JP2002330068A - Communication equipment and frequency adjusting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide communication equipment and a frequency adjusting method capable of automatically and easily correcting a frequency error gradually increasing with lapse of time. SOLUTION: This communication equipment is provided with a non-volatile storage medium 16 for storing a synthesizer frequency error ΔfSYN detected by a digital signal processor 15. The synthesizer frequency error ΔfSYN stored in the non-volatile storage medium 16 is removed from a frequency set value fSYN at the time of previous start by a digital signal processor 15, and a frequency set value fSYN-ΔfSYN at the time of the next start is outputted to a frequency synthesizer 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system for simply correcting a frequency error that changes slowly over a long period of time, such as an initial frequency error of a reference frequency oscillator provided therein or a frequency error due to aging. The present invention relates to an apparatus and a frequency adjustment method.

[0002]

2. Description of the Related Art FIG. 9 is a diagram showing a configuration of a reference frequency oscillator. In FIG. 9, 101 is a crystal oscillator, 102
A and 102B are C-MOS inverting amplifiers, respectively, and 103B.
A and 103B are capacitors, respectively, and 104 is a resistor. In the reference frequency oscillator shown in FIG.
Is used as a trimmer to change the capacitance, thereby adjusting the oscillating reference frequency.

FIG. 10 is a diagram showing a configuration of a conventional communication device, and particularly shows a receiving section provided in the communication device. In FIG. 10A, 111 is a reference frequency oscillator, 112 is a frequency synthesizer whose frequency can be set by a digital signal, 113 is a mixer for frequency down-conversion, 114 is an A / D converter, and 115 performs demodulation processing and the like. It is a digital signal processor.

In accordance with the frequency f _STD + Δf _STD of the reference signal from the reference frequency oscillator 111 and the frequency set value f _SYN from the digital signal processor 115, the frequency synthesizer 112 outputs a synthesizer signal of the frequency f _SYN + Δf _SYN. . Here, f _STD and Δf _STD are a reference frequency and a reference frequency error of the reference frequency oscillator 111, respectively, and f _SYN and Δf _SYN are a synthesizer frequency and a synthesizer frequency error of the frequency synthesizer 112, respectively. Synthesizer frequency error Δf
_SYN is caused by a reference frequency error Delta] f _STD, the reference frequency error Delta] f _STD is due to such an initial frequency error or aging of the reference frequency oscillator 111.

The digital signal processor 115 has an automatic frequency for automatically controlling the frequency.
ncy Control function (AFC function) and frequency sweep function to change frequency setting value (SWP function)
The frequency error estimation range (AFC range) by the AFC function is [-f _AFCLMT , + f _AFCLMT ], SWP
The range in which the frequency can be swept by the function (SWP range) is [−f _SWPLMT , + f _{SW PLMT} ]. Where f
_{It is assumed that AFCLMT} <f _SWPLMT (FIG. 10B).

Next, the operation will be described. FIG. 11 is a flowchart showing a conventional frequency adjustment method. Frequency f _SYN output from frequency synthesizer 112 + Δf _SYN
Is mixed by the mixer 113 with the reception signal of the reception frequency f _{C in} the RF / IF band (step S
T101), the mixer 113 outputs a baseband signal of the frequency f _B + Δf _SYN to the A / D converter 114 (step ST102). However, f _B is the baseband frequency, is f _B = f _C -f _SYN.

The frequency f _B + Δf is calculated by the A / D converter 114.
_When the A / D conversion processing of the _SYN baseband signal is performed, the digital signal processor 115 corrects the synthesizer frequency error Δf _SYN by the AFC function or the SWP function.

For example, | Δf_SYN| <F_AFCLMTlike,
Synthesizer frequency error Δf_SYNIs within the AFC range
(YES in step ST103), digital signal processing
Unit 115 performs frequency error estimation by the AFC function.
Synthesizer frequency error Δf _SYNDetect and synthesize
The frequency error Δf_SYNFrequency synthesizer
Control the receiver 112 to synchronize with the received signal (step
ST104).

After step ST104, the communication apparatus of FIG. 10 enters a standby state (step ST106), and performs mixing at the next startup at the synthesizer frequency f _SYN (steps ST107 to ST101).

