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GB2324663A - PC monitoring of receiver level, A/D conversion and reception conditions - Google Patents

PC monitoring of receiver level, A/D conversion and reception conditions Download PDF

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Publication number
GB2324663A
GB2324663A GB9808472A GB9808472A GB2324663A GB 2324663 A GB2324663 A GB 2324663A GB 9808472 A GB9808472 A GB 9808472A GB 9808472 A GB9808472 A GB 9808472A GB 2324663 A GB2324663 A GB 2324663A
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GB
United Kingdom
Prior art keywords
radio
terminal device
receivable
radio terminal
electric field
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB9808472A
Other versions
GB9808472D0 (en
GB2324663B (en
Inventor
Katsuhiro Otsuka
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
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Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to GB0031685A priority Critical patent/GB2355609B/en
Publication of GB9808472D0 publication Critical patent/GB9808472D0/en
Publication of GB2324663A publication Critical patent/GB2324663A/en
Application granted granted Critical
Publication of GB2324663B publication Critical patent/GB2324663B/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03GCONTROL OF AMPLIFICATION
    • H03G3/00Gain control in amplifiers or frequency changers
    • H03G3/001Digital control of analog signals
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B17/00Monitoring; Testing
    • H04B17/30Monitoring; Testing of propagation channels
    • H04B17/309Measuring or estimating channel quality parameters
    • H04B17/318Received signal strength

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  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Transmission In General (AREA)
  • Circuits Of Receivers In General (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

A personal computer 1 controls adjustments of an associated radio section 6 and A/D converter 7. In particular an instruction is sent to the controller 10 to supply a reference signal to the A/D converter instead of the received signal. The output of the A/D converter is buffered in memory 8 before being transmitter to the personal computer. After this the personal computer instructs the controller to supply upper and lower bound signals from the signal generator 3 instead of the received signal. Related received signal strength indication (RSSI) signals are buffered in memory 8 before being transmitted to the personal computer. Using this information the personal computer calculates a threshold value for distinguishing between communicable and non-communicable radio areas.

