna. SLC systems can also be used in other applications as e.g. to minimise RFI interference on communication systems. There is thus a need to accomplish an improved method and antenna system for minimizing the influence of interference sources over a wide bandwidth and optionally for estimating interference source parameters from e.g. jammers without the estimation causing interruption of neither the normal function of the electronic system nor the normal ESM function. SUMMARY The object of the invention is to reduce at least some of the mentioned deficiencies with the prior art solutions and to provide: • a method and • a wideband antenna system to solve the problem to achieve an improved method and a wideband antenna system for minimizing the influence of interference sources over a wide bandwidth and optionally for estimating interference source parameters from e.g. jammers without the estimation causing interruption of neither the normal function of the electronic system nor the normal ESM function. Minimisation of the influence of interference sources is achieved by providing a method comprising control of the Signal to Noise/interference Ratio, SNR, of a wideband antenna system connected to an electronic system. The wideband antenna system comprises at least one array of at least two antenna elements/sub arrays. The SNR control comprises establishing of 3 cancellation directions for interfering frequencies in the antenna pattern in the direction of interference sources. The SNR control is achieved by affecting waveforms between the antenna elements and the electronic system with phase shifts or time delays obtained from an optimisation process for maximising the array processing gain of said array wherein the wideband antenna System being operational over a system bandwidth and operating with an instantaneous bandwidth B and wherein the cancellation directions in the direction of the interference sources over the instantaneous bandwidth B, are accomplished by: • transforming means being inserted between at least all but one of the antenna elements and the sub arrays in the wideband antenna system and the electronic system, a sub array comprising at least two sub elements, or the transforming means being integrated in the antenna element/sub array or the electronic system, • parameters, being optimised by using the optimisation process over the instantaneous bandwidth B for maximizing the array processing gain of said array, and • the transforming means affecting the waveforms between at least all but one of the antenna elements and the sub arrays and the electronic system by use of the parameters obtained from the optimisation process over the instantaneous bandwidth B. Estimation of interference source parameters may be achieved by a method comprising estimation of interference source parameters in an evaluation process by: • estimation of Antenna Patterns, AP:s, for at least the frequencies corresponding to the A/spectral components, • locating frequency stable minima in the Antenna Patterns, AP:s, giving the number of interference sources and the direction to these sources and 4 • evaluating attenuation of the Antenna Patterns, AP;s, as a function of frequency in the frequency stable minima directions, giving the bandwidth of the interference sources. Minimisation of the influence of interference sources is further arranged to be achieved by a wideband antenna system through an arrangement to control the. Signal to Noise/interference Ratio, SNR, of the wideband antenna system. The wideband antenna system is connected to an electronic system and comprises at least one array of at least two antenna elements/sub arrays. The SNR control comprises means for establishing of cancellation directions for interfering frequencies in the antenna pattern in the direction of interference sources. The SNR control is arranged to be achieved by affecting waveforms between the antenna elements and the electronic system with phase shifts or time delays obtained from an optimisation process for maximising the array processing gain of said array wherein the wideband antenna system is arranged to be operational over a system bandwidth and arranged to operate with an instantaneous bandwidth B and wherein the cancellation directions in the direction of the interference sources a^er the instantaneous bandwidth B, are arranged to be accomplished by: • transforming means being arranged to be inserted between at least all but one of the antenna elements and the sub arrays in the wideband antenna system and the electronic system, a sub array comprising at least two sub elements, or the transforming means being integrated in the antenna element/sub array or the electronic system, • parameters, being arranged to be optimised by using the optimisation process over the instantaneous bandwidth B for maximizing the array processing gain of said array, and • the transforming means being arranged to affect the waveforms between at least all but one of the antenna elements and the sub arrays and the electronic system by use of the parameters obtained from the optimisation process over the instantaneous bandwidth B. 5 Estimation of interference source parameters may be further achieved by an arrangement for estimation of interference source parameters comprising means for performing an evaluation process to: • estimate Antenna Patterns, AP:s, for at least the frequencies corresponding to the M spectral components, • locate frequency stable minima in the Antenna Patterns, AP:s, giving the number of interference sources and the direction to these sources and • evaluate attenuation of the Antenna Patterns, AP:s, as a function of frequency in the AP frequency stable minima directions, giving the bandwidth of the interference sources. A further advantage is that the invention also provides a JRC module arranged to receive an input comprising the parameters affecting the waveforms via an input connection from the electronic system or via a separate connection to the transforming means. The JRC module comprises means for performing the evaluation process for estimating the interference parameters. The JRC module is arranged to output the result of the estimation via an output connection to the electronic system. Additional advantages are achieved by implementing one or several of the features of the dependent claims which will be explained in the detailed description. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1a schematically shows a digital solution of a realization of the transforming means in the frequency domain. Figure 1b schematically shows an analogue solution of a realization of the transforming means in the frequency domain. 6 Figure 2a schematically shows a realization of the transforming means in the time domain. Figure 2b schematically shows a realization in the time domain for an example of the transforming means including also a dominating non frequency dependent "true time delay". Figure 2c shows a diagram of attenuation/amplification and time delays as a function of angular frequency co (2KJ). Figure 3 schematically shows a block diagram of one example of how control of a wideband array antenna can be implemented. Figure 4 shows the definition of angles cp and d and u- and v-coordinates. Figure 5 shows a flow chart of one iterative optimisation process over the instantaneous bandwidth B to obtain an estimate of the optimum iv-matrix. Figure 6 schematically shows one antenna element composed of several sub elements, compare with £2 in figure 3 . Figure 7 schematically shows an example of a planar array composed of seven hexagonal antenna elements composed of nineteen sub elements each. Figure 8 shows a graph of the convergence of the Normalised Array Processing Gain (NAPG) in the main beam direction as a function of iteration steps. Figure 9 shows the resulting Normalised Array Processing Gain (NAPG), after convergence, as a function of t/v-coordinates. Figure 10 shows the Antenna Pattern (AP) as a function of frequency for five different directions. 