[0010] The reference frequency error Δf _STD is increased | Δf
_SYN |> f _AFCLMT , and synthesizer frequency error Δf
_{Even if the SYN} does not fall within the AFC range (NO in step _ST103 ), if the synthesizer frequency error Δf _SYN is in the SWP range as | Δf _SYN | <f _SWPLMT (YES in step ST108), the synthesizer The digital signal processor 115 sweeps the frequency of the frequency synthesizer 112 so that the frequency error Δf _SYN is approximately canceled by the SWP function (step ST10).
9).

[0011] by the frequency sweep | Δf _SYN | <f
_{When the AFCLMT} is reached, the operation of step ST104 described above is performed, and the digital signal processor 115 detects the synthesizer frequency error Δf _SYN and synchronizes with the received signal (step ST104). Thereafter, steps ST106, ST
Continues to the operation of 107~ST101, mixing of the next startup is also performed in the synthesizer frequency f _SYN.

The reference frequency error Δf _STD further increases, and the synthesizer frequency error Δf _SYN becomes considerably large.
Δf _SWPLMT <| Δf _SYN | AFC range, SWP
If it is out of the range (step ST103)
, NO in step ST108), the AFC function and the SWP function of the digital signal processor 115 do not work, and the communication device becomes unusable and requires maintenance adjustment (step ST110).

In the maintenance adjustment in step ST110, the reference
Reference frequency f of frequency oscillator 111 _STDTo adjust
The housing of the communication device is opened, and the capacitor described in FIG.
Complicated work such as adjustment using the 103A as a trimmer is required.
To the electronic components on the substrate of the reference frequency oscillator 111.
Because of direct contact, workers and workplaces are limited.
U.

[0014]

Since the conventional frequency adjustment method is configured as described above, there is a problem that a frequency error that gradually increases due to aging cannot be automatically and simply corrected. Was.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a communication apparatus and a frequency adjustment method capable of automatically and simply correcting a frequency error gradually increasing with time. It is intended to constitute.

[0016]

A communication device according to the present invention includes a nonvolatile storage medium for storing a synthesizer frequency error detected by a digital signal processor, and digitally stores the synthesizer frequency error stored in the nonvolatile storage medium. The signal processor removes the frequency setting value from the frequency setting value and sets the frequency setting value for the next reception.

A communication device according to the present invention includes a request input device for transmitting a request to a digital signal processor by a user operation, and when a request from the request input device is transmitted, the digital signal processor detects a synthesizer frequency error. Then, the data is stored in a nonvolatile storage medium.

In the communication device according to the present invention, when a request from the request input device is transmitted, the digital signal processor recognizes the maintenance adjustment mode and expands the sweep range of the frequency setting value.

A communication apparatus according to the present invention provides a second frequency synthesizer that outputs a second synthesizer signal according to a frequency of a reference signal and a second frequency set value, and mixes the second synthesizer signal with a second baseband signal. A second mixer that outputs a transmission signal through a digital signal processor, and an external device that determines the stop / movement state of the own station and transmits the stop signal to the digital signal processor. A frequency error is detected and stored in a non-volatile storage medium, and the digital signal processor removes the synthesizer frequency error and the second synthesizer frequency error stored in the non-volatile storage medium from the frequency set value and the second frequency set value, respectively. , The frequency setting value for the next reception and the second frequency setting value.

A communication apparatus according to the present invention provides a second frequency synthesizer that outputs a second synthesizer signal according to a frequency of a reference signal and a second frequency set value, and mixes the second synthesizer signal with a second baseband signal. A second mixer for outputting a transmission signal by a user and a request input device for transmitting a request to the digital signal processor by a user operation. When the request is transmitted from the request input device, the digital signal processor detects a synthesizer frequency error. The digital signal processor removes the synthesizer frequency error and the second synthesizer frequency error stored in the nonvolatile storage medium from the frequency set value and the second frequency set value. And the second frequency set value.

According to the frequency adjusting method of the present invention, a synthesizer signal output from a frequency synthesizer is mixed with a received signal in accordance with a frequency of a reference signal from a reference signal oscillator and a frequency set value from a digital signal processor. A mixing step of outputting a baseband signal, A / D conversion of the baseband signal, detection of a synthesizer frequency error of the synthesizer signal, and control of the frequency synthesizer so as to cancel the synthesizer frequency error to synchronize with the received signal. A frequency error detection / synchronization step, a frequency error storage step of storing the synthesizer frequency error detected in the frequency error detection / synchronization step in a nonvolatile storage medium, and a synthesizer frequency error stored in the nonvolatile storage medium from the frequency setting value. Remove and save at next startup Is obtained by so and a frequency setting value correction step of a frequency setting value.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a diagram illustrating a configuration of a communication device according to a first embodiment of the present invention, and particularly illustrates a receiving unit provided in the communication device. In FIG. 1, 11 is a reference frequency oscillator, 12 is a frequency synthesizer whose frequency can be set by a digital signal, 13 is a mixer for frequency down-conversion, 14 is an A / D converter, and 15 is digital signal processing for performing demodulation processing and the like. The storage device 16 is a non-volatile storage medium that retains its stored contents even when the power of the communication device is turned off.