Description

MnIOD OF ADJUSTING THE RECEIVABLE LEVEL OF AN ELECTRIC FIELD RECEIVABLE BY A RADIO TERMINAL DEVICE The present invention relates to a method of adjusting the receivable level of the electric field of a radio signal receivable by a radio terminal device.
A conventional radio terminal device is provided with a controller and a memory, as disclosed in Japanese Patent Laid-Open Publication No. 63-77275. In such a radio terminal device, first, the dispersion in RSSI (received signal strength indication) of a radio section and the correction of an analog-digital (A/D) converter are adjusted on assembling the device, and then the adjustment of a threshold value for discriminating between a communicable radio area and an uncommunicable radio area is conducted once. Thereafter, a threshold value level signal is input to the device to measure its value, and software within a memory is changed to complete the adjustment of the threshold value.
In this conventional adjusting method of the radio terminal device, it is difficult to adjust this device after assembly, and a problem in maintenance of the device arises when the device is used.
Accordingly, it is an object of at least the preferred embodiment of the present invention to provide a method of adjusting a level of a receivable electric field of a radio terminal device, in view of the aforementioned problem of the prior art, which is capable of carrying out adjustment of correction data of an A/D converter and dispersion of a radio section after assembling the device.
In a first aspect, the present invention provides a method of adjusting the receivable level of the electric field of a radio section receivable by a radio terminal device including an analog-digital converter and a radio section, said method comprising measuring correction data of the analog-digital converter and the dispersion of the receivable electric field level of the radio section in the radio terminal device, calculating outside of the radio terminal device a threshold value for discriminating between a communicable radio area and an uncommunicable radio area of the radio terminal device on the basis of the correction data of the analog-digital converter and the dispersion of the receivable electric field level, and utilising the calculation result in the radio terminal device.
In a preferred embodiment, an adjusting method of a receivable electric field level of a radio terminal device, including an A/D converter and a radio section, comprises the steps of measuring correction data (a value of a reference voltage corrected by the A/D converter when the reference voltage is converted thereby) of the A/D converter and dispersion of receivable electric field level of the radio section in the radio terminal device, calculating a threshold value for discriminating between a radio communicable area and a radio uncommunicable area outside of the radio terminal device on the basis of the correction data of the AID converter and the data of the dispersion of the receivable electric field level, and controlling the calculation result in the radio terminal device.
In one preferred embodiment, there is a personal computer for sending a command for measuring the correction data and a command for measuring the receivable electric field level to the radio terminal device when the radio terminal device measures the correction data and the dispersion of the receivable electric field level, collects measuring data and calculates the threshold value.
In another aspect, the present invention provides a system for adjusting the range of a radio section of a radio terminal device, preferably for use in adjusting a receivable electric field level of a radio terminal device, which comprises a personal computer, said radio terminal device being connected to the personal computer by means of a serial line, the radio terminal device including a power circuit connected to a power source for supplying an electric power voltage thereto, said radio section being coupled with a signal generator arranged to output a receivable level signal thereto, an analog-digital (A/D) converter, a memory, a serial port and a controller.
In another aspect, the present invention provides a method of measuring correction data for an analog-digital converter of a radio terminal device whilst adjusting the dispersion of a receivable level of the electric field of a radio signal receivable by said device, said method comprising the steps of receiving a command for measuring said correction data from a personal computer, stopping the operation of the radio terminal device, supplying a reference voltage to said A/D converter from a power circuit, converting the reference voltage into digital data and outputting said digital data to a memory of said device, storing temporarily the digital data in a memory, and reading the converted correction data from the memory and outputting said data to said personal computer.
In a preferred embodiment, a method of measuring a correction data for a radio terminal device at the time adjusting dispersion comprises the steps of receiving command for measuring a correction data of an A/D converter from a personal computer via a serial port, stopping operation of the radio terminal device by means of a controller, supplying a reference voltage to the A/D converter from a power circuit, converting the reference voltage into digital data to output this digital data to the controller before receiving the reference voltage by means of the A/D converter, storing temporarily the received data into a memory by means of the controller, and reading the measured converted correction data out of the memory and outputting this data to a personal computer via a serial port by means of the controller when there is no unmeasured data.