7 Figure 11 schematically shows the Antenna Pattern (AP) for each DFT-frequency for the three largest threshold crossings. Figure 12 schematically shows a block diagram of one example of how the invention can be implemented including the estimation of jammer parameters. DETAILED DESCRIPTION The invention will now be described in detail with reference to the enclosed drawings. Henceforth in the description the invention will be exemplified with a radar system as the electronic system which is subject to interference from a jammer, characterized as an intentional interference. The interference can also be caused by an unintentional Radio Frequency Interference (RFI) or clutter picked up in side lobes to the radar antenna and comprising signals reflected from objects within the radar antenna coverage. Henceforth in the description the interference will be exemplified by a jammer unless otherwise stated. The information needed for estimation of the interference parameters are obtained from transforming means or from the electronic system as will be explained. An antenna pattern is defined as radiated power as a function of direction when the antenna is operated in transmit mode and as sensitivity as a function of directions when the antenna is operated in receive mode. A wideband cancellation direction is henceforth in the description used as a direction in the antenna pattern where the radiated power/sensitivity has a 8 minimum being substantially below the radiated power/sensitivity in the direction having the maximum radiation/sensitivity. Figure 1a schematically shows an example of a practical realization of a frequency dependent "true time delay" solution for a wideband array antenna. A wideband array antenna is defined as an array antenna having a bandwidth greater than or equal to an instantaneous operating bandwidth B. The instantaneous bandwidth B is the instantaneous operating bandwidth which will be described further in association with figure 3. In this example a time delay is used as a parameter being frequency dependent. The wideband array antenna comprises at least two antenna elements. The realization also includes an optional frequency dependent attenuation/amplification, i.e. the amplitudes of the waveforms are attenuated or amplified. In this optional embodiment two frequency dependent parameters are used; time delay and attenuation/amplification. Due to the reciprocity principle of antennas the inventive solution is applicable both for transmission and reception. An input waveform suit), 101, from an antenna element n in the wideband array antenna is fed to a Fourier Transformation (FT) unit 102 using for example a Fast Fourier Transformation (FFT), but other methods for calculation of the spectrum could be used. The FT unit transforms the instantaneous bandwidth B of the input waveform Si„{t), 101, into M spectral components 0 to M-\, in this example into 8 spectral components 110-117, each spectral component having a centre frequency/,,. However the transformation can be made into more or less spectral components. The time delay r„, (120-127) and the optional frequency dependent attenuation/amplification a,„ (130-137) are affecting each spectral component m through any suitable time delay and/or attenuation/amplification means well known to the skilled person. The spectral component 110 thus has a time delay to, 120, and an attenuation/amplification OQ, 130, the spectral component 111a time delay TI, 121, and an attenuation/amplification a\, 131, and so on until the spectral component 117 having a time delay T?, 127, and an attenuation/amplification an, 137. All spectral components are fed to an Inverse Fourier Transformation 9 (IFT) unit, 103, using Inverse Fast Fourier Transformation (IFFT) or any other method, as for example IDFT (Inverse Discrete Fourier Transformation), transforming from the frequency domain to the time domain thus transforming all the spectral components back into the time domain and producing an output waveform Sou/(t), 104. The time delay T„, and the attenuation/amplification a,„ are examples of parameters for antenna element n affecting each spectral component m where the parameters are frequency dependent. The general designation for these element number and frequency dependent parameters are r„„, and a„„, where n ranges from Oto N-\ and m from 0 to A/-1. The FT unit, the time delay and attenuation/amplification means and the IFT unit are parts of a first control element 100. The invention can be implemented using only the frequency depending time delay r( 104- A frequencyy^ of each spectral component can be calculated according to: /„ = /, + m — Jm Jc 2 A/ 12 for a case with equividistant spectral component division .where fc is the centre frequency in the frequency band with an instantaneous bandwidth B. The instantaneous bandwidth B is the instantaneous operating bandwidth. The third control element 150 comprises M band pass filters F„, means for time delay and amplification/attenuation as well as the summation network 151. A further digital realization will now be described with reference to figures 2a and 2b. In many situations a time discrete realization, with discrete steps T in time, might be preferable. An output waveform SouimT) emitted from a second control element (200) can then be calculated with the aid of equation (2) as a function of an input waveform Si„{m-T) entering the second control element. The index m is an integer value increasing linearly as a function of time. W{(o^ represents the time delay and attenuation/amplification of spectral component m, see figure 1. The FFT and the IFFT described in association with figure la, both requiring Mlog2(A/) operations, are computational efficient methods for calculation of DFT (Discrete Fourier Transform) and IDFT (Inverse Discrete Fourier Transform), both requiring A^ operations. A/is as mentioned above the total number of spectral components. The output waveform is calculated as: -/W m=o /=o V ^ ' DFT of the input signal i,„(i(:T) > ^ ' IDFT back to the time domain M-\ 1 M-\ /7^„*-' V ^ ' (2) IDFT{»'(^„)}=v.^(,.,^(^.„j M-S 'in Q-T)' ^.od[(*-/).(A/-l)] = 'in (k-T)® W^,,f,.(;^_,)3 mod[x,>'] = remainder after division of ;f by>' 13 (Om = 2•^:;^=discrete angular frequency M= Number of spectral components / = integer raising variable used in the DFT and the IDFT k = integer raising variable for discrete time steps /M = integer raising variable for spectral components and integer raising variable used in the DFT. As can be seen in equation (2) the desired functionality in a time discrete realization can be achieved with Af operations. FFT and DFT are different methods for Fourier Transformation (FT). IFFT and IDFT are corresponding methods for Inverse Fourier Transformation (IFT). As described above these methods have different advantages and the method most suitable for the application is selected. However any of the methods can be used when FT and/or IFT are/is required in the different embodiments of the invention. Figure 2a shows the input waveform Si„{mT) 201, coming from an antenna element in the wideband array antenna. The input waveform 201 is successively time delayed in MA time steps T, 203, numbered from 1 to M-1 and being time delayed copies of the input waveform SiJjnT). The input waveform is thus successively time delayed with time steps T as illustrated in the upper part, 204, of Figure 2a. M parameters comprising weighting coefficients w„^o to W„_M.\, for antenna element n is identified with two indexes, the first representing antenna element number and the second a consecutive number m representing a spectral component and ranging from 0 to A/-1. The weighting coefficients w„fi to W„,M.