As in the prior art, the frequency synthesizer 12 adjusts the frequency f _SYN + Δf _SYN according to the frequency f _STD + Δf _{ST D} of the reference signal from the reference frequency oscillator 11 and the frequency set value f _SYN from the digital signal processor 15. Output the synthesizer signal. Here, f _STD and Δf _STD are a reference frequency and a reference frequency error of the reference frequency oscillator 11, respectively, and f _SYN and Δf _SYN are a synthesizer frequency and a synthesizer frequency error of the frequency synthesizer 12, respectively. Synthesizer frequency error Δ
f _SYN is caused by a reference frequency error Delta] f _STD, the reference frequency error Delta] f _STD is due to such an initial frequency error or aging of the reference frequency oscillator 11.

The digital signal processor 15 also has an AFC function and a SWP function as in the prior art.
The range is [-f _AFCLMT , + f _AFCLMT ] and the SWP range is [-
f _{SW PLMT} , + f _SWPLMT ]. Where f _AFCLMT
<F _SWPLMT

Next, the operation will be described. FIG. 2 is a flowchart showing a frequency adjustment method according to Embodiment 1 of the present invention. The reference signal of the frequency f _SYN + Δf _SYN output from the frequency synthesizer 12 is mixed with the reception signal of the reception frequency f _{C in} the RF / IF band by the mixer 13 (step ST1), and the mixer 13 outputs the frequency f _B + Δ.
The baseband signal of f _SYN is output to the A / D converter 14 (step ST2). However, f _B is the baseband frequency, is f _B = f _C -f _SYN.

The frequency f _B + Δf _{SYN in the} A / D converter 14
After the A / D conversion of the baseband signal is performed, the digital signal processor 15 corrects the synthesizer frequency error Δf _SYN by the AFC function or the SWP function.

For example, | Δf _SYN | <f _AFCLMT
If the synthesizer frequency error Δf _SYN is within the AFC range (YES in step ST3), the digital signal processor 1
Reference _numeral 5 denotes a frequency synthesizer 1 which performs frequency error estimation by the AFC function, detects a synthesizer frequency error Δf _SYN, and cancels the synthesizer frequency error Δf _SYN.
2 to synchronize with the received signal (step ST
4).

In the first embodiment, step S
At T5, the digital signal processor 15 stores the synthesizer frequency error Δf _SYN detected in step ST4 in the nonvolatile storage medium 16. Synthesizer frequency error Δf stored in nonvolatile storage medium 16
_In consideration of the _SYN , mixing at the next startup is performed.

That is, after the standby state in step ST6, the digital signal processor 15 sets the frequency set value for the frequency synthesizer 12 to f _SYN -Δf _SYN .
An operation is performed to perform the next mixing (step S
T7).

Thus, the frequency setting at the time of the previous
Constant value f_SYNSynthesizer detected and remembered at the last boot from
The frequency error Δf_SYNTo remove the frequency setting for the next startup.
Constant value f_SYN-Δf_SYNThe frequency at the next start-up
The number synthesizer 12 has a reference frequency f_STD+ Δf_STDTo
And synthesizer frequency f_SYNTo the mixer 13
And the digital signal is transmitted in step ST4.
The synthesizer frequency error detected by the signal processor 15 is 0.
Becomes the reference frequency error Δf due to aging. _STDShadow of
The sound can be canceled.

Of course, the synthesizer frequency error 0 detected in this case is stored in the non-volatile storage medium 16, and the frequency set value (f _SYN −Δf _SYN ) −0 = f _SYN for the frequency synthesizer 12 at the time of successive startup. Outputs -Δf _SYN .

Reference frequency error Δf_STDIncreases and | Δf
_SYN|> F_AFCLMTAnd the synthesizer frequency error Δf
_SYNEven if it does not fall within the AFC range,
NO in step ST3), | Δf_SYN| <F_SWPLMTlike
Synthesizer frequency error Δf _SYNIs within the SWP range
If (YES in step ST8), the synthesizer frequency
Difference Δf_SYNTo be roughly canceled by SWP function
And the digital signal processor 15 is connected to the frequency synthesizer 12.
Is frequency-swept (step ST9).

