Transmitting device and transmitting method

Abstract

In a modulation method in which a sender device expresses a symbol such as an 8PSK or a 16PSK by using three or more bits, important information is arranged at least at only one of the first and second bits, a receiver device extracts the important information from at least one of the first and second bits of the received signal, and thereby communication control is carried out based on the important information.

Description

[0001] This application is a divisional application of an invention patent application with a filing date of November 8, 1999, an application number of 99801989.5, and an invention title of "transmitting and receiving device and transmitting and receiving method". technical field [0002] The present invention relates to a transmitting device and a transmitting method, in particular to a transmitting and receiving device for Orthogonal Frequency Division Multiplexing (hereinafter referred to as an "OFDM transmitting and receiving device"). Background technique [0003] Below, refer to figure 1 A conventional OFDM transmitting and receiving device will be described. figure 1 It is a structural block diagram of an existing OFDM transmitting and receiving device. [0004] refer to figure 1 , a parallel / serial converter (hereinafter referred to as "P / S converter") 101 inserts important information into transmission data. This important information refers to information that m...

AI Technical Summary

Problems solved by technology

[0018] Here, in the case where retransmission information is used as important information, when the error rate characteristic of the retransmission information in the receiving-side device deteriorates as described above, the number of times the transmitting-side device retransmits the retransmission information increases, so the completion of communication time growth

Usually, the number of retransmissions of a certain information is limited, and if the retransmission is not completed within this number of times, the error correction of the information cannot be performed

Therefore, in the case of image communication that requires very good error characteristics, it is impossible to maintain normal communication

[0019] Also, when information indicating the current modulation method is used as important information, when the error rate characteristic of the information deteriorates at the receiving end, it becomes difficult for the receiving end to recognize the modulation method used at the sending end, so the signal transmitted from the sending end cannot be received

Therefore, between the sending end and the receiving end, normal communication cannot be maintained

Images