DE19919107A1 - Mobile radio transceiver with tunable antenna - Google Patents

Abstract

The aim of the invention is to realize a transmission-reception that can be carried out in various frequency ranges using radio transmitting-radio receiving devices (SE) which ensure a consistently stable antenna gain. To this end, the radio transmitting-radio receiving devices (SE) are equipped with an antenna (ANT) whose length (lANT) can be adjusted, whereby the antenna length (lANT) is varied by adjusting means (VM) that are controlled by a control device ( mu P). The control device ( mu P) controls the adjusting means (VM) according to physical input quantities (EG) which represent the antenna length (lANT) until the antenna length (lANT) corresponds to one-fourth the size of the wavelength ( lambda ).

Description

In radio communication systems, messages (at for example, language, image information or other data) Transmitted with the help of electromagnetic waves. The abstrah len of the electromagnetic waves takes place through antennas, where the carrier frequencies, in that for the particular system provided frequency band.

In addition to the requirement that mobile radio transmit / radio Em to limit the dimensions of the antenna are, there is also an increasing demand for Sending / receiving capability in different frequency ranges chen. For this reason antennas are needed, which in meh other frequency ranges can be used.

With conventional antennas, for example rod-shaped those that are used in particular in handsets, can the required coverage of the largest possible Fre range or multiple frequency bands be made since the impedance of the antenna depends on the Frequency varies widely, which varies widely Antenna gain has the consequence that a use of the antenna is not possible in certain frequency ranges.

Therefore, antenna systems have hitherto been used to solve this problem in use, which consist of several antennas, each of which because it covers a certain frequency range.

A disadvantage of such antenna systems on the one hand the increased space requirement and on the other hand one suboptimal adaptation of the antennas to the individual frequencies zen from the respective frequency band.  

The object underlying the invention is a mo bile radio transceiver to design such that, when covering a large frequency range, ensures a constant, stable antenna gain.

This object is ge by features of claim 1 solves.

The inventive mobile radio transceiver device according to claim 1

• - A length-adjustable antenna that is used for transmission and receiving radio signals of different frequencies zen or - the corresponding - wavelengths within a large frequency range is provided,
• - Means (device) for adjusting the antenna length,
• Means for detecting at least one physical a function of the input length representing the antenna length eat
• - A control device connected to the means, the reads in at least one input variable and depends on it of this input variable as long as at least one output signal (control signal) generated with which the means for ver set the antenna length is controlled until by the Adjustment means the antenna length to a quarter of the world length is set,

on.

The essential advantage of the mobile radio Transmitting / receiving device is a stable antenna gain, by adjusting the antenna length to a quarter of the Wavelength of the current frequency is guaranteed, independent depending on the size of the frequency range in which the mobile Radio transmission / reception device is used.

A major advantage of further training according to claim 2 is the acquisition and the - for digital signal processing processing required - preparation of forward and / or backward  fender transmission power of the radio signal, which is a simple Er reaching the ideal antenna length (antennas length = wavelength / 4) enable.

A major advantage of further training according to claim 3 is the acquisition and - for digital signal processing required - preparation of the antenna impedance, the one easy detection of reaching the ideal antenna length (Antenna length = wavelength / 4) enable.

A major advantage of the training according to claim 4 is the simple realization that is necessary for the implementation of the inventions mobile radio transceiver according to the invention necessary adjustable antenna.

A major advantage of the training according to claim 5 is the possibility for the wire to retract and extend the on tenne, to be able to use materials that are not particularly stiffness but only high tear resistance and Must have flexibility.

Advantages of the developments according to claims 6 and 7 are simple implementation of the implementation of the fiction According to the mobile radio transceiver required adjustable antenna and the greater attractiveness vity for the buyer or user by concealing the Do not conduct an antenna length change using an electrically the hollow body.

A major advantage of further training according to claim 8 is the realization of a simple device for adjusting len the antenna length that only one control signal needs.

A major advantage of further training according to claim 9 is the implementation of simple means of adjusting the antennas length that only require a control signal, the adj in defined steps (step angle).  

The main advantages of further training according to claim 10 are Flexibility and possibility to update the implementation of the Control made possible by the use of (control) software light as well as the possibility of existing processes sensors for the control of the mobile radio Transmitting / radio receiving device through the use of additional licher or adapt the existing software.

