EP1472758A2

EP1472758A2 - Radio communication device and printed board comprising at least one current-conducting correction element

Info

Publication number: EP1472758A2
Application number: EP03708013A
Authority: EP
Inventors: Martin OELSCHLÄGER; Thorsten Kowalski; Michael Schreiber; Martin Weinberger; Stefan Huber
Original assignee: Siemens AG
Current assignee: Qualcomm Inc
Priority date: 2002-02-06
Filing date: 2003-02-03
Publication date: 2004-11-03
Also published as: AU2003212193A1; CN1628398B; JP2005522063A; CN1628398A; KR20040081190A; TW200303168A; US7151955B2; US20050159195A1; DE10204877A1; WO2003067702A2; TW589933B; WO2003067702A3

Abstract

The invention relates to a radio communication device (MP) which is characterized in that at least one additional, current-conducting correction element (ZV1) is connected to the printed board (LP) and configured in such a manner that a targeted, fictive current path elongation (WV) is brought about for an electric current (I(X)) possibly induced on the printed board (LP) by electromagnetic radio fields of the antenna (AT1) while the defined longitudinal and traverse dimensions of the printed board (LP) remain substantially unchanged.

Description

description

Radio communication device and printed circuit board with at least one electrically conductive correction element

The invention relates to a radio communication device with at least one printed circuit board accommodated in a housing of predetermined longitudinal and transverse dimensions, and with at least one antenna for emitting and / or receiving electromagnetic radio radiation fields, which is coupled to this printed circuit board.

Due to the power radiation from radio communication devices, in particular from mobile devices or cordless phones such as According to the DECT standard (Digital Enhanced Cordless Telecommunications), a certain proportion of the power of the electromagnetic radio radiation fields is usually also radiated into the human body. In particular, when the radio communication device is properly applied to the head of the respective user, organic tissue in the head can be subjected to an impermissibly high load. For this reason, limit values for the thermal power absorption for organic tissue in humans have been set. The so-called SAR value (= Specific Absorption Rate) is used as a specific measurement criterion for which radiation exposure the respective user is actually exposed to. This specifies the specific absorption rfce in watts per kilogram with which a predeterminable 'tissue volume range is heated.

The object of the invention is to show a way in which a radio communication device can be set in an improved, controlled manner with regard to its electromagnetic radiation characteristic. This object is achieved in a radio communication device of the type mentioned at the outset by coupling at least one additional, current-conducting correction element to the circuit board in this way. pelt and is designed that for an electrical current caused on the printed circuit board by electromagnetic radio radiation fields of the antenna, a targeted, fictitious current path extension is effected while at the same time largely maintaining the specified longitudinal and transverse dimensions of the printed circuit board.

In this way, in a controllable way, the local distribution of the resulting electrical current on the printed circuit board is improved.

The extension of the current path on the printed circuit board with the aid of the additional, current-conducting correction element makes it possible in particular to influence the local current distribution there in such a way that any local maximum of the electrical current or a related magnetic field is shifted to a less critical device area and / or can be reduced. In particular, it is advantageously possible to make inadmissibly strong "hot spots", ie tissue volume areas of higher SAR values compared to tissue volume areas of lower SAR values, and thus local local fluctuations in the thermal load of tissue volume areas - such as in the head area of the respective user when the radio communication device according to the invention is used as intended - to be reduced or even largely avoided. The SAR distribution can be made by at least one such additional correction element as a whole, at least more uniform or homogeneous compared to the SAR distribution of the same printed circuit board without a correction element. In addition, an improvement in the antenna impedance matching of the respective radio communication device and thus also an improved power radiation can be achieved in an advantageous manner, which is particularly advantageous with small, relatively compact device dimensions. Other developments of the invention are set forth in the claims Unteran ^¬.

The invention and its developments are explained in more detail below with reference to drawings.

Show it:

FIG. 1 shows a schematic representation of the printed circuit board and the radio antenna of a conventional mobile radio device coupled to it,

FIG. 2 shows a schematic representation of the local distribution of the electrical current effective for the SAR effect, which approximately flows during operation of the mobile radio device along the longitudinal extent of the printed circuit board of FIG. 1,

FIG. 3 shows schematically in a spatial representation a printed circuit board for a radio communication device, to which, in addition to the printed circuit board of FIG. 1, a correction element that extends the current path according to the invention is coupled,

FIG. 4 shows the local distribution of the electrical current flow along the longitudinal extent of the printed circuit board from FIG. 3 with the additionally coupled, current path-extending correction element,

Figures 5 with 7 in a schematic representation of further exemplary embodiments of correction elements according to the invention, each of which Printed circuit board of a radio communication device are coupled,

FIGS. 8, 9 each show the current flow profile along the longitudinal extent of the printed circuit board from

1 without and with a further, modified, current path-extending additional element,

FIG. 10 shows a schematic representation of a radio communication device according to the invention with a printed circuit board and with the additional, current path-extending correction element according to FIG. 9 when used as intended on the head of a user, and

Figures 11, 12 in schematic representation one each

Printed circuit board with a modified correction element coupled according to the invention for virtual current path extension.

Elements with the same function and mode of operation are provided with the same reference numerals in FIGS. 1 with 12.

Figure 1 shows schematically in a spatial representation a printed circuit board LP, as it is usually housed in the housing of a radio communication device such as a mobile phone or cordless phone. In FIG. 10, for example, such a printed circuit board LP is provided in the interior of the housing GH of a mobile radio device MP, which is shown schematically there in side view when it is used as intended on the head HE of a user. The mobile radio device MP is preferably designed as a mobile radio telephone, which in particular according to the GSM (Global System for Mobile Communicati- ons), IS95, IS136, IS2000, DCS1900, GPRS (General Packet and Radio Service), EDGE (Enhanced Data Rates for GSM Evolution), UMTS (Universal Mobile Telecommunication System) standard. It is preferably dimensioned such that it is portable for a user and can therefore be with the user at changing locations in the radio cells of such radio communication systems. In addition or independently of the voice transmission or telephoning function of such a mobile radio device, it may also perform the function of transmitting other messages, such as data, images, fax messages, emails, or the like.

Furthermore, a printed circuit board according to FIG. 1 can also be integrated in the housing of another cordless telephone which processes its communication traffic by radio with a local base station or other subscriber devices. Such cordless telephones currently preferably work according to the so-called DECT (Digital Enhanced Cordless Telecommunications) or Bluetooth standard.