\ thus is the weighting coefficient for antenna element n. The arrows 211 illustrate that the input wavefonn Si„{mT) is multiplied with the first weighting coefficient w„,o and each time delayed copy of the input waveform is successively multiplied with the weighting coefficient having the same second index as the number of time step delays T included in the time delayed copy of the input wavefonn as illustrated in the 14 middle part, 205, of Figure 2a. The result of each multiplication is schematically Illustrated to be moved, indicated with arrows 212, to the bottom part, 206, of Figure 2a, where each multiplication result is summarized to the output wavefonm 207, SouimT). The dominating part of the time delay is not frequency dependent in a large antenna array (antenna array size considerably greater than the wavelength), resulting in many very small consecutive weighting coefficients, approximately equal to zero, at the beginning and end of the series of weighting coefficient w„fi to W„,M.X for each antenna element. Assume that the first X weighting coefficients and the last y weighting coefficients in the series of weighting coefficients w„fi to W„,M.\ are approximately equal to zero. It could then be suitable in a hardware realization, to set the first x weighting coefficients and the last y weighting coefficients to zero and to integrate the first X time delays T into a time delay D, 202, equal to xT as illustrated in figure 2b, and to exclude the last y multiplications to reduce the number of required operations to less than M operations. Figure 2b otherwise corresponds to figure 2a. The time delay D, 202, corresponds to the non frequency dependent time delay, for each antenna element. The remaining frequency dependent time delay is called "delta time delay". Figure 2b is an example of a computational efficient convolution, for calculation of the "delta time delay", preceded of the frequency independent time delay D, 202, used mainly for control of the main lobe direction for large antenna arrays. The means for realizing the frequency independent time delay D and the means for frequency dependent time delays and attenuations/amplifications for each time delay T, are parts of the second control element 200. Figure 2c shows an example of the frequency dependency of the time delay r and attenuation Aid) on the vertical axis 215 as a function of co {i.e. l-nj) on the horizontal axis 216. The time delay as a function of co then forms a curve 217 and the attenuation/amplification a curve 218. 15 Figure 2a and 2b thus shows a realization of a frequency dependent time delay and attenuation/amplification in the time domain and figure 1a and 1b shows a corresponding realization in the frequency domain. An advantage with the realization in the time domain is that only M operations are required while the realization in the frequency domain requires M\og2{M) operations as described above. All three control elements could as mentioned earlier be inserted either at video, intermediate frequency (IF) or directly on radio frequency (RF) level. It is easier to realize the control element at lower frequency but all hardware needed between the control element and the antenna element/sub array need to be multiplied with the number of control elements. In the description the invention is henceforth described as being realized at the RF level. The three control elements are examples of transforming means, transforming an input waveform to an output waveform. The transforming means all have two ends, an input end receiving the input wavefomi and an output end producing the output waveform. Figure 3 schematically shows a block diagram of one example of how the control of a wideband array antenna can be implemented. Figure 3 shows the situation when the wideband array antenna 301 is working in receive mode. A wideband array antenna is defined as an array antenna having a bandwidth greater than or equal to the instantaneous operating bandwidth B. This bandwidth of the wideband array antenna is called the system bandwidth of an electronic system ES, 303 using the wideband array antenna. The electronic system may comprise receiver/s or parts of receiver/s and nomially also transmitter/s or parts of transmitter/s. The instantaneous bandwidth B is the instantaneous operating bandwidth of the electronic system. The system bandwidth is the difference between the highest frequency and the lowest frequency over which the system can 16 operate. In all practical usable systems is the instantaneous bandwidth B smaller than or equal to the system bandwidth. The wideband array antenna can optionally comprise one or several sub-arrays, each sub-array comprising two or more sub elements, e, preferably internally controlled by phase shifters and/or time delays. There are a total of N antenna elements, E\ to EN, and in this example a corresponding number of transforming means Tr\ to Trfj, An antenna element can also be a sub array. One transfomiing means is, in this example, inserted between each antenna element or sub arrays and the electronic system ES, 303, which e.g. can be a radar system, an ESM system or a communication system. Tri is inserted between £i and the electronic system, 7>2 between £2 and the electronic system and so on until TKN being inserted between EN and the electronic system ES, i.e. 7>„ is inserted between corresponding antenna element or sub array E„ and the electronic system ES. A wideband array antenna unit is defined as the wideband array antenna and the transforming means. In figure 3, £2 is a sub array comprising three sub elements e. The input waveform in figure 3, SmiO or Si„{mT), 306, is emitted from each antenna element or sub array and fed to the corresponding transforming means. The output waveform Souit) or SouimT), 307, is fed to the electronic system 303. The waveforms 306 and 307 are individual for each antenna element or sub array. The parameters affecting the waveforms can be generated in the ES and then fed to the transforming means or the generation of the parameters can be performed in the transforming means. Angles d and ^ are used to define a direction in space and are defined as illustrated in figure 4. In a Cartesian coordinate system with X-axis 401, Yaxis 402 and Z-axis 403 the direction to a point 404 in space is defined by an angle 6, 405, and an angle (p, 406. The angle ^ is the angle between a first line 407 from the origin 408 to the point 404 and the Z-axis. The angle 6 is the angle between a second line 409 being the orthogonal projection of the line 407 on the X-Y plane and the X-axis. In an wv-coordinate system the first 17 line 407 represents a unit vector r being the unit vector in the observation direction. The projection of the second line 409 on the X-axis represents an w-coordinate, u, and the projection on the Y-axis represents a v-coordinate, v. As mentioned above the transforming means are normally inserted between each antenna element or sub array and an electronic system ES. The transforming means are connected either directly or indirectly to an antenna element or sub array at one end and either directly or indirectly to the electronic system at the other end. In one embodiment when the transforming means are inserted at video level, one end of the transforming means can be directly connected to the electronic system and the other end indirectly connected to an antenna element or sub array via electronic hardware such as mixers. In another embodiment when the transforming means are inserted at RF-level, one end of the transforming means can be directly connected to an antenna element or sub array and the other end directly to the electronic system. The required mixer hardware in this embodiment is included in the electronic system. In yet another embodiment when the transforming means are inserted at IF-level one end of the transforming means can be indirectly connected to an antenna element or sub array via electronic hardware such as mixers and the other end indirectly connected via electronic hardware such as mixers to the electronic system. The transforming means