The main advantages of further training according to claim 11 are the simple and inexpensive realization of the control unit like the possibility of this rear derailleur as an integrated scarf implementation in an expansion module.

The main advantage of further training according to claim 12 are the favorable material properties - high flexibility with high rigidity - from nylon.

The main advantage of further training according to claim 13, is the possible use of the mobile radio transmission / radio Receiving device in a frequency range in which the Ver ratio of the highest to the lowest frequency at least 1.5 Is octaves.

Embodiments of the invention are explained with reference to FIGS. 1 to 4. Show:

Fig. 1 Mobile radio transmitting / radio receiving device with telescopic antenna tromotor switched with a controlled Elek and can be extended,

Fig. 2 mobile radio transceiver with wire antenna, which - guided by a hollow body - with an electric motor and extended who can

Fig. 3 Mobile radio transmitting / receiving device with the forward and / or returning transmit power dependi gen setting of the antenna length,

Fig. 4 Mobile radio transceiver with the antenna impedance-dependent setting of the antenna NEN length.

Fig. 1 shows a mobile radio transceiver device SE with a trained as a telescopic antenna ANT1 Sen de / receive antenna, a minimum radio-effective antenna length lan the telescopic antenna ANT1 is determined by the length of an outermost telescope segment, and ei ne maximum effective antenna length l _{max is} determined by the length of the fully extended telescopic antenna ANT1. Inside the telescopic antenna ANT1, an electrically non-conductive wire D1, for example a nylon wire, is attached to its tip, which is designed so that it has sufficient rigidity to extend the telescopic antenna ANT1, has sufficient flexibility to to be able to wind an electrically non-conductive bobbin by SP1 and has sufficient strength to retract the telescopic antenna ANT1.

As an alternative to nylon, other materials which have the properties described can also be used, wherein if the material used is not sufficiently rigid, as a spring which is attached to an innermost telescope segment and the antenna base within the telescopic antenna ANT1 and in the relaxed state - by Pressure on the innermost telescope segment - the maximum length l _{max of} the telescopic antenna ANT1 ensures, is used and the electrically non-conductive wire D1 used only has to have sufficient (tear) strength and flexibility.

The coil former SP1 is powered by an electric motor VM is designed as a stepper motor, forwards or backwards turned so that the electrically non-conductive Spu steering body SP1 and wire D1 attached to the antenna tip  the rotation of the bobbin SP1 in a straight line movement implementation and thereby retracting or extending the telephoto scope antenna ANT1 enables. The (step) angle as well as the Direction of rotation are by the amount, the sign and / or the duration of a voltage applied to the electric motor VM (Control signal) UST determined.

This voltage U _ST is a signal (control signal) present at the output of a control unit (microprocessor) μP, the amount, sign and / or signal duration of which is dependent on input variable EG present at the control unit μP.

The control unit µP controls the electric motor VM by the signal U _ST until the radio-active antenna length l _ANT corresponds to a quarter of the wavelength λ of the current sensor frequency. The control unit µP determines indirectly whether the condition l _Ant = λ / 4 is fulfilled by evaluating the input variable EG, the input variable EG indicating the fulfilled condition l _Ant = λ / 4 when an ideal value is reached. First, the coil body SP1 is controlled so that it is always rotated in a predetermined direction (default) at the beginning of the regulation. If the evaluation shows that the input variable EG is moving away from the ideal value, the direction of rotation is changed and the electric motor VM is activated until the input variable EG has reached the ideal value.

Alternatively, it is possible to additionally start the control from a defined starting point, for example always from the retracted state of the telescopic antenna, and therefore first to ensure this starting point when starting the control. This procedure is particularly necessary when using the mobile radio transceiver SE in a very wide frequency range, in which the ratio of the highest to the lowest frequency is at least 1.5 octaves, because otherwise - depending on the An antenna _ANT current length l - the case may occur that the control of antenna length l _{ANT ANT} at l = 3 is λ / terminated. 4 Since in this case the input variable EG also reaches the ideal value, but with this value of the antenna length l _ANT the inventive task is not solved, this value of the antenna length l _{ANT is} not desired. The end of the regulation of the antenna length l _ANT when this value is reached can be prevented if, for example, a suitable control software starts the regulation of the antenna length l _ANT at the minimum radio-technically effective antenna length l _{ANT, min} , and this ensures that the input variable EG when the ideal value is reached, the condition l _ANT = λ / 4 is always met.