Spatially, the printed circuit board LP of FIG. 1 essentially has a flat, rectangular cuboid shape, ie its four side edges SRL, SRR, SRO, SRU, when put together, form the outer contour of a rectangle, the longitudinal extent of which is greater than its width. Their spatial geometric relationships are illustrated by the fact that the coordinates X, Y and Z of a Cartesian coordinate system are also shown in FIG. 1. The X coordinate extends along the long sides SRL, SRR of the printed circuit board LP, while the Y direction runs parallel to the broad sides SRO, SRU of the printed circuit board LP. The component placement area BF of the printed circuit board LP is therefore essentially in the X, Y plane. The Z direction is assigned to the height or thickness H of the printed circuit board LP with its various components such as high-frequency module HB1 and evaluation / control module HB2. The rectangular shape of the printed circuit board is preferably suitable for installation in a flat, essentially cuboid housing. Of course, the printed circuit board can also have other outer contours, which as a rule are expediently chosen to be adapted to the respective geometrical shape of the housing of the respective radio communication device.

For receiving and / or transmitting radio signals, the printed circuit board LP of FIG. 1 has a high-frequency module HB1 with a coupled antenna ATI in the area of the upper half of its longitudinal extent. For the sake of drawing simplicity, the high-frequency assembly HB1 is only indicated by a dashed frame. With the aid of the ATI transmission / reception antenna, electromagnetic radio waves can be emitted into the radio space and / or detected coming from it. The transmit / receive antenna ATI is connected to the high-frequency module HBl for energy supply, in particular power supply, and radio signal control via an electrical contact line COA ("hot conductor"). At the same time, it contacts at least one ground plane via a second electrical line KS1 (* cold conductor ") ground ") on the printed circuit board LP. Such a ground surface can be formed, for example, by the metallic housing cover or the shielding cover of the high-frequency module HB1 or by a conductive layer that covers the entire surface on the upper or lower side of the printed circuit board, or as an intermediate layer in the The contact lines are expediently designed in such a way that the antenna ATI is attached to the printed circuit board LP with sufficient mechanical stability and thus maintains its predetermined position or position as permanently as possible n be shaped like a web, so that they each take over, individually or together, a type of flange function for mechanically fixing the antenna ATI to the printed circuit board. In the exemplary embodiment of FIG. 1, the antenna ATI is coupled mechanically and electrically to the upper end face or broad side SRO of the printed circuit board LP with the aid of these contact lines COA, KS1. The antenna ATI is designed as a planar antenna. It has an approximately rectangular shape. It is positioned with the help of the mechanical connecting webs COA, KS1, starting from the upper side edge SRO of the printed circuit board LP, into a spatial area which is enclosed by the four side edges SRL, SRR, SRO, SRU along the surface normal in the Z direction. The imaginary orthogonal projection of the antenna onto the component placement area of the printed circuit board LP thus lies essentially within the boundary area BF spanned by the side edges SRL, SRR, SRO, SRU of the printed circuit board LP. In other words, this means that the antenna ATI does not extend beyond the four side edges of the component placement area BF of the printed circuit board LP, ie the board surface is neither extended nor widened by the coupled antenna. The antenna ATI is inclined or bent in the direction of the printed circuit board LP with the aid of the connecting webs such that it lies like a further layer above and / or below the plane of the printed circuit board LP within the space area delimited by its four side edges. This antenna arrangement allows particularly compact or small device dimensions to be realized in an advantageous manner.

In the second, lower half of the printed circuit board LP of FIG. 1, one or more further electrical assemblies are accommodated, which for the sake of simplicity of the drawing are also only indicated with a dashed frame and provided with the reference symbol HB2. These serve to control the input and / or output elements of the mobile radio device MP, such as its keyboard, display, loudspeaker, etc., and to carry out the signal processing of the radio signals received by means of the high-frequency module HB1 and / or to be transmitted via the latter. In the case of such a printed circuit board with coupled antenna, there is an associated, local total current distribution in the X direction, ie viewed along the longitudinal extent of the printed circuit board, as is shown schematically in FIG. 2. The electrically effective total current I (X) is plotted along the abscissa, which adds up or integrates in total at each longitudinal position position X of the printed circuit board LP over its total cross-sectional width B in the X and thus longitudinal direction of the board. It is assumed that the cause of this electrical current flow with a preferred direction in the X direction is H fields, ie magnetic fields, which arise locally in the vicinity of the antenna ATI during its operation.

In FIG. 2, the origin of the X axis is assigned to the lower side edge SRU of the printed circuit board LP from FIG. 1, while the upper side edge SRO corresponds to the longitudinal extent value X = L. In the area of the electrical contact point COA between the high-frequency module HB1 and the antenna ATI, the antenna ATI flows at the longitudinal point X = L of the supply or base point current FSI ≠ 0. Because the HB1 high-frequency module feeds a defined supply current FSI into the base of the antenna ATI. In contrast, the current flow in the longitudinal direction of the printed circuit board LP is interrupted at its lower free end by the edge limitation there, i.e. I (X) = 0 largely applies on the end face opposite the antenna ATI. In the preferred use of a so-called λ / 4 antenna, however, the electrical field has a maximum at the lower side edge or at the free end SRU opposite the antenna. Due to the geometric relationships of the printed circuit board LP in the form of an elongated rectangle, along the central longitudinal axis ML occurs approximately in the center MI of the printed circuit board LP, i.e. that is, in the area of the intersection their diagonals, in the case of the resultant being integrated over the cross-section width B, respectively

Total current I (X) has the largest effective current amplitude for the SAR effect. Over the transverse direction Y of the printed circuit board because of skin and other current shift effects, the component of the current flow strength in the X direction in the region along the two longitudinal edges SRL, SRR is higher than along the center line ML; the current intensity distribution at the longitudinal edges SRL, SRR is essentially axially symmetrical to the central longitudinal axis ML. This current distribution leads to an H field effective or resulting for the SAR effect, to which the total current I (X) - as shown in FIG. 2 - with a main concentration along the central longitudinal axis ML can be assigned. The maximum of the effective current amplitude at the longitudinal point X = MI is denoted by IM in FIG. 2.

In such a coupled structure with at least one antenna and at least one electrically conductive printed circuit board connected to it, there is a locally inhomogeneous current distribution on the printed circuit board surface, i.e. the total current flow rate that becomes effective for the SAR effect fluctuates locally.

A measurement method, which is described in detail in the European standard proposal EN50361, is preferably used to determine the SAR values of mobile radio devices or, in general terms, of radio communication devices as a measure of the thermal heating of a specific tissue volume area. It searches for the location of the highest thermal load of the respective user. The SAR value then results from an integration over a certain standardized tissue volume where the mobile radio device MP is placed on the head HE of the respective user when it is used as intended (cf. FIG. 10).

