JPH0983399A - Receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To match the center frequency of output signal of a mixer with the center frequency of a filter, regardless of the change of ambient temperature and to suppress the degradation of the bit error rate at the time of reception. SOLUTION: This receiver is provided with a signal generation means 3 controlled from the outside, a temperature detection means 8, a storage means 9 and a control means 7. The set value of a signal generation means 3 that the center frequency of the output signal of a mixer 2 and the center frequency of a filter 4 is matched with each other is stored in a storage means 9 according to an ambient temperature condition. At the time of a reception, the set of the signal generation means 3 according to the temperature condition detected by a temperature detection means 8 is read from the storage means 9 and the set of the signal generation means 3 is controlled by this set value.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to receivers.

[0002]

2. Description of the Related Art FIG. 10 is a functional block diagram showing an example of a receiver using a conventional technique. The operation of the conventional receiver will be described with reference to FIG. The received signal is the first filter 10
After being band-limited by, it is amplified by the first amplifying means 11. The output signal of the first amplifying means 11 is band-limited by the second filter 12 and then input to the first mixer 13. The first mixer 13 inputs the output signal of the local oscillator 14 and the output signal of the second filter 12 and converts the output signal to the first intermediate frequency fIF1. The output signal of the first mixer 13 is band-limited by the third filter 15 and then input to the second mixer 16. Second mixer 16
Has a function of inputting the output signal of the third filter 15 and the output signal of the signal generating means 3 and converting it to the second intermediate frequency fIF2. The output signal of the second mixer 16 is band-limited by the fourth filter 17 and then input to the second amplifier 18. The output signal of the second amplifier 5 is demodulated by the demodulation means 6. In the conventional technique, the signal generating means 3 in FIG. 10 is configured to transmit at a fixed frequency.

[0003]

Generally, the band limitation by the first filter 10 and the second filter 12 is performed so that the entire reception band having a plurality of reception channels is transmitted. Further, the band limitation by the third filter 15 and the fourth filter 17 is performed so that one reception channel is transmitted. Of these, changes in the characteristics of the third filter 15 and the fourth filter 17, which have narrower pass bands, greatly affect the reception characteristics. Therefore, in the conventional technique in which the signal generating means 3 transmits at a fixed frequency, there is a problem that when the center frequency of the fourth filter 17 changes, the reception characteristic deteriorates depending on the degree of the change.

Here, as an example, the "second-generation cordless telephone system" established by the Radio System Development Center of the Foundation.
Consider a receiver that complies with. The modulation method uses the π / 4 shift QPSK method, and the roll-off rate of the fourth filter 17 is designed to be 0.5 in order to suppress intersymbol interference. The band characteristic and the group delay characteristic of the fourth filter 17 are deeply related to the bit error rate, which is one of the reception characteristics. Fourth filter 17 used in receiver conforming to "second generation cordless telephone system"
Is generally a center frequency of 10.
It is a 7 MHz filter. 11 and 12 are the fourth
5 is a graph showing an example of actually measured values of insertion loss and group delay characteristic of the filter 17 of FIG. It can be confirmed from FIGS. 11 and 12 that the center frequency of the fourth filter 17 becomes lower as the ambient temperature Ta becomes lower. In addition, an example of the actual measurement value of the bit error rate of the receiver at the same ambient temperature is shown in FIG.
Shown in From the figure, it can be confirmed that the bit error rate deteriorates because the signal generating means 3 transmits at a fixed frequency even though the center frequency of the fourth filter 17 changes.

An object of the present invention is to provide a receiver in which the bit error rate does not deteriorate even when the ambient temperature changes.

[0006]

In order to achieve the above object, the present invention provides a temperature detecting means having a function of detecting an ambient temperature, a storage means for storing a set value of the signal generating means, and the signal generating means. Is newly provided, and the control means stores the oscillation frequency setting value of the signal generating means, which matches the center frequency of the output signal of the mixer and the center frequency of the filter, in the storage means according to the ambient temperature. The oscillation frequency setting value of the signal generating means is stored and read from the storage means according to the ambient temperature detected by the temperature detecting means at the time of reception, and the oscillation frequency of the signal generating means is set using this setting value. The center frequency of the output signal of the mixer is controlled to match the center frequency of the filter regardless of the change in ambient temperature.