By the frequency sweep, | Δf _SYN | <f
_{When AFCLMT} is _reached , the operation of step ST4 described above is performed, and the digital signal processor 15 detects the synthesizer frequency error Δf _SYN to synchronize with the received signal (step ST4), and as described above, detects the detected synthesizer frequency error. Δf _SYN is stored in the non-volatile storage medium 16 (step ST5). Thereafter, steps ST6, ST7 to ST
Subsequent to the operation 1, the mixing in step ST1 is performed at the synthesizer frequency f _SYN -Δf _SYN , so that the influence of the reference frequency error Δf _STD due to aging can be canceled.

By doing so, the reference frequency error gradually increasing with aging can be automatically and simply corrected by the above operation, and the time until the reception synchronization is established by the SWP function can be shortened. be able to.

The reference frequency error Δf _STD further increases, and the synthesizer frequency error Δf _SYN becomes considerably large.
Δf _SWPLMT <| Δf _SYN | AFC range, SWP
If it is out of the range (N in step ST3)
O, NO in step ST8), maintenance adjustment of the communication device is performed (step ST10). The maintenance adjustment will be described in a second embodiment.

[0036] As described above, according to the first embodiment, the provided non-volatile storage medium 16 for storing the detected synthesizer frequency error Delta] f _SYN digital signal processor 15, and stored in the nonvolatile storage medium 16 The digital signal processor 15 removes the synthesizer frequency error Δf _SYN from the frequency set value f _SYN and sets the frequency set value at the next reception to f _SYN −Δf _SYN. The effect that the frequency error Δf _STD can be automatically and simply corrected can be obtained, and the time until the reception synchronization is established by the frequency sweep operation can be shortened.

Further, according to the first embodiment, the frequency f _STD of the reference signal from the reference signal oscillator 11 + Δf _STD
And the frequency set value f from the digital signal processor 15
Mixing steps ST1 and ST for mixing a synthesizer signal output from frequency synthesizer 12 corresponding to _SYN and a received signal to output a baseband signal
2, the base band signal is A / D converted detected a synthesizer frequency error Delta] f _SYN with the synthesizer signal, a synthesizer frequency error received signal by controlling a frequency synthesizer 12 so as Delta] f cancel the _SYN and synchronization frequency error The non-volatile storage medium 1 stores the synthesizer frequency error Δf _SYN detected in the detection and synchronization steps ST3 and ST4 and the frequency error detection and synchronization steps ST3 and ST4.
6 and the synthesizer frequency error Δf stored in the non-volatile storage medium 16.
_SYN is removed from the frequency set value f _SYN to set a frequency set value f _SYN −Δf _SYN at the next startup at a frequency set value correcting step ST7, so that the reference frequency error gradually increases with aging. The effect that Δf _STD can be automatically and simply corrected can be obtained.
The effect that the time until the reception synchronization is established by the frequency sweep operation can be shortened is obtained.

Embodiment 2 In the first embodiment, the synthesizer frequency error Δf _SYN is stored in the non-volatile storage medium 16 every time it is started up. However, when a user requests, the synthesizer frequency error Δf _SYN is stored in the non-volatile storage medium 16. May be stored.

FIG. 3 is a diagram showing a configuration of a communication device according to the second embodiment of the present invention, and particularly illustrates a receiving unit provided in the communication device. 1 have the same or corresponding configurations. In FIG. 3, reference numeral 17 denotes an external button (request input device) for transmitting a user request to the digital signal processor 15 by a user operation.

When the user presses the external button 17, the digital signal processor 15 stores the synthesizer frequency error Δf _SYN in the nonvolatile storage medium 16. Hereinafter, the same operation as in the first embodiment is performed, and the same effect as in the first embodiment is obtained.

At this time, if the digital signal processor 15 recognizes that the communication device is not in the normal operation mode but in the maintenance adjustment mode (step ST10) of FIG. 2, the normal operation mode may be limited by specifications. This is effective for expanding the SWP range [−f _SWPLMT , + f _SWPLMT ] and correcting a frequency error due to a larger aging.

This is because the user does not use the communication device for a long time and the reference frequency oscillator 11 changes over time.
Synthesizer frequency error Δf of frequency synthesizer 12
_{Even when SYN} exceeds [−f _SWPLMT , + f _SWPLMT ], the frequency can be corrected.