Extensive tests with an electromagnetic measuring probe in a model head, which is filled with a simulation solution, have now shown that the heating of the organic tissue fluctuates or varies locally, that is, a local distribution with at least one maximum and / or minimum. has. This locally varying field concentration seems to be due in particular to a corresponding local total current distribution such as I (X) from FIG. 2 on the printed circuit board LP. Such an electrical total current I (X) preferably flows on the printed circuit board LP along its longitudinal extent if the transmitting and / or receiving antenna, such as ATI from FIG. 1, is designed as a λ / 4 antenna, and one together with the printed circuit board LP Radiation dipole forms. In a first approximation, the printed circuit board acts as a kind of λ / 4 antenna that complements the ATI antenna. FIG. 2 shows the local distribution I (X) of the current flow effective for the SAR effect along the longitudinal extent X of the printed circuit board LP. The near range is the local range that is below the distance 2 D ² / λ (λ is the wavelength; D is the length of the device). For example, in the GSM radio network with a frequency range between 880 and 960 MHz (center frequency 900 MHz), the wavelength λ is approximately 35 cm. In the PCN (Private Commercial Network) (E-Netz) with a frequency band between 1710 and 1880 MHz, the wavelength is approximately 17 cm. In a UMTS radio communication system with a frequency transmission range between 1920 and 2170 MHz, the wavelength λ is approximately 15 cm. While the penetration depth of the electromagnetic near field of about 6 cm is to be expected in the GSM radio system due to the local power distribution on the printed circuit board, and about 5 cm for the PCN network, the penetration depth of the near field for a UMTS mobile radio device is based on the local area Current distribution on the main board around 2 to 4 cm. The lower the local penetration depth into the tissue, the higher the measured SAR value can be with the same assumed transmission power of the antenna, since the higher the electromagnetic field density per given tissue volume, the greater the current that flows and thus a higher field concentration is caused. It is now desirable to adjust electromagnetic radiation fields, in particular the H field in the close range of the respective radio communication device, and / or electrical currents resulting from them, in a more controlled manner with regard to their local distribution.

FIG. 3 shows schematically a first exemplary embodiment of a correction element according to the invention for virtually extending the current path on the printed circuit board LP of FIG. 1. This first correction element is designated KV1 in FIG. 3. It is attached to the narrower - here lower - side edge SRU of the printed circuit board LP, which is opposite the other, narrower - here upper - side edge SRO with the coupling of the antenna ATI. It is essentially U-shaped. It has a web element KV1 or KV2 on both the upper side and the lower side of the printed circuit board LP, which is essentially vertical, ie along the surface normal Z of the upper and lower side of the printed circuit board LP. These web elements KV1, KV2 are preferably mounted symmetrically with respect to the printed circuit board LP on its lower end face SRU. They preferably run essentially along the entire width B of the printed circuit board LP along its lower side edge SRU. This provides a largely ideal coupling of the web elements in terms of shaft resistance. On each cross bar element KV1 or KV2, in turn, an essentially flat, second bar element PST1 or PST2 is attached in such a way that it runs essentially parallel to the top and bottom of the printed circuit board LP (= printed circuit board assembly level) and within the through the four Side edges of the circuit board limited space area is positioned. The second web elements PST1, PST2 are therefore essentially perpendicular to the cross webs KV1, KV2 of the width ZVB along the Z axis. In this way, the correction element KV1 is coupled both mechanically and electrically to the printed circuit board LP. All in all, due to its U-profile shape, the correction element ZV1 sits roof-like on that end of the printed circuit board LP which is opposite the opposite side of the printed circuit board SRO with the antenna coupling. This roof-like covering of the printed circuit board LP by the correction element KV1 forms together with the antenna ATI at the other end of the printed circuit board LP a kind of roof capacitance. This overall structure with the printed circuit board LP, the antenna ATI coupled to it and the correction element ZV1 also connected to the printed circuit board represents a kind of short rod antenna from the electrical point of view, which has plate-shaped electrodes or capacitor surfaces in the form of the antenna ATI and at its ends the correction element ZVl. The effect of the correction element ZV1 as additional end capacitance, however, electrically extends the printed circuit board LP, ie virtually, electrically, so that a total current effective for the SAR effect on the printed circuit board LP, possibly caused by electromagnetic radio radiation fields of the antenna ATI I (X) can provide a targeted electrical current path extension. This is because any electrical sum current flowing along the longitudinal extent of the printed circuit board LP - and here in the exemplary embodiment of FIG. 3 in the X direction - can now additionally flow onto the expansion surface of the correction element ZVl, which starts from the lower edge SRU of the printed circuit board LP is folded over and / or under the space area delimited by the four side edges of the printed circuit board LP. Tests have shown that in order to achieve a specific, desired extension of the current path specified by the original longitudinal extension, such as L of the printed circuit board such as, for example, the path length additionally provided by the respective correction element from its coupling region to the printed circuit board to its front end is decisively determined.

In FIG. 3, the correction element ZV1 ensures a path extension by ZVB in each case in the Z direction on account of the respective cross web KVl, KV2 and in total by the further path length ZVL in the X direction through the respective web element PST1 or PST2. The first approximation, in particular, is dominant for the electrical path extension, in particular the mechanical routing of the respective correction element, starting from its coupling region on the printed circuit board LP to its front end, measured in the imaginary, unfolded, that is to say flat, state of the correction element. The correction element continues, so to speak, the longitudinal extension of the printed circuit board, but not in the original position plane of the printed circuit board, but into a spatial area that is delimited by the four side edges of the printed circuit board and lies above and / or below the boundary surface BF of the printed circuit board. In FIG. 3, the achievable path length is given by the total folding length of the correction element ZV1 in the X and Z directions, that is to say in total by the path sections ZVB and ZVL. An extension in a real test by 30 percent advantageously leads to a reduction in the SAR value by approximately 20 percent.

