JPH0520020Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application This invention relates to a multi-band radio communication device, and particularly to a radio communication device in which a transmission filter provided for each band is switched by a relay.

(b) Problems to be solved by prior art/devices Conventionally, in multi-band wireless communication devices that can emit frequencies in multiple frequency bands, the transmission filter provided for each band has been switched using a relay. What has been done is known.

However, in wireless communication devices that have a memory scan function that sequentially scans the operating frequencies stored in the memory, the transmission output stage and the transmission filter are connected via a relay every time a memory scan is performed. The disadvantage was that the relay operated violently during scanning, and the sound of this operation became harsh.

This invention was made in view of the above-mentioned points, and its purpose is to provide a wireless communication device in which relay switching noise is reduced.

(c) Means for solving the problem The wireless communication device of this invention comprises a memory for storing the operating frequencies of wireless communication, a memory scanning means for scanning the frequencies stored in this memory, at least one transmission output stage, a plurality of low-pass filters connected to this transmission output stage, and a plurality of relays provided between the transmission output stage and the plurality of low-pass filters, and further comprises relay control means for controlling the relays so that the transmission output stage and the low-pass filters are not connected while the memory scanning means is scanning the memory.

(D) Effect According to this invention, a memory for storing operating frequencies of wireless communication, a memory scanning means for scanning the frequencies stored in the memory, at least one transmission output stage, and a transmission output stage for the transmission output stage are provided. In a wireless transmitter comprising a plurality of connected low-pass filters and a plurality of relays provided between the transmission output stage and the plurality of low-pass filters, while the memory scanning means is scanning the memory, the transmission is not performed. Since the relay control means is provided to control the relay so that the output stage and the low-pass filter are not connected, there is no switching operation of the relay during memory scanning.

Therefore, the relay switching noise is eliminated.

(E) Embodiment An embodiment of the wireless communication device according to this invention will be explained based on FIG. 1.

In the figure, reference numeral 1 denotes a memory for storing the operating frequency of the wireless communication device, 2 denotes a scan switch for operating a memory scan function for scanning the frequency data stored in memory 1, 3 denotes a microcomputer for controlling this wireless communication device, 4 denotes a dial for switching and selecting the operating frequency, 5 denotes a memory scan means provided in microcomputer 3, 6 denotes a relay control means for controlling the relay of the transmitting section provided in microcomputer 3, 7 denotes a key for storing frequency data in memory 1, and T denotes the transmitting section of this wireless communication device.

The transmitting section T also includes a transmitting output stage 8 and a low-pass filter 9 which is a transmitting filter provided for each band.
A, 9B, 9C, relays 10A, 10B, 10C provided between the transmission output stage 8 and the low-pass filters 9A, 9B, 9C, and between the low-pass filters 9A, 9B, 9C and the antenna output terminal 11. It is composed of relays 12A, 12B, and 12C provided.

And relays 10A, 10B, 10C, 12
A, 12B, and 12C are controlled by relay control means 6, and while frequency data in memory 1 is being scanned by memory scanning means 5, relay 10 is controlled by relay control means 6.
A, 10B, 10C, 12A, 12B, and 12C are designed to cut off the circuit, and only when the memory scan is stopped, a desired low-pass filter based on the frequency data selected from the memory 1 is applied to the transmission output stage 8. relays 10A, 10B,
It controls 10C, 12A, 12B, and 12C.

Therefore, the high frequency power obtained at the transmission output stage 8 is transmitted to the antenna output terminal 1 via, for example, a relay 10A, a low-pass filter 9A, and a relay 12A.
I am guided by 1.

Next, the operation of this wireless communication device will be explained.

When the scan switch 2 is pressed, the memory scan means 5 starts operating, and each relay 10A, 10
B, 10C, 12A, 12B, and 12C are in an off (blocked) state.

Then, when the memory scan starts, frequency data is read from the memory 1 and this frequency is received for a certain period of time based on a timer (not shown).

The above operations are repeated during memory scanning, but the user can switch scan switch 2 based on the received status.
Press again to stop the memory scan operation. When the memory scan operation stops, appropriate relays are turned on (conducting) based on the selected frequency data.

Note that when the memory channel is switched using the dial 4, the frequency data in the memory 1 is read out and only the relay of the corresponding band is operated.

The relays 10A and 10 are connected so that the high frequency power of the transmission output stage 8 is guided to the antenna terminal 11.
B, 10C, 12A, 12B, and 12C are controlled.

The dial 4 may be configured by other means such as UP/DOWN keys.

(F) Effects of the invention Since the wireless communication device according to this invention is configured as described above, there is no relay switching noise.

In addition, it has excellent features such as a simple structure, low cost, and easy implementation.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of this wireless communication device. Explanation of main symbols: 1...Memory, 2...Scan switch, 3...Microcomputer, 4...
...Dial, 5...Memory scan means, 6...
Relay control means, 7...key, 8...transmission output stage, 9A, 9B, 9C...low pass filter, 1
0A, 10B, 10C, 12A, 12B, 12C
...Relay, 11...Antenna output terminal.

Claims (1)

[Claims for Utility Model Registration] A memory that stores operating frequencies for wireless communication, memory scanning means that scans the frequencies stored in this memory, at least one transmission output stage, and a device connected to this transmission output stage. In a wireless communication device comprising a plurality of low-pass filters and a plurality of relays provided between the transmission output stage and the plurality of low-pass filters, while the memory scanning means is scanning the memory, the transmission output stage is 1. A wireless communication device, further comprising a relay control means for controlling the relay so that the relay and the low-pass filter are not connected to each other.