JPS62262529A - Radio selective call receiver - Google Patents

Abstract

PURPOSE:To always obtain the best reception state by using a turning capacitance selection circuit of a reception circuit so as to select a turning capacitance and a resistor corresponding to the length of a band antenna. CONSTITUTION:When the band is optimized in non-carrying state so as to obtain the high sensitivity even at the non-carrying state in a wrist watch type selective call receiver utilizing the band as the antenna, the turning capacitance is adjusted by a capacitor C3, and the value Q is adjusted by a combined resistance of resistors R2, RT14, ..., RTn5. When the band antenna, however, is put on a wrist, the inductance of the antenna is changed, the turning point is deviated and the value Q is lowered. An antenna length recognizing means 12 recognizes the length of band based on the physical contact at the carrying and the result is sent to a control circuit 13. The control circuit 13 selects a required capacitor from turning capacitors CT1-CTn of the turning circuit in order to correct in an optimum state the frequency characteristic of the turning circuit depending on the recognized antenna length turns on switching elements 10-11 to increase the capacitance thereby matching the turning frequency to the sent frequency.

Description

[Detailed description of the invention] [Industrial application field] The great invention is the arm! Leap 1- for Terakei type wireless selective call receiver.

In particular, it relates to adjusting the tuning capacitance and Q value of a damaged circuit.

[Conventional technology]

Conventionally, there is a wrist IPF type wireless selective call receiver (K).

Changes in the state of the Mononoke receiver that uses the band as a receiving antenna, such as when it arrives at @, when it does not arrive, and when it does not arrive at IC.
However, the length and inductance of the antenna itself will vary due to individual differences in the thickness of the user's arms. Inevitably, the tuning point of the receiving circuit also shifts, and in conventional receivers, the Q of the tuning circuit.

The deviation of the synchronization point was covered by a block that made the oscillation smaller.

[Invention f1″ - Trying to solve the problem] Only 2.
In the conventional receiver, since the Q+ of the tuning circuit is made small, the gain available to the receiving circuit at the true tuning point is also small. This will degrade the reception sensitivity5.
Connects to car.

Therefore, the present invention is intended to solve these problems, and its purpose is to change the tuning in an odd manner according to changes in antenna length, that is, changes in inductance, regardless of the thickness of the arm. The object of the present invention is to provide a wristwatch type wireless selective reception 1 using a band antenna, which can obtain the best sensitivity h.

[Means for solving the problem] *The wireless selective calling receiver of the invention utilizes a watch band as a receiving antenna for selective calling reception on the front line for receiving a selective calling number and message information. In a wristwatch-type radio selective calling receiver, the change in the length of the band antenna, that is, the inductance (corresponding to [7]) is made possible by having a tuning capacity selection circuit in the receiving circuit.

[Effect]

4. Effects of the present invention: In the case where the length of the band antenna changes according to the thickness of the user's arm, the changed length of the antenna is determined by means of determining the length of the band antenna. When the length of the band antenna changes, the impedance of the antenna also changes, so the tuning point h of the receiving circuit
It will shift by t. Therefore, the tuning capacitance selection circuit of the receiving circuit selects the tuning capacitance and resistance corresponding to the length, so that the best reception state with the latency h can be obtained regardless of the thickness of the user's arm.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a receiving circuit for radio selective calling 2-channel communication using an embodiment of the present invention, where BO2 indicates the relationship between the receiving frequency and the output from the receiving circuit. . 1 is the basis of wristwatches.1. It is a band 7 sotena, and 3.
6.7 is the IWl adjustment official size for receiving frequency selection. The current value can be received by Q of 2.4° and the resistance of 5 is set to 2. (1) The transmission frequency f+ of the system is sent from the transmitter to the non-Q forward selective calling receiver.
/I; Sent.

A signal at a frequency f of the receiver is received by a 1-band antenna and transmitted to an amplifying means 14.The signal amplified by the amplifying means 14 is transmitted to a subsequent signal processing circuit.

The frequency characteristics of a receiving circuit tuned to frequency f1 and having a necessary Q value are shown at 15 in Figure 2. In the case of the wristwatch-type wireless selective calling receiver used in the Pandoya antenna, a high electric shock of +11S can be obtained even when the user is not wearing the device, so it is possible to receive a high electric shock even when the user is not wearing the device.
When the maximum length is set, the tuning capacity t is adjusted by 3:C,
Q only 2:R,,4:BT.

......, 5: Adjusted by the combined resistance of RTn. However, when the band antenna is worn on the arm KM, the inductance ht of the antenna changes, so the tuning element h
t2: Rs, 4R 1.5R? ? +, joint agreement and 3:
When Ct is input, the frequency characteristic of the tuning circuit becomes as shown in Figure 2, and the tuning point shifts to a frequency lower than f+, which is the output of the transmitter, and the Q value also decreases, l, , ! cormorant.