FIG. 4 schematically shows the local current distribution along the longitudinal extent of the printed circuit board from FIG. 3, ie in the X direction, when the additional correction element ZV1 is attached to the printed circuit board LP. Compared to the printed circuit board LP of FIG. 1 without a correction element, on which a resulting current maximum IM occurs approximately in the middle of the longitudinal extent at X = MI, the effective current level now flattens out at the point X = MI, ie in the central region MI Printed circuit board LP to the value I (X = MI) = IMD <IM. In particular, there is a homogenization of the local current distribution on the printed circuit board LP in the X direction. Since a current flow is now also caused at the lower end of the printed circuit board LP by the additional coupling of the correction element ZVl, here with I (X = 0) = ID, the current flow shifts or extends to the outer, open end of the Correction element ZVl out. With the help of the correction element ZVl can thus be defined Set a current level distribution I (X) between X = 0 to L along the length of the printed circuit board, which compared to a printed circuit board according to FIG. 1 without correction element viewed from one end to the other end of the printed circuit board has a more homogeneous, that is to say approximately constant, current density. FIG. 4 additionally shows the fictitious or virtual current path extension WV, which is measured with the correction element ZVl from the coupling area on the lower end face SRU (X = 0) of the printed circuit board LP to the outer, open end (X = L) of the correction element ZVl results. The current flow is only interrupted at the open end of the additional element ZV1, so that the total current level is essentially equal to 0 only there. The total current level I (X) along the extension path WV is additionally shown in dash-dotted lines in FIG. It is formed by interpolating the values of the current level curve between the upper and lower end face of the printed circuit board LP, ie between X = 0 and X = L, and the current level value of 0 amperes at the free or open end of the correction element.

In a first approximation, the virtual, electrical current path extension such as WV, which results from the additional coupling of the correction element such as ZVl along the longitudinal extent, here in the exemplary embodiment in the X direction, results in particular from the sum of the path lengths of the correction element in the Z. -, X-plane determined. In addition or independently of this, the total area formed by the respective correction element can also influence the resulting total current length. This is because the larger the provided area of the correction element, the greater the capacitive charging possibility and thus the possible current harmonization on the printed circuit board. It is also conceivable to split the current distribution into two or more maxi a on the circuit board. The correction element such as ZV1 can expediently be formed in one piece. For this purpose, it can preferably be produced by bending or folding from an originally flat, current-conducting element.

As a respective correction element such as ZVl is preferably at least one electrically conductive element, advantageously a single or multi-layer, electrically conductive sheet, coating element, a single or multi-layer film, and / or another electrically conductive surface element or structural element. If necessary, it may also be sufficient to provide one or more electrically conductive wires as the correction element.

If necessary, a virtual current path extension along the longitudinal extent of the printed circuit board can also already be brought about by a correction element which is not coupled over the entire broad side of the printed circuit board LP to the end face opposite the antenna, but rather is formed by a strip-shaped, electrically conductive element, the width of which is considerably narrower is chosen as the width 'of the printed circuit board LP. Such a correction element is shown schematically in FIG. 5 in a spatial representation. It is labeled ZV2. So that the greatest possible current path extension can be fictitiously provided in the X direction, that is to say along the longitudinal extent of the printed circuit board LP, the strip-shaped correction element ZV2 is meandering in the X, Y plane. It is mechanically and / or electrically connected to the printed circuit board LP in the area of its lower edge on the front side, which is opposite the upper edge on the front side with a stub antenna AT2 which projects there and projects outwards. The correction element ZV2 can be coupled to the printed circuit board LP in particular in a simple manner by bending or bending over a partial section of the board ground plane. The meandering correction element ZV2 is preferably along an end section by approximately 90 ° with respect to its other essentially flat surface. kinked or bent. This coupling section is designated KV2 in FIG. The correction element ZV2 extends with its electrically conductive, essentially planar surface for the most part in a plane that is essentially parallel to the plane of the printed circuit board LP. A desired extension of the current path can be chosen by selecting the meandering shape accordingly, ie by selecting the number of meandering windings and / or selecting the length of those sections of the correction element ZV2 which essentially run in the longitudinal direction X or transverse to it in the Y direction of the printed circuit board LP be controlled in a controlled manner.

Generally speaking, a desired current path extension for a printed circuit board of a given length and width to be maintained can be provided in a targeted manner in that one or more correction elements are additionally coupled to the printed circuit board in such a way that this correction element only extends into a space above and / or extends below the circuit board, which is limited by the side edges of the circuit board. This results in a multi-layer structure, i.e. the printed circuit board and the respective correction element are, so to speak, stacked on top of one another. The correction element can in particular be one or more folds in one or more

Have levels that lie within the plane delimited by the side edges of the printed circuit board and are arranged at a height distance from the latter. In this way, the printed circuit board is not extended or widened in its position level, i.e. their originally specified dimensions are largely maintained with regard to their originally specified length and width.

For virtual extension of the mass, it may be expedient to design a partial area of the ground surface of the circuit board itself in such a way that an additional lengthening element is created. Such is shown in FIG Correction element ZV6 is an integral part of the board ground area of a printed circuit board LP * with an originally rectangular outer contour. A part of the ground area of the printed circuit board LP * on the front side SRU of the printed circuit board opposite the antenna ATI is designed separately from the latter in the same position level that it acts as an extension of the current path. The correction element ZV6 has its meandering shape due to successive 90 ° bends or rectangular zigzag bends of web sections. This meandering correction element KV6 can be produced in particular by punching out or cutting out the originally rectangular printed circuit board LP from FIG. The correction element ZV6 is preferably provided in a corner region of the lower face of the circuit board SRU, which is arranged obliquely, in particular diagonally offset, to the antenna coupling in the corner region of the upper, opposite end face SRO. Because this largely diagonal path between the antenna ATI and the free end FE of the correction element ZV6 is the greatest possible virtual path extension for the in terms of

SAR effect effective total current provided on the available board area with the same predetermined, rectangular outer contour.

The current path can be set in a controlled manner by folding the respective correction element within the printed circuit board assembly area and / or above the printed circuit board top and / or printed circuit board underside. Through a meandering shape, ie through a shaping of the correction element, in which a partial section with extension in the longitudinal direction of the printed circuit board alternates with a section transverse, in particular orthogonal, to the longitudinal extension of the printed circuit board, and in each case two such successive partial sections unite Include non-zero angles between them, in particular offset by approximately 90 °, the length of the correction element in the X direction can be relatively short hold. Because of the zigzag shape, more run length can be achieved for the electric current compared to a correction element with a straight strip shape. The maximum possible current path on the printed circuit board LP * from FIG. 11 begins in the area of the antenna ATI and ends at the free end FE of the correction element ZV6 after passing through its meandering turns.

If the circuit board LP has an antenna protruding outwards along its longitudinal extension in a corner area of its front end, e.g. Coupled AT2 in Figure 5, it is expedient to mechanically and electrically attach the correction element relative to the antenna on the printed circuit board in such a way that it provides a current path extension essentially along the dash-dotted diagonals DIG from the corner area of the antenna to the diametrically opposite corner area of the correction element ZV2 (see Figure 5). In Figure 5, this diagonal DIG is also shown in dash-dotted lines. It describes the current path, which an electrical current on an essentially rectangular printed circuit board such as LP of Figure 5 can travel a maximum. The antenna AT2 is designed in FIG. 5 as a rod antenna projecting outwards. Tests have shown that this diagonally offset arrangement of the antenna AT2 and the correction element ZV2 enables the current path to be effectively and virtually extended. At the same time, the length of the correction element in the longitudinal direction of the circuit board can be largely compact, i.e. be kept relatively short. Such a meandering correction element preferably has a longitudinal extent between 1 cm and 4 cm.