can be separate units or integrated in the antenna elements or sub arrays or in the electronic system. The wideband antenna system and conresponding method can comprise an array antenna with at least two antenna elements/sub arrays, i.e. the wideband array antenna, or a main antenna and a wideband auxiliary antenna, each comprising at least one antenna element. If the wideband antenna system comprises a main antenna and a wideband auxiliary antenna the main antenna can be any type of antenna comprising one or several antenna elements, e.g. a radar antenna, and the wideband auxiliary antenna 18 can be a single antenna element or an array of antenna elements/sub arrays. An antenna element can also be a sub array comprising at least two sub elements, as illustrated with sub array E2 in figure 3. A wideband control of the Signal to Noise/interference Ratio, henceforth called the SNR, over the instantaneous bandwidth B is accomplished by the transforming means 100, 200, 150, Trx-Trn being inserted, or arranged to be inserted, between at least all but one of the antenna elements or sub arrays {E\-EN) in the wideband array antenna and the electronic system 303 and between at least all but one of the antenna elements or sub arrays in the combined main antenna and wideband auxiliary antenna and the electronic system 303. The transforming means can also be integrated, or arranged to be integrated, in the antenna element/sub array or the electronic system. This means that at least all but one of the waveforms from the antenna elements or the sub arrays in the wideband array antenna or at least all but one of the waveforms from the combined main antenna and wideband auxiliary antenna have to pass through transforming means. A common solution is that the transforming means 100, 200, 150, Tr\-Trs are inserted, or arranged to be inserted, between ail of the antenna elements or sub arrays {E\-EN) in the wideband array antenna and the electronic system (303) and between all of the antenna elements or sub arrays in the wideband auxiliary antenna and the electronic system 303. In the situation where the wideband antenna system comprises a main antenna with one antenna element, or sub array, and a wideband auxiliary antenna with at least one antenna element it is sufficient that a transforming means is connected only to the antenna elements of the wideband auxiliary antenna and that the output wavefomis from the transforming means is added to the waveform of the main antenna. The main antenna does not necessarily have to be connected to the transforming means. The important aspect is that at least two waveforms are interacting, where all waveforms, or all waveforms but one, have been transmitted through a transforming means. 19 In the case where one waveform is not affected by a transforming means this wavefomi serves as a reference and the parameters for the transforming means affecting the other waveforms are adapted to this reference. This principle is, as mentioned above, also true for the wideband array antenna where one of the antenna elements or sub arrays can be without a transforming means. When the wideband antenna system is realized with a main antenna and a wideband auxiliary antenna, the main beam is defined as the main beam of the main antenna. An instantaneous wideband waveform has at every moment a wide bandwidth. This is in contrast to e.g. a stepped frequency waveform that can be made to cover a wide bandwidth by switching to different narrow frequency bands. A wavefomi with the instantaneous bandwidth B is defined as narrow band if BL 28 The remaining problem is to find the weighting coefficients w„_m that maximize tiAPG{w,6MB, (PMB)- This is done, in this example, by iteration of w„,m in the direction with "steepest ascent". It should be noted that the numerator of HfKPG{w,6MB, (pm) could be calculated and that the denominator could be measured, with the transmitter switched off. for each set of weighting coefficients w„^„. In each iteration all complex partial derivatives of HfKPG{w,em, ,0MB, + A5-c?„,„).^^,.^^,]|-|NAPG[(H;-A5-d>„,),^^,,^^,]| 2-As |NAPG[(H> + y-A5-<^„,,),^^,,-y-A.9-^„,),^^,,ff^,]| •^ 2-Ay (10) In equation (10) abovey denotes the imaginary part of a complex expression. A partial derivative of a functiony(xi,...p(:„) in the direction x, at the point {a\,...,a„) is defined to be: df{ao-,a„)^^^^f{au...,a^ + h,...,a„)-f{a„...,a„) dx, A-o h The scalar "step length" As is a small adjustable value. 29 A new updated matrix of weighting coefficients, w^^, is calculated by updating a previous matrix of coefficients, w<,w, according to equation (11) below. ^ne. = '^old+^'(^ (11) In equation (11) As is the scalar "step length" and if^M,, Woid, and G all are matrixes with A^ rows and M columns. The scalar "step length" As can be adjustable, e.g. in 3 dB steps, to maximise the ratio, ANAPGMBI of the "new" and "old" in the main beam direction: ANAPGMB= |NAPGKe».,^A/5,^Wl / \^fi^PG(WM,OMB,.) I / I NAPGMB(H'.W) I has converged towards unity where the scalar "step length" Ay is a small adjustable value, and where the ^-matrix includes all partial derivatives of NAPGMB with respect to the continuously updated w„ew matrix. The flow chart of figure 5 shows the iteration steps from Wstan to Wnew in the optimisation process over the instantaneous bandwidth B, 500. The H'-matrix is assigned a start value Wstan in starting step 501. In initiating step 502 a wmatrix Wou and w„e»^ both are assigned the value of Ws,ar,. An outer first "ifloop" 503 continues until the ANAPGMB only exceeds 1 by less than S, as will be decided in a second if-step 514. After the initiating step 502 has been performed the first "for-loop" « = 0....(A^-1) is started in a first "for start" step 506 after which the second "for-loop" m = 0....(A/-1) is started in a second "for start" step 507. After the two "for-loops" have been started the estimate of all 30 partial derivatives, g„,m are performed In the derivatives step 508. g„,„ is calculated as ANAPGMB divided with ^w„_„ as described above. When both "for-loops" have been run through, the complete complex matrix G{W,0MB,,0MB,--H'„,«-%[K-'")-7'+'-.(^.^)-^(^.«')] ''Tol "=0 "'=0"=0"'=0 ii.0i.'=0in=0 and M''"*^"^ is equal to the IDFT of fV°''^"\ see equation (14) and equation (15) below. The superscript row(«) stands for row number « of a weighting matrix comprising the weighting coefficients for all antenna elements. Each row in the weighting matrix thus comprises the M weighting coefficients for antenna element n. Consider an example with M time domain weighting coefficients in each transforming means. Use the time domain weighting coefficients obtained after convergence in the iterative process described in association with figure 5. These time domain weighting coefficients can now be transformed to M frequency domain weighting coefficients one for each transforming means according to equation (14). The first frequency domain coefficient {m = 0) for each transforming means can now be used to calculate the narrowband array factor for the first spectral component. The calculation for the first spectral component is made according to equation (16) with/equal to the frequency of the first spectral component. The second frequency domain coefficient for each transforming means can in a similar way be used to calculate the narrowband Antenna Pattern, AP, for the second spectral component, and so on. A/Antenna Patterns, F{f,0,- matrix is equal to the IDFT of row n of the >f-matrix. The transforming means coefTicients, w„,m, obtained after 200 iterations can now be used to calculate the frequency domain weighting coefficients, W„,„, by usage of a DFT for each sub array. When the >f-matrix is known the Antenna Pattern (AP) can be estimated for any frequency with the aid of equation (16) below. < = j= =j > ^ - I /^.(«)-l S fvAf.")- Z "•..