In yet another aspect, the present invention provides a method of measuring the dispersion of a receivable level of the electric field of a radio signal in a radio section of a radio terminal device and adjusting said dispersion, said method comprising the steps of receiving a command for adjusting said dispersion from a personal computer switching the radio section to an operative state in order to read a received signal strength indication (RSSI) thereof, receiving a signal representing the maximum value of the receivable electric field level and sending the RSSI value thereof to an A/D converter of the radio terminal device, converting said RSSI value into digital data, storing temporarily the digital data in a memory, and reading the stored data from the memory, and transmitting the stored data to said personal computer.
In a preferred embodiment, a method of measuring a dispersion of a receivable electric field level of the radio section for a radio terminal device at the time adjusting dispersion comprlses the steps of inputting a command for adjusting the dispersion of the receive electric field level from the personal computer - via the seria-l port, making the radio section operative in order to read the RSSI of the radio-section by means of a controller, receiving a signal representing the maximum value of the receive electric field level from. the signal generator and sending its RSSI value to the A/D converter by means of the radio section, converting the RSSI value into digital data and sending the converted data to the controller by means of the A/D converter, storing temporarily the received data into the memory by means of the controller, and reading the collected dispersin-data of the receive electric field level out of the memory, and sending the data to the personal computer via the serial port by means of the controller when there is no uncollected data.
According to the above, the adjustment of the dispersion of RSSI of the radio section and the correction of the A/D converter can be carried out from the outside of the radio terminal device and the radio terminal device controls only the result of the adjustment. Hence, the adjustment after the device assemble can be readily carried out, and in case that the radio section includes no signal adjusting means of the receive electric field level, the adjustment can be implemented.
Preferably, - a personal computer sends a command for measuring the correction data and a command for measuring the receive electric field level to the radio terminal device when the radio terminal device measures the correction. data and the dispersion of the receive electric field level, collects measuring data and calculates the threshold the threshold value. ~ Preferred features of the present invention will now be described, purely by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a block diagram of a measuring system for adjusting dispersion of a radie section of a radio termini device for use in a method of adjusting a level of receivable electric field -of a radio terminal device; Fig. 2 is a ~sequential representation stowing data flow between a personal computer and a radio terminal device Fig. 3 is a flow chart showing an operation of a method of adjusting a level of receivable electric field of a radio terminal device; Fig. 4 is a graphical representation showing an approximation curve of an electric field level in the adjusting method.
Referring now to the drawings, there is shown in Fig.
1 a measuring system for adjusting dispersion of a radio section of a radio terminal device for use in a method of adjusting a: level of. receiv ble electric field of a radio terminal device.
In Fig. 1, a personal computer 1 is connected to a radio terminal device 4 by a serial line. The radio terminal device 4 includes zit tower circuit 5 connected to a power source 2, a. radio section 6 coupled with a signal-generator 3, an analog-digital (A/D)-converter-7 7 for converting analog -values such as an RSSI value and a reference voltage-into their digital values, a memory 8, a serial port 9 and a controller 10. The power source 2 supplies an electric power voltage to the power circuit 5. The signal generator 3 outputs a receivable level signal to the radio section 6.
Fig. 2 shows data flow between a personal computer and a radio terminal device in the adjusting method.
Fig. 3 is a flow chart showing an operation of a method of adjusting a level of a receivable electric field of a radio terminal device.
Fig. 4 shows an - approximation curve of an electric field level.
In Fig. 2, when the personal computer sends a command for measuring correction data of the A/D converter 7 to the radio terminal device 4 in step 11, the radio terminal device 4 starts measuring the correction data of the A/D converter 7.
An operation of the measuring of correction data in the radio terminal device 4 will be described with reference to Fig. 3.
First, the controller 10 receives the command for measuring the correction data of the A/D converter 7 from the personal computer 1-via the serial-port 9 in step 21. The controller 10 stops the operation of the radio terminal device 4 in step 22, to supply the reference voltage to the A/D converter 7 from the power circuit 5 in step 23. After receipt of the reference voltage, the A/D converter 7 converts the reference voltage into digital data to output this digital data to the controller 10 in step 24. The controller 10 temporarily stores the received data into the memory in step 25; If there is unmeasured data, for example, the minimum reference voltage in step 26, steps 23 to 25 are executed again. When there is no unmeasured data in step 26, the controller 10 reads the measured converted correction data out of the memory 8 and outputs this data to the personal computer 1 via the serial port 9 in step 27.
The personal computer 1. stores the measured converted correction data in a memory within the personal computer 1.
The personal computer 1 then sends a command for measuring the dispersiorr of a. level out receivable electric field of the radio section 6 to-the radio terminal device 4. - Theradio terminal device 4 then measures the dispersion data of the radio section 6 arid sends the measured data to the pers-onal computer 1, as follows.