Possibly. it can also be expedient to arrange the respective correction element laterally in a spatial area on the boundary surface BF spanned by the side edges such as SRL, SRR, SRO, SRU of the printed circuit board such as LP of FIG. A correction element is shown in FIG. The ZV7 is coupled to the right-hand side SRR in the area of the corner ECK, which is approximately diagonally opposite the antenna ATI. This correction element ZV7 has a first sub-element WT, which is fixed essentially orthogonally with respect to the boundary surface BF on the longitudinal side edge SRR. At its upwardly projecting end sits a second sub-element DAC, which is bent approximately 90 ° with respect to the first sub-element WT and protrudes into the boundary surface, or forms its edge. It is thus arranged at a vertical distance from the printed circuit board assembly surface and, as a roof-like partial cover, runs essentially parallel to the latter. Of course, the first and second sub-elements WT, DAC can be formed as a single component, ie in one piece. For example, the hook-like or elbow-type correction element KV7 can be produced, for example, by bending an originally planar, electrically conductive element such as copper sheet.

For a reduction of the SAR effect or displacement of undesirable ^w hot spots "in non-critical areas of the machine, other geometrical shapes of correction elements may optionally be useful as long as the respective correction element can be coupled such to the printed circuit board so that its imaginary orthogonal projection of the Bauelementbestü- ckungsfläche respect of the printed circuit board LP essentially lies within the boundary surface BF spanned by the side edges SRL, SRR, SRO, SRU of the printed circuit board LP. It may therefore already be sufficient to omit the second partial element DAC and only on one or more partial sections of one or several side edges to let the first partial element WT protrude upwards with a 90 ° inclusion angle or less with respect to the circuit board area, in particular such a correction element can be formed by at least one side edge of the printed circuit board along a partial section or is bent or flanged accordingly over its entire length. It is particularly expedient that broadside - here in FIG. 12 SRU - to partially or completely pull up or bend, which is opposite to the front side of the printed circuit board with the antenna coupling.

FIG. 6 shows a further example of an artificial current path extension without widening or extending the printed circuit board in its position plane itself. A so-called PIFA antenna (Planar Inverted F antenna) PIF is coupled to the printed circuit board LP of FIG. 6 via a current supply point SS. There it is fed with an electric current. The PIFA antenna PIF is arranged at a distance from the plane of the printed circuit board LP. It is essentially planar, that is to say formed flat and aligned such that it lies essentially parallel to the position plane of the printed circuit board LP. The PIFA antenna is attached in the area of the upper end SRO of the printed circuit board LP. So that electrical radio radiation fields can be generated and decoupled into free space, a ground plane ZV3 is arranged between the printed circuit board LP and the PIFA antenna PIF. This ground plane ZV3 extends essentially parallel to the plane of the printed circuit board and the PIFA antenna. It has a transverse distance to the printed circuit board LP, ie a height D1 (preferably greater than 1 mm), and a transverse distance D2 to the PIFA antenna. Electrical and / or magnetic fields are formed between the PIFA antenna and the ground plane ZV3 arranged at a transverse distance from it, which can be decoupled into the spatial area. The ground surface ZV3 is connected to the ground of the printed circuit board LP in the region of one of its front ends. This ground coupling is designated KV3 in FIG. 6. An artificial extension of the printed circuit board LP with regard to the available current path along its longitudinal extension can be provided in a simple manner by the length of the ground surface ZV3 of the PIFA antenna PIF, which is present anyway, being extended accordingly along the longitudinal extension of the printed circuit board LP. Since the PIFA antenna is arranged in two layers above the surface of the printed circuit board, Overall, a multi-layer structure, without the original circuit board size being increased in length and width, but is kept constant.

Figure 7 shows schematically in a spatial representation the circuit board LP of Figure 1 with a further correction element ZV4, which electrically extends the electrical current path along the longitudinal extent of the circuit board LP, ie here in the exemplary embodiment in the X direction along the long sides of the circuit board LP, without the change the original length and width of the circuit board. The correction element ZV4 is now formed in that an electrically conductive coating is provided on the power supply unit, in particular battery unit AK. Such a power supply unit is preferably designed to be rechargeable. It serves to supply the electrical components and conductor tracks on the printed circuit board LP with electrical current. For example, a metallization on the battery surface along an elongated rectangular strip can be provided as the electrically conductive coating ME. This metallization layer is connected to the printed circuit board LP via an electrical contact KV4. The electrical contact KV4 of the rectangular metallization path is preferably carried out in the region of the front end of the printed circuit board LP in order to achieve the longest possible run length for the current. The maximum run length provided for any current that may flow in the X direction extends from that end area of the printed circuit board LP in which the transmitting / receiving antenna AT3 is coupled to the opposite end where the correction element ZV4 is electrically coupled is, plus the strip length of the correction element in the longitudinal direction X. Here in the exemplary embodiment, the antenna AT3 is designed as a planar antenna or flat antenna. For this purpose, a slotted sheet or another electromagnetically conductive element is preferably used. The antenna AT3 can be shaped such that it functions both as a dual-band and as a multi-band antenna for transmitting and receiving electromagnetic radio waves of different frequency ranges. The antenna AT3 is supplied with current in the upper area of the printed circuit board LP via an electrical line SS. Another area of the flat antenna AT3 is connected to the ground of the printed circuit board LP via an electrical contact MK.

In addition, there is an electrically conductive track here

Length WV * provided along the metallization ME in the X direction of the battery unit AK, i.e. along the longitudinal extent of the printed circuit board LP. In total, the metallization ME on the battery unit AK has the effect that the printed circuit board LP of length L is additionally electrically virtually extended by the path length WV *. However, the original dimensions of the printed circuit board LP in terms of length and width remain constant, since the additional extension WV * is achieved in that the additional current path extending conductor track ME is provided in a plane above the printed circuit board area itself. The electrical connection or contacting of the metallization area ME to the mass of the printed circuit board LP can be produced, for example, via electrical wires, foils or other electrically conductive intermediate elements.