-. (16) • r„ Is the vector from the antenna system phase centre (origo) to the phase centre of element n. • r„ „e Is the vector from the phase centre of element n to the phase centre of sub element tie. • On.ne Is a complex weighting coefficient within antenna element n for sub element««. Weighting between antenna elements are done by the coefficients, w. • n e (0, l...(AM)] Integer raising variable for antenna elements. A^ is equal to the number of antenna elements 42 • «« e [0, l...(A^,-l)] Integer raising variable for sub elements. Ne is equal to the number of sub elements in each antenna element Where the frequency continuous sub array weights, Wc{f,ri), see equation (17) are interpolated from the W'-matrix according to the pages 31-35 in P.M. Woodward, Probability and Information Theory, with applications to Radar, Pergamon Press Ltd., London, England, 1953. The result can be expressed as indicated in equation (17) below. »;(/.«)= S"V^|,.„,„.sinc(;r.{M.[r.(/-/„)+l]-m))(,7, m=0 With the aid of equations (16) and (17) it is possible to calculate the single frequency AP for arbitrarily frequencies, within the instantaneous bandwidth 5, in arbitrarily directions. In figure 10 the Antenna Pattern, AP, according to equation (16) expressed in dB, is plotted on an Y-axis 1001 as a function of frequency on an X-axis 1002 for four different directions: • The main beam direction, 1003 • The direction of jammer number 1,1004 • The direction of jammer number 2,1005 • The direction of jammer number 3,1006 • An arbitrarily chosen direction, 1007, with the unit vector equal to: [ -0,200 -0,200 0,959 ] All "DFT-frequencies" /„ within the instantaneous bandwidth B of the waveform. 43 . . B B Jn, Jc ^ A/ are marked by filled triangles, 1008, in figure 10. It is noticed that minima's within the instantaneous wavefomi bandwidth coincide with the "DFTfrequencies" in the Jammer directions. Figure 10 reveals that deep, frequency stable, local minima for each DFT-frequency combined with low average level results after the iteration process in the jammers directions. This is in contrast to the arbitrarily chosen direction. 1007, with the unit vector equal to: [-0,200 -0.200 0,959]. This observation is used for an automated evaluation process of the invention which will now be described and is used to estimate the number of jammers and the direction to each of them. A frequency stable minima is a minima that remains in the same direction over at least a part of the instantaneous bandwidth B, such as at least 1%, preferably at least 5%, more preferably at least 25% and most preferably 50% of the instantaneous bandwidth B, but preferably not over the complete instantaneous bandwidth B such that the minima remains stable over not more than 90% of the instantaneous bandwidth B and preferably over not more than 80% of the instantaneous bandwidth B, and more preferably over not more than 70 % of the instantaneous bandwidth B. The location of these minima can be made by manual means by comparing Antenna Patterns for at least each DFT frequency. It can also be made in an automated process included in an example which now will be described. In the example below it is assumed that each jammer occupies at least 50% of the instantaneous bandwidth B, which means that the minima shall remain stable over a portion of at least 50% of the instantaneous bandwidth B. However, depending on the application, the jammed portion of the instantaneous bandwidth B needed for defining the minima as frequency stable can be both above and below 50% of the instantaneous bandwidth B. The portion chosen depends on the desired accuracy accepted in the estimation of the number of jammers. A small portion increases the risk of over estimating the number of jammers 44 and a big portion increases the risk of under estimating the number of jammers. The following procedure is used to estimate the number of jammers and the direction to each of them: • The Antenna Pattern, AP, is calculated for each DFT-frequency and for each frequency right lietween each pair of consecutive DFT-frequencies for all m'-coordinates in a quadratic grid with 401 points in the range from -1 to +1 along the u and v-axis respectively inside the unit circle where u = sin(^)cos(^ and v = s\n{(p)s\n{0). 0, q),u and v are defined in figure 4. The result from each grid point, ((/, V) Ued.AQO, Fe0..400, is stored in a vector .4/*{/.j'containing 2A/+1 values. Each value in the veciox APu.v corresponds to one of the above mentioned frequencies, numbered consecutively from 0 to 2M • In each of the above mentioned grid points the ratio in equation (18) is calculated for all combinations of F ^ and Fhigh, where Fio„ 8,5000-8.5625 9,3125-9.3750 -8,94 -812 0.870-0.035 60.5° -2.0° 2.. 8.5000 - 8.5625 9.4375 - 9.5000 -9.00 -937 0.005 0.170 0.3° 9.8° 3 [8.6875-8.750019,4375-9,5000 I -9.09 | -750 |-0,500 10,000 [-30.0° | 0,0° Table 3 Estimated parameters for each threshold crossing. • Az is the Azimuth angle and El is the elevation angle. • fmax is the frequency span between the highest DFT-frequency with an . attenuation higher than 50 dB and the following DFT-frequency 48 • fmin is the frequency span between the lowest DFT-frequency with an attenuation higher than 50 dB and the previous DFT-frequency The example of an evaluation process for estimating the interference source parameters described above Is one example of how the evaluation process can be achieved in an example well suited for automation. The evaluation process can however be made in different ways Including other automated evaluation processes than the one described above, or other more or less ' automated evaluation processes, including also a completely manual evaluation, as long as following general steps, for the evaluation process of the invention are included for achieving estimation of interference source parameters: • estimation of Antenna Patterns, AP:s, for at least the frequencies corresponding to the A/ spectral components, • locating frequency stable minima in the Antenna Patterns, AP:s, giving the number of interference sources and the direction to these sources and • evaluating attenuation of the Antenna Patterns, AP.s, as a function of frequency in the frequency stable minima directions, giving the bandwidth of the interference sources. The invention also includes an arrangement for the three general steps mentioned above, for achieving estimation of interference source parameters comprising means for performing an evaluation process to: • estimate an Antenna Patterns, AP:s, for at least the frequencies corresponding to the M spectral components, • locate frequency stable minima in the Antenna Patterns, AP:s, giving the number of interference sources and the direction to these sources and 49 • evaluate attenuation of the Antenna Patterns, AP:s, as a function of frequency in the frequency stable minima directions, giving the bandwidth of the interference sources. In the evaluation process above the estimation of interference parameters has been illustrated in the time domain using the »v-matrix and v/ith the Mv-coordinate system. The invention can however also be realized in the frequency domain using the W-maU\x and with any suitable coordinate system. In the general case using an arbitrary coordinate system and when vyorking in the time- or frequency domain the evaluation process of the invention can be described in more detail as follows: • the Antenna Pattern, AP^ is estimated, or arranged to be estimated, for each of the frequencies corresponding to the M spectral components and for each frequency right between each pair of consecutive such frequencies for all directions of interest, • for each direction of interest a ratio R is calculated, or arranged to be calculated, having a high value for interference directions and considerably lower values in non-interference directions, • the ratio R is compared, or arranged to be compared, with a threshold, chosen to a suitable level related to the maximum value of the ratio R • the number of crossings of the ratio R defines the number of interference sources, • the direction to the interference source/s is defined by the direction/s corresponding to the crossing/s, • the Antenna Pattern, AP, is calculated, or arranged to be calculated, for each of the frequencies corresponding to the M spectral components in the directions of the crossings and • the bandwidth of the interference source is given by evaluating, or by means for evaluating, the Antenna pattern, AP, in the direction of the crossings as a function of frequency. 