As described above, according to the second embodiment, the external button 17 for transmitting a request to the digital signal processor 15 by the operation of the user is provided, and when the request from the external button 17 is transmitted, the digital signal processing is performed. Since the synthesizer 15 detects the synthesizer frequency error Δf _SYN and stores it in the non-volatile storage medium 16, the reference frequency error Δf _SYN gradually increasing with time can be manually and simply corrected. Is obtained, and the time until the reception synchronization is established by the frequency sweep operation can be shortened.

According to the second embodiment, the external button
When the request from the button 17 is transmitted, digital signal processing is performed.
The switch 15 recognizes the maintenance adjustment mode and switches the frequency set value.
Frequency synthesizer
Synthesizer frequency error Δf of the 12_SYNIs in normal operation mode
Variable range [-f_SWPLMT, + F
_SWPLMT] Also performs frequency correction when it exceeds
The effect that it can be obtained is obtained.

Embodiment 3 Embodiments 1 and 2 assume that a large Doppler frequency is not applied to the reception frequency f _C of the communication device. In order to apply the first and second embodiments to a mobile station that moves at a high speed such that the Doppler frequency cannot be ignored, it is necessary to previously separate the frequency error of the communication device of the mobile station from the Doppler frequency.

FIG. 4 is a diagram showing a mobile station Y moving at a high speed toward a stationary base station X. First, correction of the Doppler frequency when there is no frequency error due to aging in the state of FIG. 4 will be described.

FIG. 5 shows that the reference frequency error Δf _STD is
FIG. 7 is a diagram for explaining Doppler frequency correction in a case where the frequency is not present. In the state shown in FIG. 4, when the transmission frequency f _C is transmitted from the base station X to the mobile station Y (FIG. 5A), the mobile station Y
Then, for the transmission frequency f _C , the Doppler frequency + Δf
_DPL is applied and received (FIG. 5B).

On the other hand, since the Doppler frequency + Δf _DPL ′ is similarly applied to the transmission frequency f _C ′ from the mobile station Y, the mobile station Y transmits the transmission frequency as f _C ′ −Δf _DPL ′ (FIG. 5). (C)), the base station X can receive the frequency f _C ′ from which the Doppler frequency Δf _DPL ′ has been removed (FIG. 5D).

Next, the reference frequency error Δf due to aging
_{The case} where the mobile station Y corrects the Doppler frequency while the _STD is included in the reference frequency f will be described.

FIG. 6 shows that the reference frequency error Δf _STD is
FIG. 7 is a diagram for explaining Doppler frequency correction in the case of the above. In the state of FIG. 4, even if the Doppler frequency Δf _DPL is applied to the reception of the mobile station Y, the mobile station Y generates the frequency f _C + Δf by the synthesizer frequency error Δf _SYN .
Because it is with reference to the _SYN, the Doppler frequency Δf
_It is erroneously recognized as _DPL- Δf _SYN (FIG. 6B).

At this time, the transmitting unit of the mobile station Y operates at the frequency f
_{Since the} transmission frequency is corrected by Δf _DPL '−Δf _SYN ' based on _C '+ Δf _SYN ' and transmitted (FIG. 6C), the base station X uses a reception frequency including a frequency error of 2Δf _SYN '. It will be received (FIG. 6D).

To prevent the above errors, the transmission and reception
Number error is Δf_SYN’, Δf_SYNAnd send
The reference of mobile station Y in each reception is f_C’+ Δf
_SYN’, F_C+ Δf_SYNFrom -Δf_SYN’, −Δf_SYN
Is corrected only as shown in FIG. _C’, F_CMove to position
Need to be done.

FIG. 7 shows communication according to the third embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration of an apparatus. The same reference numerals as those in FIG.
Is an equivalent configuration. In FIG. 7, 12 'is for transmission.
Frequency synthesizer (second frequency synthesizer), 1
3 'is a transmission mixer (second mixer), 18 is a mobile station Y
External device (stop / stop) that identifies the stop / moving state of (own station)
Movement determiner). In FIG. 7, the Doppler frequency is supplemented.
The frequency is corrected by the digital signal processor 15 to correct
Set value f _SYN, The second frequency set value f_SYN’
Prepare the frequency synthesizers 12, 12 '
The transmission and reception frequencies are controlled independently.