Here, in the exemplary embodiment in FIG. 7, the metallization ME is applied to the outer surface of the approximately cuboidal battery unit AK only on a partial surface of the outer surface of the battery unit AK. It can also be expedient to apply the metallization ME to the entire top of the battery unit AK. In particular, one or more or all of the battery surfaces can be partially or completely coated with such a conductive coating. FIGS. 8 and 9 each illustrate the desired shift of the so-called SAR hot spot, ie the local maximum in the local total current distribution along the longitudinal direction of the printed circuit board without and with a current-element-lengthening correction element. In FIG. 8, that is in the upper half of the figure The side view of the printed circuit board LP of the flat antenna AT3 in Figure 7. In the lower half of the figure, the local total current distribution I (X) that occurs during the operation of the mobile radio telephone is drawn in along the length of the board in the X direction, the X direction being the abscissa The flat antenna AT3 is electrically coupled at the left end of the printed circuit board LP to the latter via a power supply line SS and the ground contact MK. Since the antenna AT3 is actively supplied with current in the area of this front end of the printed circuit board LP, the left side edge of the circuit board LP d current flow greater than 0 amps. Towards the middle of the longitudinal extent of the printed circuit board LP of the total length X = L, the total current level at the point X = XM1 reaches a local maximum IM1. The total current density then increases in the direction of the end of the printed circuit board LP opposite the antenna AT3 until there is an interruption in the current flow at the point x = L on the right side edge, so that there is approximately I (X) = 0 A. Overall, there is a total current distribution SV (X) along the length of the printed circuit board, which has a local maximum at X = XM1 in the half of the printed circuit board assigned to the antenna.

If an additional electrically conductive correction element ZV5 is now electrically connected or coupled to the front end of the printed circuit board LP that is opposite the opposite, second front end region of the printed circuit board LP with the antenna coupling, then depending on the dimensions, shape, positioning and other material parameters (such as conductivity) of the correction element ZV5 at least the original shift the local local maximum along the longitudinal extent of the printed circuit board LP in the X direction. This is illustrated by the local current distribution SV * (X) in the lower half of FIG. 9. The X direction is plotted along the abscissa, while the total current density I (X) is assigned to the ordinate for each position X. In FIG. 9, the current-extending correction element ZV5 is formed, for example, by a wire element that is approximately rectangular in side view. The longer the extension of the wire element in the X direction above the surface of the circuit board is selected, the more the current path extension becomes noticeable through this additional conductor track. As a result, the local current maximum IM2 shifts in the X direction to the longitudinal point X = XM2> XML. This makes it possible to correct the originally existing, local distribution of the electrical total current flow on the printed circuit board that is effective for the SAR effect change that the current level maximum or the current level maxima are at least shifted into a less critical area of the device, or even an equalization of the current level distribution is effected. In addition to making the current curve more uniform, it is also possible to reduce the current maximum (s), so that IM2≤IM1 applies in general. Only then can the actual electromagnetic field distribution in the vicinity of the mobile radio device be set in a more controlled manner. In the present exemplary embodiment of FIG. 9, the current level maximum IM2 is shifted away from the antenna area along the X direction, that is to say the longitudinal extent of the printed circuit board LP, to be precise in an end area which is opposite the other end area of the printed circuit board LP with the antenna coupling. The reason for this targeted shifting measure is that, as a rule, the radio communication device in the area of the antenna coupling is assigned to the ear area of the respective user, while the other end of the radio communication device in the cheek area of the respective user User lies and has a larger gap or transverse distance from this.

FIG. 10 illustrates this effect of the displacement of the so-called SAR hot spot with the aid of the at least one correction element. There, the head HE of a user is drawn schematically in a front view, which uses a mobile radio device MP as intended and holds it against the cheek the upper Εncte- ^' .eles mobile device MP assigned to the ear EA of the user, because the loudspeaker of the mobile device MP is usually accommodated there, at the same time the high-frequency assembly of the printed circuit board LP with the transmitter is located inside the housing GH of the mobile device MP - / Receiving antenna such as AT3 from FIG. 9. The printed circuit board LP additionally has the current-path-extending correction element ZV5 in the lower front end region — its longitudinal extension, which faces away from the antenna region, as shown in FIG Figures 8 and 9 without and mi t Correction element shown in dash-dot lines. While in the case of a printed circuit board LP without a correction element, the local current level maximum lies approximately in the contact area AZ of the housing GH on the head HE of the respective user, the presence of the correction element ZV5 allows the local current maximum to be determined according to the local one

Current distribution curve SV * (X) shifted to the correction element ZV5 and thus brought further away from the support area to the lower end of the mobile device. Since, due to the curvature or curvature of the head shape of the respective user, the printed circuit board in the housing GH at the lower end generally protrudes from the cheek or cheek BA of the user with a gap, the maximum of the current distribution is thus at least in one area of the Housing GH shifted, which is less critical with regard to the generation of the SAR value. Because due to the transverse distance DB between the underside of the printed circuit board LP and the jaw BA of the user, a maximum of the current level distribution which may be present there can be wide become less effective. While the printed circuit board without correction element has the current level distribution SV (X) with a current maximum at a point on the printed circuit board which has the transverse distance DA from the jaw, the transverse distance on the printed circuit board LP with the correction element ZV5 is now determined according to the local current distribution SV * (X ) to a longitudinal point where the transverse distance between the printed circuit board and the cheek of the respective user is increased to the column distance DB> DA.

The shift of the originally existing local maximum on the printed circuit board into an area that has a larger column spacing DB from the cheek of the respective user than in the case without a correction element has the following effect on the fields that come into effect: a possible on the printed circuit board flowing current causes an electromagnetic power density PA in the area of the contact area AZ on the printed circuit board due to the correspondingly generated magnetic H field of PA = ZFD H ² , where ZFD is the characteristic impedance and H denotes the magnitude of the magnetic field strength. The power density of the magnetic field H now decreases inversely proportional to the square of the distance or the distance of its generation source due to the current flow. It therefore applies in the area of the support zone AZ: PA ~ 1 / DA ² . In the area of the lower half of the housing GH at the location of the shifted local current maximum, the following therefore applies accordingly to the power density of the H field generated by the current maximum: PB ~ 1 / DB ² . The relationship between the two power densities is as follows: PB / PA = DA ² / DB ² . If the current maximum is now shifted into an area of the printed circuit board which has approximately twice the transverse spacing or column spacing from the cheek of the respective user, so that DB = 2 DA, the power density PB takes up a fourth of the original power density at the original one Support zone AZ from. The power density in the area of the shifted current maximum of the current curve SV * (x) shows only a quarter of the power density at the jaw along the normal to the board surface as in the support zone AZ of the housing GH, where the printed circuit board is at a transverse distance DA from the cheek of each user is removed. This corresponds to a reduction in the effective energy power density of approx. 6 dB, since PB / PA = => 10 log PB / PA = 6 dB. If the original local SAR-effective current maximum is shifted with the aid of the correction element into a circuit board area which has approximately twice the transverse distance as originally to the head of the respective user, this results not only in a halving but in a reduction to a quarter of the originally effective Leis - density.