50 In this general case the ratio Ru.y is exchanged to the ratio R being independent of the selected coordinate system. The ratio R is calculated for each direction of interest according to: 2-(F,,,,-l)+l pip p \ _ m=2(F„,-H)-l If the estimates in Table 3 are compared with the assumptions and input values used in our example it is obvious that: • Threshold crossing # 1 corresponds to Jammer number 3 • Threshold crossing # 2 corresponds to Jammer number 2 • Threshold crossing # 3 corresponds to Jammer number 1 51 With this observation it is possible to compare the jammer input values with the estimates. This comparison between jammer assumptions and estimates are summarised in Table 4 below. Parartveterifi ^?v ilammei^number-l Jammer hunriber|2 Jammer,number3 , I Input value' 9,10 GHz 9,00 GHz 8,90 GHz Centre Estimation 9,09 GHz 9,00 GHz 8,94 GHz frequency "^ Error 10 MHz OMHz 40 MHz ~' Input value"" 800 MHz 1000 MHz 800 MHz Bandwidth Estimation 750 MHz 937 MHz 812 MHz Error 50 MHz 63 MHz 12 MHz Input value -30,0° OjO° 60^0° Azimuth , Estimation -30.0° 0,3° 60,5° angle Error 0,0° 03° 0,5° ^^ Input value 0^0° 10^0° 0^0° Elevation '' Estimation 0,0° 9,8° -2,0° angle ^^ Error 0,0° 0,2° 2,0° Table 4 Comparison between jammer assumptions and estimates ^ Jammer spectrum centre frequency within the receiver bandwidth, equal to the centre frequency of: ({[/"c«-5«/2 .../CR+BR/I] n [fcrBjfl ...fcj^BA]}) where 0 represents intersection. ^ Jammer spectrum bandwidth within the receiver bandwidth, equal to the bandwidth of: ({[/c«-B/?/2 .../CR+BRII] n \fcj-Bjll ...fcf^Bj/2]}) where n represents intersection. Based only on the weighting coefficients obtained after convergence we have drawn the following conclusions: • There are three jammers i • The azimuth directions to the jammers are approximately -30°, 0°, and ] 60° respectively 52 • The bandwidth of the jammers are estimated to: o Approximately 8,6 GHz to at least 9,5 GHz for the jammer In the direction close to -30° o At least from 8,5 GHz to at least 9,5 GHz for the jammer in the direction close to 0° o At least 8,5 GHz to approximately 9,4 GHz for the jammer in the direction close to 60°, An advantage with the evaluation process of the invention is that the time available for the actual function of the electronic system is not limited as the evaluation process for estimating the interference parameters will not occupy the antenna aperture of the electronic system during operation. The estimation of interference parameters is accomplished by just using the same parameters affecting the waveforms as used for minimising the interference. The estimation of interference parameters does thus not cause interruption of neither the normal function of the electronic system nor the normal ESM function. This is advantageous as antenna availability is a critical factor in fy/lultifunctional systems where an antenna aperture can be used by several systems as e.g. a radar system, ESM system and a communication system. Figure 12 schematically shows a block diagram of one example of how the invention can be implemented including also the estimation of the jammer parameters. Figure 12 shows the situation when the wideband array antenna 1201 is working in receive mode. The wideband array antenna can optionally comprise one or several sub-arrays, each sub-array comprising at least two sub elements, e. There are a total of N antenna elements, E\ to EN, and in this example a corresponding number of transforming means Tr\ to Tr^. An antenna element can also be a sub array. One transforming means is, in this example, inserted between each antenna element or sub array and the electronic system ES, 1203, which e.g. can be a radar system, an ESM system or a communication system. Tr\ is inserted between E\ and the electronic system, 7>2 between Ei and the electronic system and so on until 53 TrN being inserted between EN and the electronic system ES, i.e. Tr„ is inserted between corresponding antenna element or sub array E„ and the electronic system ES. A wideband array antenna unit is defined as the wideband array antenna and the transforming means. In figure 12, £2 is a sub array comprising three sub elements e. The input waveform in figure 12, sjj) or Si„(mT), 1206, is emitted from each antenna element or sub array and fed to the corresponding transforming means. The output waveform SoulO or SouimT), 1207, is fed to the electronic system 1203. The waveforms 1206 and 1207 are individual for each antenna element or sub array. The parameters affecting the wavefonns can be generated in the ES and then fed to the transforming means or the generation of the parameters can be performed in the transforming means. In this example the generation of the parameters is performed in the ES and fed via an input connection 1208 to the transforming means and a separate Jammer, RFI, Clutter module, JRC, 1210. In this example the JRC module is thus arranged to receive an input, via the input connection 1208, comprising the parameters affecting the waveforms from the electronic system ES, 1203. In other realization this input information to the JRC module can be arranged to be received from the transforming means via a separate connection to the transforming means in case the generation of the parameters is performed in the transforming means. The parameters arranged to affect the waveforms can comprise the weighting coefficients in the H'-matrix or the W'-matrix. The JRC-module comprises means for performing the evaluation process for estimating the interference parameters and the JRC module is arranged to output the result of the estimation via an output connection 1209 to the electronic system, ES. In this example the complete H'-matrix or the complete W-matrix is transferred to all transforming means and the JRC-module. The transforming means are then only using the row of the matrix applicable for the antenna element to which it is connected. In another realization each transforming means only receives the row of the M^-matrix or the W'-matrix from the electronic system ES applicable to the antenna element or sub array to which the transforming means is connected. The JRC-module, however, always receives the 54 complete H'-matrix or the complete ff-matrix, these matrixes being examples of parameters affecting the waveforms. However as mentioned earlier the weighting coefficients can be organized in any suitable way, e.g. as vectors or the transpose of the w- and the ^F-matrix meaning that columns and rows are switched, i.e. a weighting coefficient w„^„ becomes w„,„„ Each transforming means does not either need to use the same number of weighting coefficients, as described. The JRC-module always receives the complete set of parameters affecting the waveforms. The JRC-module can also be incorporated in the electronic system ES or any computer available on a platform supporting the ES or connected to the platform via suitable communication facilities. The parameters affecting the waveforms are thus used for three purposes: • to maintain the main beam in the selected direction as the parameters affecting the waveforms are based on a defined main beam direction • to create wideband cancellation directions in the direction of interference sources by the transforming means affecting the waveforms with the parameters obtained in the optimisation process over the instantaneous bandwidth B • to estimate interference parameters by means of an evaluation process based on the parameters obtained in the optimisation process over the instantaneous bandwidth B. The invention is not limited to the embodiments and examples described above, but may vary freely within the scope of the amended claims. An example of this is a variation of the embodiment described in figure 1a. In the embodiment described in figure 1a the transforming means is inserted between each antenna element and the electronic system. A variation of this solution within the scope of the invention is that a common IFT unit is used 55 for all antenna elements/sub arrays, i.e. the waveform from each antenna element/sub array Is processed In a separate FT unit for each antenna element/sub array but the sum of the spectral component m from each antenna element/sub array after suitable time delay or phase shift and/or attenuation/amplification are processed in a common IFT unit. CLAIMS 1. A method to minimise the influence of interference sources by control of the Signal to Noise/interference Ratio, SNR, of a wideband antenna system connected to an electronic system (303. 