Semiconductor integrated circuit device and wireless communication system

Abstract

The dynamic range is changed by switching a current applied to an amplifying circuit to obtain the minimum ICP required to keep linearity with the number of multiplexes even when the number of multiplexes of data is changed by switching the operation current of the amplifying circuits of the transmission system and also supplying the information about number of multiplexes of data to be transmitted to the amplifying circuits of the transmission system from the baseband circuit. Thereby, the signal can be transmitted without distortion even when the number of multiplexes increases and the current of the amplifying circuit may be reduced when the number of multiplexes is small in order to reduce the current consumption in the communication semiconductor integrated circuit device which can form a wireless communication system of the code division multiplex system such as W-CDMA system.

Description

[0001] The present application is a continuation of application Ser. No. 10 / 685,481, filed Oct. 16, 2003, the contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION [0002] The present invention relates to a wireless communication technology, more specifically to a technology which may be effectively applied, while increase of power consumption is controlled, for improving linearity of a semiconductor integrated circuit device comprising an amplifying circuit to amplify the code division multiplexed transmitting signal. Moreover, the present invention relates to a technology which may be effectively applied to a semiconductor integrated circuit device for communication constituting a wireless communication device, for example, of W-CDMA (Wideband Code Division Multiple Access) system and to a wireless communication device such as a mobile telephone or the like comprising the same semiconductor integrated circuit device. [0003] In the wireless communication...

AI Technical Summary

Benefits of technology

"The patent text describes a problem in the transmission system of a mobile phone in the W-CDMA system. When multiple signals are transmitted simultaneously, the peak factor (the difference between the maximum power and the average output level) increases, causing distortion and degraded performance. The inventors have designed an amplifying circuit with a wider dynamic range to avoid distortion and improve performance. The invention aims to solve this problem in a mobile phone while reducing current consumption and extending battery life."

Problems solved by technology

In the specification of the mobile telephone of the W-CDMA system, it is specified that the data of six channels in maximum can be transmitted from one channel through the multiplexing, but this method has problems that the more the number of multiplexes of data is increased, the more the distortion of transmission signal increases and thereby the ACPR (leak power ratio to the adjacent channel) characteristic is deteriorated.

Moreover, it has been found when the transmission signal is amplified with an amplifying circuit having a narrower dynamic range with the peak factor which is large as described above, distortion of signal increases and the ACPR characteristic is deteriorated.

However, since power consumption of the total system increases when the current of the amplifying circuit increases, it is a problem to be eliminated as much as possible in the system such as a mobile telephone which is operated with a battery.

However, in the mobile telephone of the W-CDMA system, since the transmitting operation and receiving operation are executed simultaneously and continuously, current consumption is considerably larger than that of the mobile telephone of the PDC system.

Therefore, increase in current of the amplifying circuit in the mobile telephone of the W-CDMA system will result in the problem that the maximum communication time and the maximum waiting time which are intrinsically short may be further shortened.

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