Device and method for providing time switched transmission diversity in mobile communication system

A code division multiple access (CDMA) mobile communication system, comprising:

• a signal generator for generating a modulation signal by modulating +1 or −1 signal with a code having predetermined code length;
• first and second transmit antennas;
• first and second RF transmitters, each of the RF transmitters coupled to a respective one of the antennas, for converting the signal generated by the signal generator to an RF signal and outputting the RF signal through the respective antennas;
• a time switching transmission controller for switching the transmission signal to one of the RF transmitters in order to performing time switched transmission diversity(TSTD), wherein the switching cycle is an integer multiple of the code length;
• a receiver for receiving the RF signal transmitted through the antennas, the receiver at least comprising first pilot demodulator for estimating a phase of the first pilot signal transmitted through the first antenna and second pilot demodulator for estimating a phase of the second pilot signal transmitted from the second antenna;
• a controller for alternatively selecting the first estimated phase or the second estimated phase according to the switching cycle to support the TSTD reception;
• and
• a demodulator for detecting the modulation signal with the first estimated phase or the second estimated phase according to the selection of the controller.

A code division multiple access (CDMA) channel signal transmitting method in a CDMA mobile communication system, comprising the steps of:

• generating a modulation signal by modulating +1 or −1 signal with a code having predetermined code length;
• switching the modulation signal to a first RF transmitter connected to a first antenna or a second RF transmitter connected to a second antenna with non-overlapping time intervals;
• and
• converting the modulation signal to a radio frequency(RF) signal to transmitting the RF signal through one of the antennas, wherein a cycle of the switching is an integer multiple of the code length.

A channel signal receiving method in a code division multiple access (CDMA) mobile communication system, comprising the steps of:

• generating a modulation signal by modulating +1 or −1 signal with a code having predetermined code length;
• switching the modulation signal to a first RF transmitter connected to a first antenna or a second RF transmitter connected to a second antenna with non-overlapping time intervals;
• converting the modulation signal to a radio frequency(RF) signal to transmitting the RF signal through one of the antennas, wherein a cycle of the switching is an integer multiple of the code length;
• receiving the RF signal transmitted through the antennas;
• estimating a phase of the first pilot signal transmitted through the first antenna and a phase of the second pilot signal transmitted from the second antenna;
• alternatively selecting the first estimated phase or the second estimated phase according to the switching cycle to support the TSTD reception;
• and
• detecting the modulation signal with the first estimated phase or the second estimated phase according to the selection.

A transmitting apparatus in a code division multiple access (CDMA) mobile communication system, comprising:

• a signal generator for generating a transmission signal by modulating +1 or −1 signal with a code having predetermined code length;
• two or more transmit antennas;
• two or more RF transmitters, each of the RF transmitters connected to a respective one of the antennas, for converting the signal generated by the signal generator to an RF signal and outputting the RF signal through the respective antenna;
• and
• a time switching transmission controller for alternately switching the transmission signal to one of the RF transmitters for a fixed, non-overlapping predetermined time unit to provide time switching transmission diversity (TSTD),
• wherein the switching cycle of the controller is an integer multiple of the code length.

A transmitting method in a code division multiple access (CDMA) mobile communication base station system, having two or more antennas and two or more RF transmitters, each of the RF transmitters connected to a respective one of the antennas for converting an input signal to an RF signal and outputting the RF signal through the respective antenna, comprising the steps of:

• generating a transmission signal by modulating +1 or −1 signal with a code having predetermined code length;
• and
• transmitting the transmission signal to one of the RF transmitters for a predetermined time unit to provide time switching transmission diversity (TSTD) and transmitting the transmission signal,
• wherein the transmission cycle is an integer multiple of the code length.