Next, the operation will be described. External device 18
Obtains the speed information of the mobile station Y from the outside, and determines that the mobile station Y is stopped if the speed of the mobile station Y is equal to or less than the threshold value. When the external device 18 determines that the mobile station Y is in the stopped state, the received signal f _C input to the mixer 13 does not include the Doppler frequency Δf _DPL , and thus the synthesizer detected by the digital signal processor 15 is used. Frequency error Δf _SYN
Can be determined to be due to the reference frequency error Δf _STD .

At this time, the synthesizer of the frequency synthesizer 12
The synthesizer frequency error Δf_SYNTo the nonvolatile storage medium 16
In addition to memorizing, as described in FIG.
Each frequency set value for the synthesizers 12, 12 'is represented by f_SYN
-Δf_SYN, F_SYN′ -Δf _SYN’
(The second frequency synthesizer error Δf_SYN’Is a synthesizer
Isa frequency error Δf_SYN), Reception frequency f_C,
Transmission frequency f_C’With no frequency error
X can communicate with it.

The external device 18 obtains the speed information of the mobile station Y from the outside, and determines that the mobile station Y is in the moving state if the speed of the mobile station Y is equal to or higher than the threshold. If the external device 18 determines that the mobile station Y is moving, the reception frequency f _C input to the mixer 13 includes the Doppler frequency Δf _DPL
And the reference frequency error Δf _SYN cannot be detected.

[0057] In this case, the mobile station Y synthesizer frequency error Delta] f _{SY N} detected previously stopped reading from the nonvolatile storage medium 16, thereby the respective frequency setting value for the frequency synthesizer 12, 12 'f _SYN -.DELTA.f
_SYN, by correcting respectively f _SYN '-Δf _SYN', the receiving frequency f _C, without including the frequency error to the transmission frequency f _C ', can communicate with base station X.

As described above, according to the third embodiment,
If the frequency f of the reference signal_STD+ Δf_{ST D}And second frequency
Number setting value Δf_SYN′ To output the second synthesizer signal.
A second frequency synthesizer 12 '
The second baseband signal (frequency f_B’) And Mi
Kiss to transmit signal (frequency f_C’)
The mixer 13 'and the stop / moving state of the mobile station Y are determined.
An external device 18 for transmitting to the digital signal processor 15 is provided.
When the stop state is transmitted from the external device 18, the digital
Signal processor 15 has synthesizer frequency error Δf_SYNTo
Detected and stored in the non-volatile storage medium 16,
Synthesizer frequency error Δf stored in medium 16_SYNYou
And second synthesizer frequency error Δf_SYN’
Constant value f_SYNAnd the second frequency set value Δf_SYNFrom '
Signal signals are removed by the
Each of the frequency set value and the second frequency set value is f_SYN
-Δf _SYN , F_SYN′ -Δf_SYN’
Therefore, in the mobile station Y moving at high speed, the Doppler frequency
Number Δf_DPL, Δf_DPL′ And the reference frequency error Δf_STDAnd
Automatically corrects frequency errors separately
The effect is obtained.

Embodiment 4 FIG. In the third embodiment, it is assumed that the mobile station Y moving at high speed has an external device for identifying the stop / moving state of the mobile station Y. 17 may be substituted.

FIG. 8 is a diagram showing a configuration of a communication device according to the fourth embodiment of the present invention. The same reference numerals as those in FIGS. 1, 2, and 3 denote the same or corresponding components. The communication device of FIG.
An external button (request input device) 17 is connected to the digital signal processor 15 on the assumption that there is no external device 18 for determining the stop / movement state.

The external button 17 has a reference frequency f_STD
Is pressed when the user requests correction of
You. The user determines that the mobile station Y is in the stopped state,
When the external button 17 is pressed, the digital signal processor 15
Is the synthesizer frequency error Δf _SYNIs non-volatile
While being stored in the storage medium 16, the reception frequency f_C, Send
Signal frequency f_C′ To −Δf_SYN, -Δf_SYN’
Communication can be performed without frequency error.

When the user has not pressed the external button 17, the Δf detected by the previous button press is
_{The SYN} is read from the non-volatile storage medium 16, and the reception frequency f _C and the transmission frequency f _C ′ are set to −Δf _SYN , −
By correcting each of Δf _SYN ′, communication can be performed without a frequency error.