In addition, it may be expedient if necessary to give the housing GH of the radio communication device MP such a shape that, in the region of the shifted current level maximum, there is also a convex curve outward away from the head HE

Has inner surface. As a result, the transverse axial distance to the head along the normal of the board surface can be further increased, so that where the shifted current maximum occurs on the printed circuit board, an additional distance to the head of the user is still achieved.

The actual longitudinal extent of the respective correction element in the unfolded, maximally extended state is preferably selected between 10% and 90%, in particular between 10% and 50% of the maximum dimension length of the printed circuit board. The correction element thus preferably has a longitudinal extent such that for an electrical current possibly flowing along the longitudinal direction of the printed circuit board there is a fictitious path extension of 1.1 times to 1.5 times the original longitudinal extension of the printed circuit board. In the case of a rectangular printed circuit board approximately 9 cm long and 4 cm wide, the longitudinal extension of the correction elements in the flat, unfolded state are expediently chosen between 1 and 8 cm, preferably between 1 and 5 cm.

In particular, the correction element can also be designed with multiple kinks, angled or helical (coiled) curves. If necessary, it can be composed of partial lengths at different altitudes.

It can advantageously be coupled to the printed circuit board not only galvanically, but additionally or independently of it with the same function and mode of operation with regard to the effect of extending the current path, also capacitively, inductively and / or radiated.

In summary, at least one additional, electrically conductive correction element is coupled and designed to the respective printed circuit board in such a way that for an electrical one caused on the printed circuit board by electromagnetic radio radiation fields of the antenna

Current is a targeted, fictitious or virtual current path extension while largely maintaining the specified longitudinal and transverse dimensions of the circuit board. This makes it possible to adjust electromagnetic radiation fields, in particular the H field in the close range, of the respective radio communication device, and / or electrical currents resulting therefrom in a more controlled manner with regard to their local distribution. For example, any local maximum of the electrical current effective for the SAR effect can be shifted, reduced, and / or distributed over several lower extremes in a defined manner on the printed circuit board.

Measurements have shown that the reason for a relatively high SAR value of a mobile radio device is, in particular, inhomogeneities in the current distribution resulting on the printed circuit board. The fact that at least one current-conducting capable correction element is coupled to the printed circuit board in a space area that is delimited by the side edges of the printed circuit board, with the same size and dimensions of the printed circuit board in terms of length and width, at least a displacement of the at least one local current level maximum into less critical housing areas, and / or a largely homogeneous field distribution along the longitudinal extent of the radio communication device according to the invention is achieved. As a result, the measurable SAR value can be further reduced in an advantageous manner.

The additional correction element is preferably coupled to the printed circuit board and designed in such a way that a fictitious current path extension is effected for the electrical current, which leads to a desired SAR value reduction (specific absorption rate) in the area surrounding the printed circuit board.

In particular, the respective additional, electrically conductive correction element is coupled to the printed circuit board in such a way that its imaginary orthogonal projection with respect to the component mounting area of the printed circuit board lies essentially within a boundary area spanned by the side edges of the printed circuit board.

For this purpose, the electrically conductive correction element is preferably arranged only in a spatial area inside, and / or above, and / or below, and / or laterally on the boundary surface spanned by the side edges of the printed circuit board. Characterized in that the correction element forms a kind of multilayer structure together with the circuit board, and does not continue and lengthen or widen the dimensions of the circuit board in the longitudinal or transverse direction, the original dimensioning of the circuit board in terms of length and width is largely retained. This only occurs in depth, as viewed in the Z direction, for example in accordance with the exemplary embodiment in FIG. 1 additional correction element as a further layer to the printed circuit board inside the housing of the mobile radio device.

The coupling of at least one virtual current path-extending correction element to the printed circuit board of a radio communication device is particularly useful when radio communication devices are used as intended, e.g. Cellular devices or cordless phones advantageous. Because the controlled current path extension with the aid of the correction element, the magnetic field strength in the vicinity of the antenna of the respective radio communication device and thus in the vicinity of the respective user can be generated more homogeneously when the radio communication device is used as intended, and the SAR values can be reduced. At the same time, this enables improved power radiation.

In the field of mobile radio technology, there is a particular trend towards increasingly small-volume mobile communication terminals. In addition to the width and thickness, this in particular reduces the length of the devices. Since the frequency range in which the radio is supposed to work is fixed and thus remains unchangeable, the ratio of device length to wavelength is reduced. This influence leads to a reduced power radiation of the respective device, since the effective length of the antenna is reduced. This could be compensated for by increasing the input power for the antenna, which in turn would have the effect that higher currents could flow on the circuit board. This would in turn lead to an increase in the SAR value, which is undesirable. In contrast, the virtual current path extension according to the invention by means of at least one correction element on the printed circuit board reduces the so-called * hot spots "and / or shifts them into less critical device zones. This can improve the power radiation and the SAR values can be reduced the correction element according to the invention even advantageously as Design element can be used. For example, it can be integrated into the display device or keyboard of the respective radio communication device.

Other approaches that are possible in addition to or independently of the correction element according to the invention are as follows:

a) Increasing the distance between the areas with a large current amplitude in the mobile radio device and in the head of the user:

For devices with an external antenna, the current maxima are located directly on the antenna. Consequently, this approach leads to external antennas, which are located on the back of the device and are often bent away from the head of the respective user. In the case of devices with an integrated antenna, this is expediently accommodated on the side of the printed circuit board facing away from the head inside the housing of the respective mobile radio device. In addition, it can be expedient to make these devices as thick as possible in order to make the distance between the printed circuit board and the head of the user as large as possible. In particular, the distance between the printed circuit board and the user's head is maximized where the mobile radio device rests directly on the cheek of the respective user. Furthermore, it is advantageous to attach the circuit board relatively close to the back shell and to give it the largest possible gap distance to the top shell. In practice, excessive device thickening is undesirable for the maneuverability of the devices. In addition, a reduction of the SAR values with this approach is only possible to a limited extent due to the given dimensions of the radio devices.