[0007]

The conventional receiver is additionally provided with temperature detecting means having a function of detecting the ambient temperature, storage means for storing the set value of the signal generating means, and control means for setting the signal generating means. The control means stores the oscillation frequency setting value of the signal generation means that matches the center frequency of the output signal of the mixer and the center frequency of the filter in the storage means according to the ambient temperature, and sets it to the ambient temperature detected by the temperature detection means during reception. Accordingly, the oscillation frequency setting value of the signal generating means is read from the storing means, and the setting value is used to control the oscillation frequency of the signal generating means to control the center of the mixer output signal regardless of the change in ambient temperature. The frequency can be matched with the center frequency of the filter, and the deterioration of the bit error rate during reception can be suppressed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention. The receiver of this embodiment has a front end 1 having a function of amplifying, band limiting or frequency converting a received signal, a signal generating means 3 capable of setting an oscillation frequency from the outside, an output signal of the front end 1 and a signal generating means. Mixer 2 for inputting the output signal of 3 and performing frequency conversion
And a filter 4 for band limiting the output signal of the mixer 2,
An amplifier 5 for amplifying the output signal of the filter 4, and an amplifier 5
Demodulation means 6 for inputting and demodulating the output signal of 1, the temperature detection means 8 for detecting the ambient temperature, the storage means 9 for storing the set value of the signal generation means 3, and the signal generation means 3.
And a control means 7 having a function of setting Next, the operation of the control means 7 will be described. The oscillation frequency set value of the signal generation means 3 at which the center frequency of the output signal of the mixer 2 and the center frequency of the filter 4 match is stored in the storage means 9 according to the ambient temperature. FIG. 2 shows an example thereof. Signal generating means 3
The oscillation frequency set value Vt is stored in the storage means 9 in association with an arbitrary temperature condition. At this time, the number of temperature conditions is arbitrary. FIG. 3 shows a method of setting the oscillation frequency setting value of the signal generating means 3. The center frequency ffi of the filter 4 is shown in FIG.
1 is a graph showing the temperature characteristic of FIG. 1, (b) is a graph showing the relationship between the center frequency fIF2 of the output signal of the mixer 2 and the oscillation frequency fL2 of the signal generating means 3, and (d) is the signal generating means 3
5 is a graph showing the relationship between the oscillation frequency fL2 and the set value Vt. Now ffi1 = fIF2, that is, mixer 2
Considering the case where the center frequency of the output signal of the filter and the center frequency of the filter 4 match, the oscillation frequency setting values Vt1, Vt of the signal generating means 3 with respect to the ambient temperatures T1, T2, T3.
2, Vr3 is obtained. When these are made to correspond to the ambient temperature Ta, the characteristics shown in FIG. Therefore, if the temperature change of the center frequency of the filter 4 is known, the set value of the signal generating means 3 can be determined. In addition, the modulation accuracy or eye pattern of the received signal is observed in the adjustment process during the manufacturing of the receiver, and the oscillation frequency set value of the signal generation means 3 that gives the best result is stored in the storage means 9 according to an arbitrary temperature condition. It may be stored. Signal generating means 3
After storing the oscillation frequency setting value of the storage means 9, the oscillation frequency setting value of the signal generating means 3 is read from the storage means 9 according to the ambient temperature detected by the temperature detecting means 8 at the time of reception, and this setting value is used. Control to set the oscillation frequency of the signal generating means 3. According to the present embodiment, the center frequency of the output signal of the mixer 2 can be matched with the center frequency of the filter 4 by the above control regardless of the change of the ambient temperature, and the deterioration of the bit error rate at the time of reception can be suppressed. it can.

