Telecommunications – Receiver or analog modulated signal frequency converter – Signal selection based on frequency
Reexamination Certificate
1997-10-24
2001-07-17
Maung, Nay (Department: 2681)
Telecommunications
Receiver or analog modulated signal frequency converter
Signal selection based on frequency
C455S352000, C380S262000
Reexamination Certificate
active
06263197
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a transceiver for a vehicle and a transmitting-receiving method of the transceiver for a vehicle, and more particularly to a transceiver for a vehicle and a transmitting-receiving method thereof used for remote control for unlocking a vehicle door or the like.
BACKGROUND TECHNOLOGY
Conventionally, in a transceiver for a vehicle which is used for remote control for unlocking a vehicle door or the like, a transceiver for a vehicle for preventing a vehicle theft or the like is known. An example thereof is disclosed in Japanese Patent Application Laid-Open (JP-A) No. 4-336185.
As shown in
FIG. 6
, in this transceiver for a vehicle, data including a variable code (which is also called a rolling code) corresponding to a number of times of operation (i.e., the total number of times a transmitter
70
is operated) is transmitted from the transmitter
70
, which is provided at a wireless door lock remote controller, to a receiver
72
provided at a vehicle. At the receiver
72
, when a fixed code of the received data matches the code of the receiver
72
and the rolling code and the number of times of receipt matches each other, specifically, when the rolling code of the transmitter
70
and the value of a rolling counter of the receiver
72
, which is synchronous with the rolling code match, the receiver
72
receives the transmitted data. Accordingly, for example, when another person operates the transmitter
70
several times without pointing the same toward the vehicle, and thereafter operates the transmitter
70
while pointing the same toward the receiver
72
of the vehicle, because the rolling code and the number of times of receipt do not match, the receiver
72
does not receive the transmitted data However, when the owner of the vehicle operates the transmitter
70
several times while mistakenly riot pointing the same toward the vehicle, and thereafter operates the transmitter
70
while pointing the same toward the receiver
72
of the vehicle, the number of times of receipt by the receiver
72
is jump-updated by a predetermined operation (i.e., the number of times of receipt, which is the number of times the transmitter
70
was operated without being pointed toward the vehicle, is added) so that the receiver
72
can receive the transmitted data.
However, in this transceiver for a vehicle, when a battery of the transmitter becomes weak or the like, there is the possibility that transmission data into which an incorrect rolling code has been written may be generated at and transmitted by the transmitter. In this case, even if the number of times of receipt by the receiver
72
is jump-updated by a predetermined operation, there is the possibility that the rolling code and the number of times of receipt will not match.
In view of the aforementioned, it is an object of the present invention to provide a transceiver for a vehicle and a transmitting-receiving method thereof in which errors in the transmission of a rolling code can be prevented.
DISCLOSURE OF THE INVENTION
The present invention is a transceiver for a vehicle, comprising: a transmitter including: an operation section; a data generating section for generating transmission data formed of a fixed code, a rolling code corresponding to a number of times of operation of the operation section, and transmission information; a modulation section for modulating the transmission data; and a transmission section for transmitting the modulated transmission data, and a receiver including: a receiving section for receiving the transmission data transmitted from the transmitter; a demodulation section for demodulating the received data; and a data decoding section for judging, on the basis of the fixed code and the rolling code, whether data may be received, wherein the transmitter has transmission data record means into which the transmitted transmission data is written, a plurality of rolling code data storing areas for storing current rolling code data and past rolling code data being provided within the transmission data record means, and on the basis thereof, the transmitter generates transmission data.
Further, the transmission data record means has a writing error check area for storing writing error check data which expresses whether a rolling code has been written correctly, and at the data generating section, it is judged whether rolling code data is correct on the basis of the writing error check data within the writing error check area, and on the basis of the judgment, one of current rolling code data and past rolling code data is read. When it is judged by the judgment that the rolling code data is correct, current rolling code data is read from the rolling code data storing area, and when it is judged by the judgment that the rolling code data is incorrect, past rolling code data is read from the rolling code data storing area.
Moreover, a transmitting-receiving method of a transceiver for a vehicle comprising the steps of: preparing a transceiver for a vehicle comprising: a transmitter including: an operation section; a data generating section for generating transmission data formed of a fixed code, a rolling code corresponding to the number of times of operation of the operation section, and transmission information; a modulation section for modulating the transmission data; a transmission section for transmitting the modulated transmission data; and transmission data record means having a writing error check area, for storing writing error check data expressing whether a rolling code has been written correctly, and a plurality of rolling code data storing areas, for storing current rolling code data and past rolling code data, the transmitted transmission data being written into the transmission data record means, and a receiver including: a receiving section for receiving the transmission data transmitted from the transmitter; a demodulation section for demodulating the received data; and a data decoding section for judging, on the basis of the fixed code and the rolling code, whether data may be received; reading the data recorded in the transmission data record means; judging at the data generating section whether data in the writing error check area is read correctly; reading one of current rolling code data and past rolling code data on the basis of the judgment; transmitting the read data via the modulation section and the transmission section; and receiving, by the receiver, the transmitted data.
In accordance with the transceiver for a vehicle and the transmitting-receiving method thereof of the present invention, when the transmitter transmits transmission data to the receiver, the transmitted rolling code data is written into the transmission data record means. During the writing operation, for example, when a battery becomes weak or the like and the rolling code data is therefore not written correctly, a writing error check data which expresses that the rolling code data has not been written correctly is stored in the writing error check area.
Next, when the transmitter transmits transmission data to the receiver, on the basis of the writing error check data in the writing error check area, it is judged whether the rolling code data is correct. At the data generating section, when it is judged that the rolling code data is correct, current rolling code data is read from the transmission data record means, and on the basis of the read data, transmission data is generated. When it is judged that the rolling code data is incorrect, past rolling code data is read from the transmission data record means, and on the basis of the read data, transmission data is generated. As a result, an excellent effect can be obtained that errors in the transmission of a rolling code can be prevented.
REFERENCES:
patent: 5369706 (1994-11-01), Latka
patent: 5563600 (1996-10-01), Miyake
patent: 5565812 (1996-10-01), Soenen
patent: 5598475 (1997-01-01), Soenen et al.
patent: 5646456 (1997-07-01), Udoh et al.
patent: 5646996 (1997-07-01), Latka
patent: 5661804 (1997-08-0
Noda Takahisa
Shibagaki Yuuzi
Umeda Fumio
Cole Thomas W.
Kabushiki Kaisha Tokai-Rika-Denki-Seisakusho
Maung Nay
Peabody LLP Nixon
Trinh Sonny
LandOfFree
Transmitter/receiver for a vehicle and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transmitter/receiver for a vehicle and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transmitter/receiver for a vehicle and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2566602