As described above, according to the fourth embodiment, the second frequency synthesizer 12 that outputs the second synthesizer signal in accordance with the frequency f _STD + Δf _{ST D} of the reference signal and the second frequency set value f _SYN ′. , A second mixer 13 for mixing the second synthesizer signal with the second baseband signal and outputting a transmission signal, and an external button 1 for transmitting a request to the digital signal processor 15 by a user operation.
When the request is transmitted from the external button 17,
The digital signal processor 15 calculates the synthesizer frequency error Δf
_SYN is detected and stored in the nonvolatile storage medium 16, and the synthesizer frequency error Δf stored in the nonvolatile storage medium 16
_The digital signal processor 15 removes the _SYN and the second synthesizer frequency error Δf _SYN ′ from the frequency set value f _SYN and the second frequency set value Δf _SYN ′, respectively, and sets the frequency set value and the second frequency set value at the next reception. To f _SYN −
Since Δf _SYN , f _SYN ′ −Δf _SYN ′, the Doppler frequencies Δf _DPL , Δf _DPL ′ and the reference frequency error Δf _STD are separated without requiring the external device 18 in the mobile station Y moving at high speed. This makes it possible to correct the frequency error.

[0064]

As described above, according to the present invention, a non-volatile storage medium for storing a synthesizer frequency error detected by a digital signal processor is provided, and the synthesizer frequency error stored in the non-volatile storage medium is converted to a digital signal. The processor removes it from the frequency setting value and sets it as the frequency setting value for the next reception, so that the effect of automatically and simply correcting the reference frequency error that gradually increases with aging can be corrected. Thus, there is an effect that the time until the reception synchronization is established by the frequency sweep operation can be shortened.

According to the present invention, there is provided a request input device for transmitting a request to the digital signal processor by a user operation,
When a request from the request input device is transmitted, the digital signal processor detects the synthesizer frequency error and stores it in the non-volatile storage medium. And the time until the reception synchronization is established by the frequency sweep operation can be shortened.

According to the present invention, when the request from the request input device is transmitted, the digital signal processor recognizes the maintenance adjustment mode and expands the sweep range of the frequency set value. Therefore, the synthesizer of the frequency synthesizer is provided. Even when the frequency error exceeds the variable range of the frequency set value in the normal operation mode, the frequency correction can be performed.

According to the present invention, the second frequency synthesizer for outputting the second synthesizer signal in accordance with the frequency of the reference signal and the second frequency set value, and the second synthesizer signal is mixed with the second baseband signal and transmitted. A second mixer for outputting a signal; and an external device for judging a stopped / moving state of the own station and transmitting the signal to the digital signal processor. When the stopped state is transmitted from the external device, the digital signal processor causes a synthesizer frequency error. And the digital signal processor removes the synthesizer frequency error and the second synthesizer frequency error stored in the non-volatile storage medium from the frequency set value and the second frequency set value, respectively. Since the frequency setting value at the time of reception and the second frequency setting value are used, the station which moves at a high speed has It separates the error frequency and the reference frequency error there is an effect that it is possible to automatically correct the frequency error.

According to the present invention, the second frequency synthesizer that outputs the second synthesizer signal according to the frequency of the reference signal and the second frequency set value, and the second synthesizer signal is mixed with the second baseband signal and transmitted. A second mixer for outputting a signal; and a request input device for transmitting a request to the digital signal processor by a user operation. When the request is transmitted from the request input device, the digital signal processor detects a synthesizer frequency error and The digital signal processor removes the synthesizer frequency error and the second synthesizer frequency error stored in the nonvolatile storage medium from the frequency set value and the second frequency set value, respectively. Since the set value and the second frequency set value are used, an external device can be connected to the high-speed moving own station. There is an effect that no, it is possible to correct the frequency error by separating the Doppler frequency and the reference frequency error to.

According to the present invention, the synthesizer signal output from the frequency synthesizer and the received signal are mixed according to the frequency of the reference signal from the reference signal oscillator and the frequency set value from the digital signal processor, and A mixing step of outputting a signal, and A / D conversion of the baseband signal to detect a synthesizer frequency error of the synthesizer signal, and control the frequency synthesizer to cancel the synthesizer frequency error to synchronize with the received signal. A detection / synchronization step, a frequency error storage step of storing the synthesizer frequency error detected in the frequency error detection / synchronization step in a non-volatile storage medium, and removing the synthesizer frequency error stored in the non-volatile storage medium from the frequency setting value. Frequency setting value at next startup The frequency set value correction step is performed so that the reference frequency error gradually increasing with aging can be automatically and simply corrected, and until the reception synchronization is established by the frequency sweep operation. This has the effect of shortening the time.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a communication device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing a frequency adjustment method according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a communication device according to a second embodiment of the present invention.