The radio terminal device 4 starts measuring in step 28 in Fig. 3 and the controller 10 inputs a command for adjusting the dispersion of the level of the receivable electric field from the personal computer 1 via the serial port 9. The controller 10 makes the radio section 6 operative in order to read the RSSI of the radio section 6 in step 29. The radio section 6 receives a signal representing the maximum value of the receivable electric field level from the signal generator 3 and sends its RSSI value to the A/D converter 7 in step 30.
The A/D converter 7 converts the RSSI value into digital data and sends the converted data to the controller 10 in step 31.
The controller 10 temporarily stores the received data into the memory 8 in step 32. When there are any uncollected data such as the minimum value of the receivable electric freld level in step 33, the controller 10 carries out steps 30 to 32 repeatedly. There ls no uncollected data in step 33, the controller 10 reads the collected dispersion data of the receivable electric field level out of the memory 8, and sends the data to the personal computer 1 via the serial port 9 in step 34.
The personal computer 1 calculates a threshold value for doscriminating~between a communicable radio . area and an uncommunicable radio area on the basis of the converted corrected data of the .A/D converter 7 and the dlspersion data of the receivable electric field level, and - -outputs the - calculaThedThhreshold value data to the radio terminal device 4 in step 15 in-Fig. 2.
When calculating the - threshold value for discriminating between the uncommunicable radio area and the uncommunicable radio area, the personal computer 1 uses the following formula.
y = a*x + b ............ (1) Formula (1) shows an electric field level approximation line, as shown in Fig. 4, taking the receivable electric field level in the y-axis direction and the reference voltage converted by the A/D converter 7 in the x-axis direction. In formula (1), a represents the slope of the electric field level approximation line and b represents the intercept against the taxis. - The personal computer 1 substitutes the value V2 obtained by converting the maximum reference voltage in the A/D converter 7 and the maximum value RSSImax of the receivable electric field level for x and y .in formula (1) to obtain the following formula.
RSSImax = a*V2 + b .*... (2) The personal computer 1-also substitutes the value V1 obtained by converting the minimum reference voltage -in the A/D converter 7 and the minimum value RSSImin of the -receivable electric field level for x and y in formula (1) to obtain the following formula.
RSSImin = a*V1 + b ..... (3) The personal computer 1 then eliminates the intercept b using the formulas (2) and (3) to obtain the slope a of the electric field level approximation line as-follows.
a -- (RSSImax - RSSImin) / (V2 --VI) ... (4) The personal computer~ 1 substitutes the slope a of formula (4) for the slope a in formula (3) to obtain the intercept b as follows.
b = RSSImin - a*V1~ (5) The personal computer 1 substitutes the obtained slope a of the electric field level approximation line, the intercept b against the y-axis, and the value of the electric field level y -for discriminating between the communicable radio area and the uncommunicable radio area for those in formula (1) to obtain the value x. That is, the threshold value Vn for discriminating between the communicable radio area and the uncommunicable radio - area is calculated as follows.
-Vn = (RSSI area discrimination level - b)/a .. (6) The personal computer 1 sends the obtained threshold value Vn using formula (6) to the radio terminal device 4 via the serial port 9.
In the radio terminal device 4, the controller 10 receives - the threshold value Vn from the personal computer 1 via the serial port 9 in step 35 in Fig. 3. The controller 10 then stores the threshold value Vn into the memory 8 in step 36 to complete the. adjustment operation.
As described above, in a method of adjusting a receivable electric field level of a radio terminal device, the following advantages can be obtained.
(1) A correction of RSSI dispersion of the radio section, a correction value measuring of the A/D converter can be carried out from the outside of the radio terminal device, and only a threshold value for discriminating between a - radio communicable area and an unconrmunicable radio - area can be controlled inthe radio terminal device. As a result, the adjustment after the device assembly can be readily performed.
(2) - In case that the radio section includes no signal adjusting means of the receivable electric field level, the adjustment can be carried out.
While the present invention has been described in its preferred embodiments with reference to the accompanying drawings, it will be appreciated that various changes and modifications can be made by those skilled in the art without departing from the spirit and scope of the present invention.
Each feature disclosed in this specification (which term includes the claims) and/or shown in the drawings may be incorporated in the invention independently of other disclosed and/or illustrated features.
The text of the abstract filed herewith is repeated below as part of the specification.
A method of adjusting a level of a receivable electric field of a radio terminal device including an analog-digital converter and a radio section. The radio terminal device measures correction data of the analog-digital converter and dispersion of a receivable electric field level of the radio section upon receipt of a command from a personal computer. The adjustment of the correction data of the analog-digital converter and the dispersion data of the receivable electric field level is implemented outside of the radio terminal device. The personal computer calculates a threshold value for discriminating between a communicable radio area and an uncommunicable radio area on the basis of the correction data of the analog-digital converter and the dispersion data-of the receivable electric field level to send the threshold value to the radio terminal device. The radio terminal device stores the threshold value in a memory.