b) Shielding the electromagnetic radiation power in the direction of the user's head: With this approach alone, the directional beam characteristic of the radio communication devices is changed in the horizontal plane. The directivity ensures an increased radiation power towards the rear of the device and a reduced radiation power towards the head. This effect can be seen with integrated antennas that have a full-area ground surface on the circuit board that acts as a reflector. However, an excessive increase in the directional effect is not desired in the case of mobile radio antennas and is also physically limited, since otherwise the transmission and reception operations would be disturbed too much.

c) Absorption of the electromagnetic radiation power with lossy material in the areas responsible for high SAR values:

This approach on its own has the disadvantage, however, that complex radiation power can simply be destroyed again. This leads to a reduced performance (performance) of the mobile radio devices, in particular to shorter standby times and busy times, which is undesirable. Such approaches are known for example from EP 0 603 081 AI.

d) Reduction or distribution of the high-frequency currents. With this approach, different variants are more advantageous

Possible way:

i.) Without changing the radio, the radiated power is simply reduced and thus the radiated power in the head at the same time. However, this approach on its own is exhausted by the prescribed minimum required output power. A further reduction in the SAR value does not appear to be possible.

ii.) The circuit board is widened. An increase in the width of the printed circuit board has the same effect Current in the longitudinal direction of the circuit board a reduction in the current density and thus a reduced SAR value. This approach on its own, however, cannot be used for a further reduction in the SAR value due to the dimensions of the housing for mobile radio devices.

Claims

claims

1. Radio communication device (MP) with at least one printed circuit board (LP) accommodated in a housing (GH), given longitudinal (L) and transverse dimensions (B), and with at least one antenna (ATI) for radiating and / or receiving electromagnetic Radio radiation field, which is coupled to this printed circuit board (LP), characterized in that at least one additional, electrically conductive correction element (ZVl) is coupled and designed on the printed circuit board (LP) in such a way that for one on the printed circuit board (LP) possibly by electromagnetic radio radiation fields electrical current (I (X)) caused by the antenna (ATI) is a targeted, fictitious current path extension (WV) while largely maintaining the specified longitudinal and transverse dimensions of the circuit board (LP).

2. Radio communication device according to claim 1, characterized in that the additional correction element (ZVl) is coupled and designed on the printed circuit board (LP) in such a way that such a fictitious current path extension (WV) causes the electrical current (I (X)) which leads to a desired SAR reduction (specific absorption rate) in the area surrounding the printed circuit board (LP).

3. Radio communication device according to one of the preceding claims, characterized in that the respective additional correction element (ZVl) is positioned such that its imaginary orthogonal projection with respect to the component placement area of the printed circuit board (LP) essentially within one by the side edges (SRL, SRR , SRO, SRU) of the printed circuit board (LP) spanned boundary surface (BF).

4. Radio communication device according to claim 3, characterized in that the respective additional correction element (ZVl) in a spatial area within, and / or above, and / or below, and / or laterally on the side edges (SRL, SRR, SRO, SRU ) the circuit board (LP) spanned boundary surface (BF) is arranged.

5. Radio communication device according to one of the preceding claims, characterized in that one or more electrical wires, at least one single-layer or multilayer electrically conductive film, coating and / or another electrically conductive surface element is provided as a current-conductive correction element (ZVl).

6. Radio communication device according to one of the preceding claims, characterized in that the respective correction element (ZVl) is coupled and designed such that for an electrical current (I (X)) which is a main flow direction along the longitudinal extent (L) of the printed circuit board (LP ), a fictitious current path extension (WV) is provided essentially in this direction.

7. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZVl) is attached in the region of that end of the circuit board (LP) which is opposite the end of the circuit board (LP) with the coupling area of the antenna (ATI).

Radio communication device according to one of the preceding claims, characterized in that the printed circuit board (LP) is essentially rectangular.

9. Radio communication device according to one of the preceding claims, characterized in that the printed circuit board (LP) has a greater longitudinal extent (L) than width (B).

10. Radio communication device according to one of claims 8 or 9, characterized in that the correction element (ZV2) and the antenna (AT2) on the circuit board (LP) are mounted relative to one another such that they essentially two diagonally opposite, electrically effective corner areas of the Printed circuit board (LP) are assigned.

11. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZVl) and the antenna (ATI) are attached to the printed circuit board (LP) in such a way that when viewed together they form an electrical roof capacitance.

12. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZVl) is formed by a U-profile-like extension element which rests roof-like on the front end of the printed circuit board (LP) facing away from the antenna (ATI).

13. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZVl) is formed by an electrically conductive extension element which, starting from the printed circuit board (LP), into one or more layer levels within and / or above and / or below the boundary surface (BF) in one or more layer levels is folded over and / or bent several times.

14. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZV2) is meandering.

15. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZV3) is formed by the separate antenna mass of a PIFA (planar inverted-F) antenna.

16. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZV4) is formed by at least one electrically conductive coating on the battery unit (AK) of the radio communication device.

17. Radio communication device according to one of the preceding claims, characterized in that at least one correction element (ZV6) is designed as an integral part of the circuit board mass of the circuit board (LP), in particular in a meandering form.

Radio communication device according to claim 17, characterized in that a partial area (ZV6) of the ground plane of the printed circuit board (LP) is designed so separately from it in the same position plane that it acts as an extension of the current path.

19. Radio communication device according to one of the preceding claims, characterized in that the correction element (ZV2) has such a longitudinal extension that for an electrical current (I (X)) flowing along the longitudinal direction (X) of the printed circuit board (LP) a fictitious path extension (WV) of 1.1 times to 1.5 times the original longitudinal extension (L) of the printed circuit board.

20. Radio communication device according to one of the preceding claims, characterized in that the antenna (ATI) is designed as a λ / 4 antenna or PIFA (Planar Inverted F) antenna, which forms a radiation dipole together with the printed circuit board (LP).

21. Radio communication device according to one of the preceding claims, characterized in that the antenna (AT3) is designed as an essentially planar internal antenna.

22. Radio communication device according to one of claims 1 to 20, characterized in that the antenna (AT2) is designed as a rod antenna projecting outwards from the housing (GH).

23. Radio communication device according to one of the preceding claims, characterized in that that the respective correction element (KVl) is galvanically, capacitively, inductively and / or radially coupled to the printed circuit board (LP).

24. Radio communication device according to one of the preceding claims, characterized in that at least one of the correction elements is designed as a metallization of the housing shells (GH) and / or other parts of the radio communication device, and that these are connected to the ground system of the radio communication device.

25. Printed circuit board (LP) with at least one correction element (KVl - KV6) according to one of the preceding claims.

26. Mobile radio device or cordless telephone with at least one printed circuit board according to claim 25.