FIG. 4 is a diagram illustrating a state of a mobile station moving at high speed toward a stationary base station.

FIG. 5 is a diagram for explaining Doppler frequency correction when there is no reference frequency error in a mobile station.

FIG. 6 is a diagram for explaining Doppler frequency correction when a reference frequency error exists in a mobile station.

FIG. 7 is a diagram showing a configuration of a communication device according to a third embodiment of the present invention.

FIG. 8 is a diagram showing a configuration of a communication device according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing a configuration of a reference frequency oscillator.

FIG. 10 is a diagram illustrating a configuration of a conventional communication device.

FIG. 11 is a flowchart illustrating a conventional frequency adjustment method.

[Explanation of symbols]

11 Reference frequency oscillator, 12, 12 'frequency synthesizer, 13, 13' mixer, 14 A / D converter, 1
5 digital signal processor, 16 non-volatile storage medium, 1
7 external button (request input device), 18 external device (stop movement judgment device), 101 crystal oscillator, 102A, 102
BC-MOS inverting amplifier, 103A, 103B capacitor, 104 resistor, 111 reference frequency oscillator, 1
12 frequency synthesizer, 113 mixer, 114 A
/ D converter, 115 digital signal processor.

Claims (6)

[Claims] 1. A reference frequency oscillator for outputting a reference signal, a frequency synthesizer for outputting a synthesizer signal according to a frequency and a frequency set value of the reference signal, and a baseband signal obtained by mixing the synthesizer signal with a reception signal. A mixer for outputting the frequency setting value to the frequency synthesizer, and A / D conversion of the baseband signal to detect a synthesizer frequency error included in the synthesizer signal, and to cancel the synthesizer frequency error. A communication device comprising: a digital signal processor that controls a frequency synthesizer to synchronize with a received signal; a non-volatile storage medium that stores the synthesizer frequency error detected by the digital signal processor; The processor is provided in the nonvolatile storage medium. The synthesizer frequency error and 憶 removed from the frequency setting value, the communication apparatus characterized by the above frequency setting value of the next received time. 2. A request input device for transmitting a request to a digital signal processor by an operation of a user, wherein the digital signal processor detects a synthesizer frequency error when receiving a request from the request input device, and performs non-volatile operation. The communication device according to claim 1, wherein the communication device is stored in a volatile storage medium. 3. The communication apparatus according to claim 2, wherein the digital signal processor recognizes the maintenance adjustment mode and expands the sweep range of the frequency set value when the request from the request input device is transmitted. . 4. A second frequency synthesizer for outputting a second synthesizer signal according to a frequency of a reference signal and a second frequency set value, and a transmission signal is output by mixing the second synthesizer signal with a second baseband signal. A digital mixer that determines the stopped / moving state of the own station and transmits the determined signal to the digital signal processor. The digital signal processor transmits the synthesizer frequency when the stopped state is transmitted from the external device. An error is detected and stored in a non-volatile storage medium, and the synthesizer frequency error and the second synthesizer frequency error stored in the non-volatile storage medium are removed from the frequency set value and the second frequency set value, respectively. 2. The communication apparatus according to claim 1, wherein the frequency setting value and the second frequency setting value at the time are set. 5. A second frequency synthesizer for outputting a second synthesizer signal in accordance with a frequency of a reference signal and a second frequency set value, and a transmission signal is output by mixing the second synthesizer signal with a second baseband signal. And a request input device for transmitting a request to the digital signal processor by a user operation. The digital signal processor detects a synthesizer frequency error when the request is transmitted from the request input device. And the synthesizer frequency error and the second synthesizer frequency error stored in the non-volatile storage medium are removed from the frequency set value and the second frequency set value, respectively. 2. The communication device according to claim 1, wherein the communication device sets a frequency setting value and the second frequency setting value. 6. A synthesizer signal output from a frequency synthesizer and a received signal are mixed according to a frequency of a reference signal from a reference signal oscillator and a frequency set value from a digital signal processor, and a baseband signal is output. A mixing step, A / D converting the baseband signal, detecting a synthesizer frequency error of the synthesizer signal, controlling the frequency synthesizer to cancel the synthesizer frequency error, and synchronizing with the received signal. A detection / synchronization step; a frequency error storage step of storing the synthesizer frequency error detected in the frequency error detection / synchronization step in a non-volatile storage medium; and a frequency setting value of the synthesizer frequency error stored in the non-volatile storage medium. From the A frequency set value correcting step of setting a frequency set value to be used.