FIG. 4 is a block diagram showing a second embodiment of the present invention. In this embodiment, the front end 1 of the receiver shown in the first embodiment includes a first filter 10 for band-limiting a received signal, and a first amplification means 11 for amplifying an output signal of the first filter 10. , The second filter 12 for limiting the output signal w band of the first amplifying means 11, and the output signal of the second filter 12 and the output signal of the local oscillator 14 are input and frequency-converted to the first intermediate frequency fIF1. This is a case where the first mixer 13 and the third filter 15 that band-limits the output signal of the first mixer 13 are included. Other configurations are the same as those of the first embodiment. That is, the signal generation means 3 whose oscillation frequency can be set from the outside, the second mixer 16 for inputting the output signal of the front end 1 and the output signal of the signal generation means 3 for frequency conversion, and the second mixer 16
A fourth filter 17 for band limiting the output signal of
Second amplifier 18 for amplifying the output signal of the filter 17 of
A demodulation means 6 for inputting and demodulating the output signal of the second amplifier 18, a temperature detection means 8 for detecting the ambient temperature, and a storage means 9 for storing the set value of the signal generation means 3. The control means 7 has a function of setting the signal generation means 3. Next, the operation of the control means 7 will be described. Second
The oscillation frequency setting value of the signal generating means 3 in which the center frequency of the output signal of the mixer 16 and the center frequency of the fourth filter 17 are stored in the storage means 9 according to the ambient temperature.
FIG. 5 shows an example thereof. The oscillation frequency setting value Vt of the signal generating means 3 is stored in the storage means 9 in association with an arbitrary temperature condition. At this time, the number of temperature conditions is arbitrary. FIG. 6 shows a method of setting the oscillation frequency setting value of the signal generating means 3. 6A is a graph showing the temperature characteristic of the center frequency ffi1 of the fourth filter 17, and FIG. 6B is a relationship between the center frequency fIF2 of the output signal of the second mixer 16 and the oscillation frequency fL2 of the signal generating means 3. And (d) is a graph showing the relationship between the oscillation frequency fL2 of the signal generating means 3 and the set value Vt. Now ffi1 = fIF2, that is, the center frequency of the output signal of the second mixer 16 and the fourth filter 1
Considering the case where the center frequency of 7 matches, the oscillation frequency setting values Vt1, Vt2, Vt3 of the signal generating means 3 are obtained for the ambient temperatures T1, T2, T3. When these are made to correspond to the ambient temperature Ta, the characteristics shown in FIG. 6C are obtained. Therefore, if the temperature change of the center frequency of the filter 4 is known, the set value of the signal generating means 3 can be determined. In addition, the modulation accuracy or eye pattern of the received signal is observed in the adjustment process during the manufacturing of the receiver, and the oscillation frequency set value of the signal generation means 3 that gives the best result is stored in the storage means 9 according to an arbitrary temperature condition. It may be stored. After the oscillation frequency setting value of the signal generating means 3 is stored in the storage means 9, the oscillation frequency setting value of the signal generating means 3 is read from the storage means 9 according to the ambient temperature detected by the temperature detecting means 8 at the time of reception. The setting value is used to control the oscillation frequency of the signal generating means 3. According to the present embodiment, the center frequency of the output signal of the second mixer 16 can be matched with the center frequency of the filter 4 by the above control regardless of the change of the ambient temperature, and the bit error rate at the time of reception can be prevented from deteriorating. Can be suppressed.

FIG. 7 is a block diagram showing a third embodiment of the present invention. In this embodiment, the signal generating means 3 shown in the second embodiment has a second local oscillator 19, a reference oscillator 21, a P
This is the case where the LL synthesizer 20 is used. The other structure is similar to that of the second embodiment. That is, the signal generating means 3 whose oscillation frequency can be set from the outside, the second mixer 16 for inputting the output signal of the front end 1 and the output signal of the signal generating means 3 for frequency conversion, and the second mixer 1
A fourth filter 17 for band limiting the output signal of No. 6 and a second amplifier 1 for amplifying the output signal of the fourth filter 17.
8, demodulation means 6 for inputting and demodulating the output signal of the second amplifier 18, temperature detection means 8 for detecting the ambient temperature,
The storage unit 9 has a function of storing the set value of the signal generating unit 3, and the control unit 7 having a function of setting the signal generating unit 3. Next, the operation of the control means 7 will be described. The setting value of the PLL synthesizer 20 in which the center frequency of the output signal of the second mixer 16 and the center frequency of the fourth filter 17 are closest to each other is stored in the storage means 9 according to the ambient temperature. FIG. 8 shows an example thereof. The set value data of the PLL synthesizer 20 is stored in the storage means 9 in association with an arbitrary temperature condition. At this time, the number of temperature conditions is arbitrary. FIG. 9 shows a method of setting the set value of the PLL synthesizer 20.
FIG. 9A shows the center frequency ffi1 of the fourth filter 17.
Showing the temperature characteristics of the second mixer 16, a graph showing the relationship between the center frequency fIF2 of the output signal of the second mixer 16 and the oscillation frequency fL2 of the signal generating means 3, and (d) a set value data of the PLL synthesizer 20. 3 is a graph showing the relationship between the signal generation means and the signal generation means. Considering the case where ffi1 = fIF2, that is, the case where the center frequency of the output signal of the second mixer 16 and the center frequency of the fourth filter 17 coincide with each other, the signal generating means 3 with respect to the ambient temperatures T1, T2, T3.
The oscillation frequency setting values Vt1, Vt2, Vt3 are obtained.
When these are made to correspond to the ambient temperature Ta, the characteristics shown in FIG. 6C are obtained.