1203) and comprising at least one array of at least two antenna elements/sub arrays {E\-EN), the SNR control comprising establishing of cancellation directions for interfering frequencies in the antenna pattem in the direction of interference sources, the SNR control being achieved by affecting waveforms between the antenna elements and the electronic system (303, 1203) with phase shifts or time delays obtained from an optimisation process for maximising the array processing gain of said array, c h a r a c t e r i z e d in that the wideband antenna system being operational over a system bandwidth and operating with an instantaneous bandwidth B and in that the cancellation directions in the direction of the interference sources over the instantaneous bandwidth B, are accomplished by: • transforming means (100, 200, 150, Trx-Tr^) being inserted between at least all but one of the antenna elements and the sub arrays {Ei-Etj) in the wideband antenna system and the electronic system (303, 1203), a sub array comprising at least two sub elements, or the transforming means being integrated in the antenna element/sub array or the electronic system, • parameters, being optimised by using the optimisation process over the instantaneous bandwidth B (500) for maximizing the array processing gain of said array, and • the transforming means (100, 200, 150, Tn-Trs) affecting the waveforms between at least all but one of the antenna elements and the sub arrays {E[-E{i) and the electronic system (303, 1203) by use of the parameters obtained from the optimisation process over the instantaneous bandwidth B. 57 2. A method according to claim 1, c h a r a c t e r i z e d in that the parameters are weighting coefficients being organized in a weighting matrix comprising A^ rows, one row for each transfonming means, each row having M weighting coefficients, and that the weighting matrix is optimised by using the optimisation process over the instantaneous bandwidth B (500) for maximizing the array processing gain of said array, each weighting coefficient in the NxM weighting matrix being defined as a parameter, M being a number corresponding to the number of spectral components. 3 A method according to claim 1 or 2, c h a r a c t e r i z e d in that the wideband antenna system comprises: • a wideband array antenna having an array of at least two antenna elements/sub arrays or • a main antenna and an wideband auxiliary antenna, the auxiliary wideband antenna being a single antenna element or an array of antenna elements/sub arrays. 4. A method according to any one of claims 1-3, c h a r a c t e r i z e d in that the transforming means (100, 200, 150, Tr\-Trs) being inserted between all of the antenna elements or sub arrays {E\-EN) in the wideband array antenna and the electronic system (303, 1203) and between all of the antenna elements or sub arrays in the wideband auxiliary antenna and the electronic system (303, 1203), or the transforming means being integrated in the antenna element/sub arrays or in the electronic system. 5. A method according to any one of claims 1-4, c h a r a c t e r i z e d in that the parameters in the weighting matrix used to affect the waveforms between antenna elements/sub arrays are: • the weighting coefficients of a weighting matrix W'obtained from the optimisation process over the instantaneous bandwidth B for A/ spectral components for each of the transforming means, thus 58 resulting in a >F-matrix having M columns and N rows, N being equal to the number of antenna elements and sub arrays or • the weighting coefficients of a corresponding weighting matrix w obtained from the optimisation process over the instantaneous bandwidth B In the time domain , each row being the Inverse Fourier transformation of the corresponding row in the W'-matrix. 6. A method according to any one of claims 1-5, c h a r a c t e r i z e d in that the optimisation process over the instantaneous bandwidth B is estimating the w-matrix resulting in the maximum Normalized Array Processing Gain, NAPG, for a known Main Beam direction, NARGMB. for the wideband array antenna or the wideband auxiliary antenna combined with a main antenna. 7. A method according to claim 6, c h a r a c t e r i z e d in that the NARGMB, is maximized by calculating a new iv-matrix, w„ew by continuously adding a scalar step As multiplied with a (7-matrix to an old iv-matrix Wou until the ratio: ANARGMB= |NAPGMB(M'„e„)l / I NARGMBC^aw) I has converged towards unity where the scalar "step length" AJ is a small adjustable value, and where the (7-matrix includes all partial derivatives of NARGMB with respect to the continuously updated w„e„ matrix. 8. A method according to any one of claims 1-7, c h a r a c t e r i z e d in that estimation of interference source parameters is achieved in an evaluation process by: • estimation of Antenna Rattems, AR:s, for at least the frequencies corresponding to the M spectral components, • locating frequency stable minima in the Antenna Ratterns, AR:s, giving the number of interference sources and the direction to these sources and 59 • evaluating attenuation of ttie Antenna Patterns, AP:s, as a function of frequency in the frequency stable minima directions, giving the bandwidth of the interference sources. 9. A method according to claim 8, c h a r a c t e r i z e d in that: • the Antenna Pattem, AP, is estimated for each of the frequencies corresponding to the M spectral components and for each frequency right between each pair of consecutive such frequencies for all directions of interest, • for each direction of interest a ratio R is calculated, having a high value for interference directions and considerably lower values in noninterference directions, • the ratio R is compared with a threshold, chosen to a suitable level related to the maximum value of the ratio R • the number of crossings of the ratio R defines the number of interference sources, • the direction to the interference source/s is defined by the direction/s corresponding to the crossing/s, • the Antenna Pattern, AP, is calculated for each of the frequencies corresponding to the M spectral components in the directions of the crossings and • the bandwidth of the interference source is given by evaluating the Antenna pattern, AP, in the direction of the crossings as a function of frequency. 10. A method according to any one of claims 8-9, c h a r a c t e r i z e d in that the Antenna Pattern, AP, is estimated according to: 60 n=0 n,=0 N-\[ K(")-i 1 I n=0 rt,=0 11. A method according to any one of claims 8-9, c h a r a c t e r i z e d in that the ratio R is calculated for each direction of interest, according to: 2.