The possibly processed input variable EG receives the control unit μP from means EFM for the detection of physical input variables EG dependent on an antenna length l _ANT , which are transformed by these means into a form necessary for the control unit μP (see FIG. 3 and 4).

Alternatively, the EFM means also cover several physical ones Input variables EG and, if necessary, prepare them before they start the control unit µP are forwarded, the tax unit µP corresponding to several input variables on the achievement check an ideal value.

The antenna connection of the telescopic antenna ANT1 is located on the outermost telescope segment of the antenna.

In Fig. 2, a wire antenna ANT2 is shown, the radio-technically effective length l _ANT from the diameter of an electrically conductive coil body SP2, on which an electrically conductive wire D2 is electrically conductively connected, and the length of the extended wire D2 gives.

The electrically conductive wire D2 is when retracting and extending due to an electrically non-conductive rotationally symmetrical Hollow body HK, which is closed at one end.  

The minimum radio antenna length l _{ANT, min of} the wire antenna ANT2 results from the diameter of the coil body SP2 and the distance between the coil body SP2 and the open side of the hollow body HK, which the electrically conductive wire D2 must cover. The maximum radio-effective antenna length l _{ANT, max} results from the diameter of the coil body SP2 and the distance between the coil body SP2 and the closed side of the hollow body HK, which the electrically conductive wire D2 must cover.

The antenna length lMJT is regulated, for example, by the components known from FIG. 1:
EFM means for detecting and processing physical input variables EG dependent on the antenna length l _ANT , control unit μP for evaluating the input variables EG and generating the corresponding control signal U _ST for actuating the electric motor VM, which rotates the coil former SP2 accordingly in one direction, the through the hollow body HK led wire D2 converts the rotary movement of the coil body SP2 into a straight movement.

The hollow body HK additionally fulfills the function of laminating the wire antenna ANT2, ie the movement of the wire D2, which results from the regulation of the antenna length l _ANT , is not visible to the user, which makes the attractiveness of the mobile radio transmitter / Radio receiving device SE increased. In addition, the HK hollow body protects the D2 wire from deformation.

The antenna connection of the wire antenna D2 is through a electrically conductive coil body SP2 touching grinding con clock SK realized, alternatively the sliding contact SK also on the electrically conductive, on the spool SP2 can touch wound wire D2.  

In Fig. 3, a radio transmitting / radio receiving device SE is schematically illustrated, the variable with an arbitrary, in ih rer length l _ANT antenna ANT, the adjusting VM to adjust the antenna length l _ANT, the control unit .mu.P and means EFM for detecting a transmission signal SIG, which is generated by a radio part FT.

For this purpose, the means EFM have a directional coupler RK, which couples a leading transmission power P _V and a returning transmission power P _R from the transmission signal SIG. The leading transmit power P _V is then first rectified by a first rectifier G1 and the rectified preliminary transmit power P _V 'is then converted by a first analog / digital converter AD1 into a first digital signal P _V ". The returning transmit power P _R is converted from rectified by a second rectifier G2 and the rectified return transmitting power P _R 'is subsequently converted by a second analog / digital converter AD2 into a second digital signal P _R ".

The digital signals P _V ", P _R " are present as an input signal to the control unit µP, the control unit µP being designed, for example, as a (micro) processor with associated software. The processor uP generated at adjacent Si gnalen P _V "P _R" checked whether the signals P _V "P _R" are each an ideal value - P _R = 0 and P _R "= P _{R, min"} and P _V ' = P _{V, max} "- have reached.

If this is the case, the current antenna length l _ANT fulfills the condition l _ANT = λ / 4. In this case, no control signal UST is generated since it is not necessary to change the antenna length l _ANT .

If this is not the case, the processor µP first generates a first control signal U _ST , so that the adjusting device (VM) extends the antenna. The input signals P _V ", P _R " which are changed by this process and which are present at the processor are checked by the processor μP with regard to the ideal values to be achieved. If the values of the signals P _V ", P _R " have deteriorated with a view to reaching the ideal values, the direction of rotation of the means (VM) for adjusting the antenna length l _{ANT is} changed. This is achieved, for example, by reversing the sign of the signal U _ST .