However, the difference from the second embodiment is that the PLL
Since the set value data of the synthesizer 20 takes a discrete value, it becomes a discrete set value as indicated by ◯ in FIG.

Therefore, if the temperature change of the center frequency of the fourth filter 17 is known, the set value of the PLL synthesizer 20 can be determined. In addition, the modulation accuracy or the eye pattern of the received signal is observed in the adjustment process at the time of manufacturing the receiver, and the set value of the PLL synthesizer 20 that optimizes these is stored in the storage means 9 according to an arbitrary temperature condition. You may After the oscillation frequency set value of the PLL synthesizer 20 is stored in the storage means 9, the set value of the PLL synthesizer 20 is read from the storage means 9 according to the ambient temperature detected by the temperature detection means 8 at the time of reception, and this set value is used. Control to set the PLL synthesizer 20. According to the present embodiment, the center frequency of the output signal of the second mixer 16 can be closest to the center frequency of the fourth filter 17 regardless of the change of the ambient temperature by the above control, and the bit error at the time of reception can be obtained. The deterioration of the rate can be suppressed.

The receiver described in the above-mentioned embodiments is also effective for a wireless telephone, a wireless communication device, or a wired communication device equipped with these.

[0015]

According to the present invention, the conventional receiver has a temperature detecting means having a function of detecting an ambient temperature, a storage means for storing a set value of the signal generating means, and a signal generating means. The control means is newly provided, and the control means stores the oscillation frequency setting value of the signal generation means, which matches the center frequency of the output signal of the mixer and the center frequency of the filter, in the storage means according to the ambient temperature and detects the temperature when receiving. The oscillation frequency set value of the signal generating means is read from the storage means in accordance with the ambient temperature detected by the means, and the set value is used to control the oscillation frequency of the signal generating means to control the change of the ambient temperature. Therefore, the center frequency of the output signal of the mixer can be matched with the center frequency of the filter, and the deterioration of the bit error rate during reception can be suppressed.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operation of the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of the operation of the first embodiment of the present invention.

FIG. 4 is a block diagram of a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of the operation of the second embodiment of the present invention.

FIG. 6 is an explanatory diagram of the operation of the second embodiment of the present invention.

FIG. 7 is a block diagram showing a third embodiment of the present invention.

FIG. 8 is an explanatory diagram of an operation of the third embodiment of the present invention.

FIG. 9 is an explanatory diagram of the operation of the third embodiment of the present invention.

FIG. 10 is a block diagram showing a conventional technique.

FIG. 11 is an explanatory diagram of a conventional technique.

FIG. 12 is an explanatory diagram of a conventional technique.

FIG. 13 is a reception characteristic diagram when a conventional technique is used.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Front end, 2 ... Mixer, 3 ... Signal generation means, 4 ... Filter, 5 ... Amplifier, 6 ... Demodulation means, 7 ... Control means, 8 ... Temperature detection means, 9 ... Storage means.