(F„^,-1)+1 12. A wideband antenna system arranged to minimise the influence of interference sources by an arrangement to control the Signal to Noise/interference Ratio, SNR, of the wideband antenna system connected to an electronic system (303,1203) and comprising at least one array of at least two antenna elements/sub arrays {E\-EN), the SNR control comprises means for establishing of cancellation directions for interfering frequencies in the antenna pattern in the direction of interference sources, the SNR control being arranged to be achieved by affecting waveforms between the antenna elements and the electronic system (303, 1203) with phase shifts or time delays obtained from an optimisation process for maximising the array processing gain of said array, c h a r a c t e r i z e d in that the wideband antenna system being arranged to be operational over a system bandwidth 61 and arranged to operate with an instantaneous bandwidth B and in that the cancellation directions in the direction of the interference sources over the instantaneous bandwidth B, are arranged to be accomplished by: • transforming means (100, 200, 150, Tr\-TrN) being arranged to be inserted between at least all but one of the antenna elements and the sub arrays {E\-EN) in the wideband antenna system and the electronic system (303, 1203), a sub array comprising at least two sub elements, or the transforming means being integrated in the antenna element/sub array or the electronic system, • parameters, being arranged to be optimised by using the optimisation process over the instantaneous bandwidth B (500) for maximizing the array processing gain of said array, and • the transforming means (100, 200, 150, Tr\-Trs) being arranged to affect the waveforms between at least all but one of the antenna elements and the sub arrays (£i-£w) and the electronic system (303, 1203) by use of the parameters obtained from the optimisation process over the instantaneous bandwidth B. 13. A wide band antenna system according to claim 1 2 , c h a r a c t e r i z ed in that the parameters are weighting coefficients being arranged to be organized in a weighting matrix comprising A'^ rows, one row for each transforming means, each row having M weighting coefficients, and that the weighting matrix is arranged to be optimised by using the optimisation process over the instantaneous bandwidth B (500) for maximizing the array processing gain of said array, each weighting coefficient in the NxM vyeighting matrix being defined as a parameter, M being a number corresponding to the number of spectral components. 14. A wideband antenna system according to claim 12 or 13, c h a r a c t e r i z e d in that the wideband antenna system comprises: 62 • a wideband array antenna having an array of at least two antenna elements/sub arrays or • a main antenna and an a wideband auxiliary antenna, the auxiliary wideband antenna being a single antenna element or an array of antenna elements/sub arrays. 15. A wideband antenna system according to any one of claims 12 - 14, c h a r a c t e r i z e d in that the transforming means, (100, 200, 150, Tn-Trfj) are arranged to be inserted between all of the antenna elements or sub arrays {E\-EN) in the wideband array antenna and the electronic system (303, 1203) and between all of the antenna elements or sub arrays in the wideband auxiliary antenna and the electronic system (303, 1203) or the transforming means being arranged to be integrated in the antenna element/sub arrays or in the electronic system. 16. A wideband antenna system according to any one of claims 12 - 15, c h a r a c t e r i z e d in that the parameters in the weighting matrix arranged to affect the waveforms between antenna elements/sub arrays are: • the weighting coefficients of a weighting matrix ff arranged to be obtained from the optimisation process over the instantaneous bandwidth B for M spectral components for each of the transforming means, thus resulting in a W-matrix having M columns and A^ rows, N being equal to the number of antenna elements and sub arrays or • the weighting coefficients of a corresponding weighting matrix w arranged to be obtained from the optimisation process over the instantaneous bandwidth B in the time domain , each row being the Inverse Fourier transformation of the corresponding row in the fVmatrix. 17. A wideband antenna system according to any one of claims 12-16, c h a r a c t e r i z e d in that the optimisation process over the instantaneous 63 bandwidth B is arranged to estimate the H'-matrix resulting in the maximum Normalized Array Processing Gain, NAPG, for a known Main Beam direction, NAPGMB, for the wideband array antenna or the wideband auxiliary antenna combined with a main antenna. 18. A wideband antenna system according to claim 17, c h a r a c t e r i z e d in that the NAPGMB. is arranged to be maximized by an arrangement to calculate a new w-matrix, Wr^w by continuously adding a scalar step As multiplied with a C-matrix to an old w-matrix Wou until the ratio: ANAPGMB= INAPGMB(W„,„,)| / I NAPGMB(W<,W) I has converged towards unity where the scalar "step length" As is a small adjustable value and where the (7-matrix includes all partial derivatives of NAPGMB with respect to the continuously updated w„e,r matrix. 19. A wideband antenna system according to any one of the claims 12 - 18, c h a r a c t e r i z e d in that an arrangement for achieving estimation of interference source parameters comprises means for performing an evaluation process to: • estimate Antenna Patterns, AP:s, for at least the frequencies corresponding to the M spectral components, • locate frequency stable minima in the Antenna Patterns, AP:s, giving the number of interference sources and the direction to these sources and • evaluate attenuation of the Antenna Patterns, AP:s, as a function of frequency in the frequency stable minima directions, giving the bandwidth of the interference sources. 64 20. A wideband antenna system according to claim 19, c h a r a c t e r i z e d in that: • the Antenna Pattern, AP. is arranged to be estimated for each of the frequencies corresponding to the M spectral components and for each frequency right between each pair of consecutive such frequencies for all directions of interest, • for each direction of interest a ratio R is arranged to be calculated, having a high value for interference directions and considerably lower values in non-interference directions, • the ratio R is arranged to be compared with a threshold, chosen to a suitable level related to the maximum value of the ratio R • the number of crossings of the ratio R defines the number of interference sources, • the direction to the interference source/s is defined by the direction/s corresponding to the crossing/s, • the Antenna Pattern, AP, is arranged to be calculated for each of the frequencies corresponding to the M spectral components in the directions of the crossings and • the bandwidth of the interference source is given by means for evaluating the Antenna pattern, AP, in the direction of the crossings as a function of frequency. 21. A wideband antenna system according to any one of claims 12-20, c h a r a c t e r i z e d in that a JRC module (1210) is arranged to receive an input comprising the parameters affecting the waveforms via an input connection (1208) from the electronic system (1203) or via a separate connection to the transforming means, the JRC module comprising means for performing the evaluation process for estimating the interference parameters and the JRC module (1210) is arranged to output the result of the estimation via an output connection (1209) to the electronic system (1203). 65 22. A wideband antenna system according to claim 2 1 , c h a r a c t e r i z ed in that the parameters arranged to affect the waveforms comprises the weighting coefficients in the w-matrix or the ff-matrix. 23. A wideband antenna system according to claims 21 or 22, c h a r a c t e r i z e d in that the JRC-module (1210) is incorporated in the electronic system (1203). or any computer available on a platform supporting the electronic system (1203) or connected to the platform via suitable communication facilities.