The signal U _ST is generated after the determination of the correct direction until the input signals P _V ", P _R " have reached their ideal values.

Alternatively, only one of the quantities - leading transmit power P and returning transmit power P _R - can be used as a controlled variable for this control loop, ie detected by the EFM means and by the processor µP when the ideal values are reached - minimal or no decreasing transmit power or maximum leading transmission power - to be checked.

As an alternative to using an additional µP processor it would be conceivable that existing processors by ei ne suitable control software to be upgraded to this re to be able to perform.

If an additional processor µP were used, one would also be Integration of the EFM means in the processor µP conceivable.

The radio transceiver device SE shown in FIG. 4 again has the means EFM for detecting the current antenna impedance Z _{ANT of} the antenna ANT.

For this purpose, the means EFM are designed as a Wheatstone resistance measuring bridge with a reference resistor R0 = 50 Ω, two resistors R1, R2 having the same resistance value, the antenna impedance Z _ANT as a variable variable and a source (G _NOISE ) for generating noise, for example realized by a diode connected to a DC voltage source. A current bridge voltage U _BR present at terminals KL is first rectified by a rectifier and the rectified voltage U _BR 'is converted into a digital signal U _BR "by means of an analog / digital converter AD3.

The signal U _BR "is passed on to a control unit µP which, when a signal is present, starts regulating the antenna length l _ANT , which ends when the signal U _BR " is minimal or U _BR "= 0 In this case, the antenna length l _ANT fulfills the condition l _ANT = λ / 4.

The change in the antenna length l _ANT is carried out by the adjusting device VM, the determination of the direction of the antenna length l _ANT - ie whether the antenna should be extended or retracted - analogous to the previous exemplary embodiment.

Alternatively, it is conceivable to use the control unit µP as a switch design and as an integrated circuit in one to implement a special expansion module.

A first embodiment of the invention results from a combination of FIGS. 1 and 3, a second exemplary embodiment results from FIGS . 1 and 4, a third embodiment from FIGS . 2 and 3 and a fourth from FIGS. 2 and 4.

The four exemplary embodiments mentioned represent only one Part of the embodiments possible by the invention. So an expert working in this area is able to due to advantageous modifications a variety of others To create embodiments without losing the character (Essence) of the invention is changed. These embodiments should also be covered by the invention.

Claims (13)

1. Mobile radio transceiver (SE) with the following features:

• a) an antenna (ANT) for transmitting radio signals (SIG) of different wavelengths (λ), the length of which can be changed,
• b) means (VM) for adjusting the antenna length (l _ANT ),
• c) means (EFM) for detecting at least one physical input variable (EG) representing a function of the antenna length (1 _ANT ),
• d) a control device (µP) connected to the detection means (EFM), which controls the adjustment means (VM) by means of at least one control signal (U _ST ) depending on the input variable (EG) or the input variables (EG) until the antenna length (l _ANT ) is set to a quarter of the wavelength (λ) by the adjustment means (VM).

2. Mobile radio transceiver (SE) according to claim 1, characterized in that

• a) the detection means (EFM) have a directional coupler (RK) for measuring a forward transmission power (P _V ) and / or a return transmission power (P _R ) of a transmission signal (SIG),
• b) the detection means (EFM) for rectifying the values of the forward transmission power (R _V ) and / or returning transmission power (P _R ) measured by the directional coupler (RK) is equipped with at least one rectifier (G1, G2) which is a rectified leading one Generate transmission power (P _V ') and / or a rectified return transmission power (P _R '),
• c) the detection means (EFM) for digitally converting the rectified values of the leading transmission power (P _V ') and / or returning transmission power (P _R ') have at least one A / D converter (AD1, AD2) which has a digital ge converted leading transmission power (P _V ") and / or a digitally converted returning transmission power (P _R "),
• d) the control device (µP) reads in the digitally converted values of the leading transmit power (P _V ") and / or return the transmit power (P _R ") as input signals and generates the control signal (U _ST ) dependent thereon until the value of the digital converted forward transmission power (P _V ") is maximum and / or the value of the digitally converted returning transmission power (P _R ") is minimal.