Claims (8)

[Claims] 1. A front end having a function of amplifying, band limiting or frequency converting a received signal, a signal generating means having a function of setting an oscillation frequency from the outside, an output signal of the front end and the signal generating means. A mixer having a function of inputting an output signal of and performing frequency conversion,
A filter having a function of band limiting the output signal of the mixer, an amplifier having a function of amplifying the output signal of the filter, a demodulation unit having a function of inputting and demodulating the output signal of the amplifier, and an ambient temperature In a receiver including temperature detecting means having a detecting function, storage means having a function of storing a set value of the signal generating means, and control means having a function of setting the signal generating means, the control means Stores the oscillation frequency setting value of the signal generating means in which the center frequency of the output signal of the mixer and the center frequency of the filter match in the storage means according to the ambient temperature, and detects the temperature detection means at the time of reception. The oscillation frequency setting value of the signal generating means is read from the storage means according to the ambient temperature, and the signal generating means outputs the setting value using the setting value. A receiver characterized in that the center frequency of the output signal of the mixer is matched with the center frequency of the filter by controlling to set a vibration frequency regardless of changes in ambient temperature. 2. A front end having a function of amplifying, band limiting or frequency converting a received signal, a signal generating means having a function of setting an oscillation frequency from the outside, an output signal of the front end and the signal generating means. A mixer having a function of inputting an output signal of the mixer and performing frequency conversion, a filter having a function of band limiting the output signal of the mixer, an amplifier having a function of amplifying the output signal of the filter, and an output of the amplifier. Demodulation means having a function of inputting and demodulating a signal, temperature detection means having a function of detecting ambient temperature, storage means having a function of storing a set value of the signal generation means, and setting of the signal generation means In the receiver including a control unit having a function of performing the setting, the control unit sets the signal generation unit at an arbitrary reference temperature. A value is stored in the storage means, the amount of change in the center frequency of the filter is stored in the storage means according to the ambient temperature, and the center frequency of the filter is received according to the ambient temperature detected by the temperature detection means at the time of reception. The amount of change of the signal generation means is read from the storage means, and the oscillation frequency of the signal generation means is controlled by using the set value of the signal generation means at the reference temperature and the read amount of change of the center frequency of the filter. Thus, the center frequency of the output signal of the mixer is made to match the center frequency of the filter regardless of changes in ambient temperature. 3. A first device having a function of band-limiting a received signal.
Filter, a first amplifying means having a function of amplifying an output signal of the first filter, a second filter having a function of band limiting the output signal of the first amplifying means, and a local oscillator. A first mixer having a function of inputting an output signal of the local oscillator and an output signal of a second filter to perform frequency conversion, and a third filter having a function of band limiting the output signal of the first mixer A signal generating means having a function of setting an oscillation frequency from the outside, and a second mixer having a function of inputting an output signal of the third filter and an output signal of the signal generating means to perform frequency conversion. A fourth filter having a function of band limiting the output signal of the second mixer, a second amplifier having a function of amplifying the output signal of the fourth filter, and an output of the second amplifier Signal having a function of inputting a signal and demodulating, temperature detecting means having a function of detecting ambient temperature, storage means having a function of storing a set value of the signal generating means, and setting of the signal generating means And a control unit having a function of performing an oscillation frequency of the signal generation unit in which the center frequency of the output signal of the second mixer and the center frequency of the fourth filter match. The set value is stored in the storage unit according to the ambient temperature, and the oscillation frequency set value of the signal generation unit is read from the storage unit according to the ambient temperature detected by the temperature detection unit during reception, and the set value is set. The center frequency of the output signal of the second mixer is controlled by controlling the oscillating frequency of the signal generating means by using the. Receiver, characterized in that so as to coincide with the center frequency of the motor. 4. A first device having a function of band-limiting a received signal.