Claims (8)

1. A method of adjusting the receivable level of the electric field of a radio signal receivable by a radio terminal device including an analog-digital converter and a radio section, said method comprising: measuring correction data of the analog-digital converter and the dispersion of the receivable electric field level of the radio section in the radio terminal device; calculating outside of the radio terminal device a threshold value for discriminating between a communicable radio area and an uncommunicable radio area of the radio terminal device on the basis of the correction data of the analog-digital converter and the dispersion of the receivable electric field level; and utilising the calculation result in the radio terminal device.
2. A method according to Claim 1, wherein a command for measuring the correction data and a command for measuring the receivable electric field level are output to the radio terminal device from a personal computer when the radio terminal device measures the correction data and the dispersion of the receivable electric field level, said personal computer receiving the measuring data and calculating the threshold value.
3. A system for adjusting the receivable level of the electric field of a radio signal receivable by a radio terminal device including an analog-digital converter and a radio section, said system comprising: means for measuring correction data of the analog-digital converter and the dispersion of the receivable electric field level of the radio section in the radio terminal device; means for calculating outside of the radio terminal device a threshold value for discriminating between a communicable radio area and an uncommunicable radio area of the radio terminal device on the basis of the correction data of the analog digital converter and the dispersion of the receivable electric field level; and means for utilising the calculation result in the radio terminal device.
4. A method of measuring correction data for an analog-digital converter of a radio terminal device whilst adjusting the dispersion of a receivable level of the electric field of a radio signal receivable by said device, said method comprising the steps of: receiving a command for measuring said correction data from a personal computer; stopping the operation of the radio terminal device; supplying a reference voltage to said A/O converter from a power circuit; converting the reference voltage into digital data and outputting said digital data to a memory of said device; storing temporarily the digital data in said memory; and reading the converted correction data from the memory and outputting said data to said personal computer.
5. A method of measuring the dispersion of a receivable level of the electric field of a radio signal in a radio section of a radio terminal device and adjusting said dispersion, said method comprising the steps of: receiving a command for adjusting said dispersion from a personal computer; switching the radio section to an operative state in order to read a received signal strength indication (RSSI) thereof; receiving a signal representing the maximum value of the receivable electric field level and sending the RSSI value thereof to an A/D converter of the radio terminal device; converting said RSSl value into digital data; storing temporarily the digital data in a memory, reading the stored data from the memory, and sending the data to the personal computer.
6. A system for measuring the dispersion of a receivable level of the electric field of a radio signal in a radio section of a radio terminal device and adjusting the said dispersion, said system comprising: a personal computer; said radio terminal device comprising a serial port for receiving a command for adjusting said dispersion; control means for switching the radio section to an operative state in order to read a received signal strength indication (RSSI) thereof; a signal generator, said radio section being arranged to receive a signal representing the maximum value of the receivable electric field level from said signal generator and sending the RSSI value thereof to an A/I) converter of the radio terminal device; said A/D converter being adapted to convert said RSSI value into digital data and output the converted data to the control means; and said control means being arranged to store temporarily the digital data in a memory, read the stored data from the memory, and send the data to said personal computer via the serial port.
7. A system for adjusting the dispersion of a radio section of a radio terminal device, comprising: a personal computer, said radio terminal device being connected to said personal computer by means of a serial line; said radio terminal device comprising: a power circuit connected to a power source for supplying an electric power voltage thereto; said radio section being coupled to a signal generator for outputting a receivable signal level thereto; an analog-digital (A/D) converter for converting an analog receivable signal strength identification value and a reference voltage to respective digital values; a memory; a serial port; and a controller.
8. A method or system for adjusting the receivable level of the electric field of a radio signal receivable by a radio terminal device, for measuring correction data, or for measuring the dispersion level of said radio signal substantially as herein described.
GB9808472A 1997-04-21 1998-04-21 Method of adjusting the receivable level of an electric field receivable by a radio terminal device Expired - Fee Related GB2324663B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB0031685A GB2355609B (en) 1997-04-21 1998-04-21 Method of adjusting the receivable level of an electric field receivable by a radio terminal device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9103228A JPH10294696A (en) 1997-04-21 1997-04-21 Method for adjusting reception electric field level of wireless terminal

Publications (3)

Publication Number Publication Date
GB9808472D0 GB9808472D0 (en) 1998-06-17
GB2324663A true GB2324663A (en) 1998-10-28
GB2324663B GB2324663B (en) 2001-03-28

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GB9808472A Expired - Fee Related GB2324663B (en) 1997-04-21 1998-04-21 Method of adjusting the receivable level of an electric field receivable by a radio terminal device

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JP (1) JPH10294696A (en)
AU (1) AU737673B2 (en)
GB (1) GB2324663B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4090601B2 (en) * 1998-12-16 2008-05-28 パナソニック コミュニケーションズ株式会社 Wireless communication apparatus and wireless communication system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2199711A (en) * 1987-01-08 1988-07-13 Schlumberger Electronics Converter calibration
US5555277A (en) * 1993-12-01 1996-09-10 Datapoint Corporation Technique for cancelling common mode switching noise to achieve reduced error rates in a local area network

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI108765B (en) * 1993-09-28 2002-03-15 Nokia Corp Method and apparatus for measuring gain errors in the receiver of a base station in a cellular radio system and for specifying the field strength measurement

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2199711A (en) * 1987-01-08 1988-07-13 Schlumberger Electronics Converter calibration
US5555277A (en) * 1993-12-01 1996-09-10 Datapoint Corporation Technique for cancelling common mode switching noise to achieve reduced error rates in a local area network

Also Published As

Publication number Publication date
GB9808472D0 (en) 1998-06-17
GB2324663B (en) 2001-03-28
AU737673B2 (en) 2001-08-30
AU6350298A (en) 1998-10-22
JPH10294696A (en) 1998-11-04

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 20020421