3. Mobile radio transceiver (SE) according to claim 1, characterized in that

• a) the detection means (EFM) have a Wheatstone measuring bridge (WM) which generates a bridge voltage (U _BR ) proportional to an impedance (Z _ANT ) of the antenna (ANT1, ANT2),
• b) the detection means (EFM) have a noise generator (G _NOISE ), which serves as an input signal source for the Wheatstone measuring bridge (WM),
• c) the detection means (EFM) are equipped with a rectifier (G3) for rectifying the bridge voltage (U _BR ) of the Wheatstone measuring bridge (WM), which generates a rectified bridge voltage (U _BR '),
• d) the detection means (EFM) for digital conversion of the rectified value of the bridge voltage (U _BR ') of the Wheat stone measuring bridge (WM) have an A / D converter (AD3), which he a digitally converted bridge voltage (U _BR ") testifies
• e) the control unit (µP), which reads in the digitally converted value of the bridge voltage (U _BR ") of the Wheatstone measuring bridge (WM) as an input signal and generates a dependent control signal (U _ST ) until the Wheatstone measuring bridge ( WM) is adjusted.

4. Mobile radio transmitting / receiving device (SE) according to one of the preceding claims, characterized in that

• a) the antenna (ANT) is a telescopic antenna (ANT1), to which an electrically non-conductive wire (D1) is attached to the inside of the antenna tip,
• b) the adjusting means (VM) have an electrically non-conductive coil body SP1 on which the electrically non-conductive wire (D1) is wound,
• c) the electrically non-conductive wire (D1) is such that it converts the rotary movement of the coil former (SP1) into a linear movement in order to retract and / or extend telescopic segments of the telescopic antenna (ANT1).

5. Mobile radio transceiver (SE) according to An saying 4, characterized in that the telescopic antenna (ANT1) to support the wire (D1) to extend the telescopic antenna (ANT1) with a spring All telescope segments of the telescopic antenna are permitted (ANT1) pushes outwards so that the telescopic antenna (ANT1) is fully extended. 6. Mobile radio transmitting / receiving device (SE) according to one of claims 1 to 3, characterized in that

• a) the adjusting means (VM) have an electrically conductive coil body (SP2), on which an electrically conductive wire (D2) connected to the coil body (SP2) is wound,
• b) the electrically conductive wire (D2) is designed such that it converts a rotary movement of the coil former (SP2), guided by an electrically non-conductive hollow body (H), into a linear movement,
• c) the antenna (ANT) is designed as a wire antenna (ANT2), which is composed of the extended wire (D2) and the electrically conductively connected coil former (SP2), with a connection of the wire antenna (ANT2) via an electrically conductive sliding contact ( SK) is realized, which touches the coil body (SP2) at the base.

7. Mobile radio transceiver (SE) according to egg nem of claims 1 to 3, characterized in that

• a) the adjusting means (VM) have an electrically non-conductive coil body (SP2), on which an electrically conductive wire (D2) connected to the coil body (SP2) is wound,
• b) the electrically conductive wire (D2) is such that it converts a rotational movement of the coil former (SP2), guided by an electrically non-conductive hollow body (HK), into a straight-line movement,
• c) the antenna (ANT) is designed as a wire antenna (ANT2), which is composed of the extended wire (D2) and the electrically connected coil former (SP2), with a connection of the wire antenna (ANT2) via an electrically conductive sliding contact (SK) is realized, which touches the wire (D2) wound on the coil former (SP2) at the base point.

8. Mobile radio transceiver (SE) according to one of the previous claims, characterized in that the adjustment device (VM) is an electric motor. 9. Mobile radio transceiver (SE) after the Claim 8 characterized in that that the electric motor is a stepper motor. 10. Mobile radio transceiver (SE) according to one of the preceding claims, characterized in that the control unit (µP) has a processor with a for the generation of the control signal (U _ST ) or the control signals (U _ST ) is from designed software. 11. Mobile radio transmitting / receiving device (SE) according to ei nem of claims 1 to 9, characterized in that the control unit (µP) is designed as a switching mechanism. 12. Mobile radio transceiver (SE) according to An saying 4, characterized in that the electrically non-conductive wire (D1) as a nylon wire is formed. 13. Mobile radio transceiver (SE) according to one of the preceding claims, characterized in that the control unit (µP) is designed such that at the beginning of the setting of the antenna length (l _ANT ), the antennas length (l _ANT ) to a minimum value (l _{ANT, min} ).