Filter, a first amplifying means having a function of amplifying an output signal of the first filter, a second filter having a function of band limiting the output signal of the first amplifying means, and a local oscillator. A first mixer having a function of inputting an output signal of the local oscillator and an output signal of a second filter to perform frequency conversion, and a third filter having a function of band limiting the output signal of the first mixer A signal generating means having a function of setting an oscillation frequency from the outside, and a second mixer having a function of inputting an output signal of the third filter and an output signal of the signal generating means to perform frequency conversion. A fourth filter having a function of band limiting the output signal of the second mixer, a second amplifier having a function of amplifying the output signal of the fourth filter, and an output of the second amplifier Signal having a function of inputting a signal and demodulating, temperature detecting means having a function of detecting ambient temperature, storage means having a function of storing a set value of the signal generating means, and setting of the signal generating means In a receiver including a control unit having a function of performing the above, the control unit stores the set value of the signal generation unit at an arbitrary reference temperature in the storage unit, and changes the center frequency of the fourth filter. Is stored in the storage means according to the ambient temperature, and the amount of change in the center frequency of the fourth filter is read from the storage means in accordance with the ambient temperature detected by the temperature detection means at the time of reception, at the reference temperature. The ambient temperature is controlled by controlling to set the oscillation frequency of the signal generating means by using the set value of the signal generating means and the read change amount of the center frequency of the filter. Receiver center frequency of the output signal of the second mixer is characterized in that so as to coincide with the center frequency of the fourth filter regardless of the change. 5. A first device having a function of band-limiting a received signal
Filter, a first amplifying means having a function of amplifying an output signal of the first filter, a second filter having a function of band limiting the output signal of the first amplifying means, and a local oscillator. A first mixer having a function of inputting an output signal of the local oscillator and an output signal of a second filter to perform frequency conversion, and a third filter having a function of band limiting the output signal of the first mixer A second local oscillator, a reference oscillator, and a function of dividing and phase comparing the output signals of the reference oscillator and the second local oscillator to phase lock the second local oscillator to an arbitrary oscillation frequency. A PLL synthesizer having the second mixer, a second mixer having a function of performing frequency conversion by inputting the output signal of the third filter and the output signal of the signal generating means, and an output signal of the second mixer. A fourth filter having a function of band limiting, a second amplifier having a function of amplifying an output signal of the fourth filter, and a demodulation unit having a function of inputting and demodulating an output signal of the second amplifier. In a receiver including: a temperature detection unit having a function of detecting an ambient temperature; a storage unit having a function of storing a setting value of the PLL synthesizer; and a control unit having a function of setting the PLL synthesizer. The control means stores the set value of the PLL synthesizer in which the center frequency of the output signal of the second mixer and the center frequency of the fourth filter match in the storage means according to the ambient temperature, and receives the set value. Sometimes the set value of the PLL synthesizer is read from the storage means according to the ambient temperature detected by the temperature detection means, Controlling so that the PLL synthesizer is set so that the center frequency of the output signal of the second mixer is closest to the center frequency of the fourth filter regardless of changes in ambient temperature. Machine. 6. A first device having a function of band-limiting a received signal.
Filter, a first amplifying means having a function of amplifying an output signal of the first filter, a second filter having a function of band limiting the output signal of the first amplifying means, and a local oscillator. A first mixer having a function of inputting an output signal of the local oscillator and an output signal of a second filter to perform frequency conversion, and a third filter having a function of band limiting the output signal of the first mixer A second local oscillator, a reference oscillator, and a function of dividing and phase comparing the output signals of the reference oscillator and the second local oscillator to phase lock the second local oscillator to an arbitrary oscillation frequency. A PLL synthesizer having the second mixer, a second mixer having a function of performing frequency conversion by inputting the output signal of the third filter and the output signal of the signal generating means, and an output signal of the second mixer. A fourth filter having a function of band limiting, a second amplifier having a function of amplifying an output signal of the fourth filter, and a demodulation unit having a function of inputting and demodulating an output signal of the second amplifier. In a receiver including: a temperature detection unit having a function of detecting an ambient temperature; a storage unit having a function of storing a setting value of the PLL synthesizer; and a control unit having a function of setting the PLL synthesizer. The control means stores the set value of the PLL synthesizer at an arbitrary reference temperature in the storage means,
Change amount of the center frequency of the filter is stored in the storage unit according to the ambient temperature, and the change amount of the center frequency of the fourth filter is stored in the storage unit according to the ambient temperature detected by the temperature detecting unit during reception. The oscillation frequency of the signal generating means is controlled by using the set value of the PLL synthesizer at the reference temperature and the change amount of the read center frequency of the filter at the reference temperature. The receiver is characterized in that the center frequency of the output signal of the second mixer is closest to the center frequency of the fourth filter. 7. A radiotelephone comprising the receiver according to claim 1, 2, 3, 4, 5 or 6. 8. A wireless communication device comprising the receiver according to claim 1, 2, 3, 4, 5 or 6.