Therefore, from the antenna length recognized by the band antenna length recognition means, 13: Control circuit 12: Select the control circuit for correcting the tuning characteristics. 10.1
The necessary switching elements are turned on from the first switching element. Mafc
Do not avoid a decrease in Q value 4: R+ ~ 5: Determine the optimal resistance value from Rrn and turn off the necessary rz switching element of 8.9. (2) The antenna length recognition means, P// The band length is recognized and transmitted to the control circuit by physical contact between the contact points provided on the entire hole of the lead and the multi-step contact point, which is the hole or stopper of the other punt.

(3) The antenna length recognition means corresponds to the length of the band and detects the fc value, character, and the length of the receiver body, which is the number, character, or memorandum in which the other stopper overlaps. The antenna length is recognized by inputting the input switch such as the R4 button or the like and the antenna length is transmitted to the control circuit.

@) The control circuit calculates the frequency characteristics of the tuning circuit from 16 to 15 in Figure 2 from the antenna length recognition means (the antenna length recognized by the antenna length), and determines the optimum frequency characteristics of the antenna. To correct this, select the required one from 1 to CTn using the tuning capacitor C of the tuning circuit and turn ON the switching cables 10 to 11 to increase the value of 6 and match the tuning frequency with the transmission frequency. Regarding the Q value, change the value from 16 to 15 in the 5r2 diagram, Q to the value, and the value to the resistance R.
? ,~R? , by selecting the necessary one and turning off the switching elements 8 to 9, the Q value adjustment resistance is reduced and the Q value is adjusted to the required value. [Effects of the Invention] As described above. According to the present invention, in a wristwatch-type GF line call reception using a band antenna, regardless of whether the receiver is worn or not, and regardless of the thickness of the user's arm ( Regardless of the condition, the optimal values for the tuning capacitance and Q value adjustment resistor are selected according to the inductance of the antenna, so the receiver is always in a state with the best sensitivity.
Itic9 can be done.

In addition, since the tuning capacitance, Q, and value adjustment resistance become 9 when the switching element is turned on and off, the adjustment elements 111'' such as the trimmer capacitor and volume are unnecessary.
In addition to improving productivity in factories, etc., it also reduces costs and prevents failures due to defects in the trimmer capacitor or volume itself.

In terms of antenna length recognition means, the antenna length A" is recognized at the junction of the bands, or the mark at the junction is recognized by manual labor, which is simple in terms of construction. This will lead to improved performance.There will be no design restrictions since existing band fittings and input terminals are used.

[Brief explanation of drawings]

FIG. 1 is a receiving circuit diagram of a radio selective calling receiver using an actual example of the present invention. Figure 2 is a diagram showing a frequency characteristic curve when the receiver is not worn on the arm and a frequency characteristic curve when the receiver is worn when the invention is not used. 1...Band antenna 2...Resistance for Q value adjustment 3...+Reliable wave number/penetration tuning capacitance 4...
...Resistor 5 for Q value adjustment...Resistor 6 for Q, value adjustment...Tune customer group 7 for receiving frequency selection...
- Tuning customer group for reception frequency selection 8...Switching element 9...Switching element 10...Switching element 11...Switching element 12... Antenna length approval means 13...Amplification means -
F Applicant: Seiko Epson Corporation Figure 1

Claims (1)

[Scope of Claims] (1) In a wristwatch-type wireless selective calling receiver that receives a selective calling number and message information and uses a wristwatch band as a receiving antenna, the receiving section includes an antenna and an antenna. length recognition means, at least two or more receiving frequency tuning capacitors, at least two or more Q value adjustment resistors, a switching element for switching the capacitors and the resistors, and an antenna length recognition means corresponding to the antenna length recognized by the antenna length recognition means. A radio selective call receiver comprising a control circuit that selects the capacitance and the resistance and turns on and off the switching element. (2) The antenna length recognition means includes a band hole or a stop metal part that is a multi-step contact point between the stop metal part of one band and the other band, which is used as a physical contact switch, and the signal from the stop metal part of the receiver. The radio selective calling receiver according to claim 1, characterized in that it is constituted by a transmitting section for transmitting information to a control circuit. (5) The antenna length recognition means includes a number corresponding to the length,
A band on which letters or symbols are displayed; the band has a hole or a stopper that matches the number, letter, or symbol; the number indicated on the band;
The radio selective calling receiver according to claim 1, characterized in that it is constituted by an input switch attached to the receiver body for inputting characters and symbols.