Antenna selection diversity apparatus and receiving method

An antenna selection diversity apparatus comprising:

• three or more antennas;
• an antenna information storage section that stores antenna gains of said three or more antennas as information indicating selection priority;
• a reception level measuring section that measures the reception level of an antenna in actual use selected within a period of a plurality of frames consecutively and the reception level of an antenna to be measured selected once at said period of a plurality of frames;
• a level averaging section that averages the reception level of the antenna in actual use measured by said reception level measuring section and the reception level of the antenna to be measured corresponding to a predetermined number of times respectively;
• and
• an antenna selection section that selects one of said three or more antennas as said antenna in actual use within a period of a plurality of frames consecutively according to said selection priority and selects one of a plurality of antennas on standby except said antenna in actual use as said antenna to be measured once at said period of a plurality of frames, said antenna selection section selecting said antenna to be measured as the antenna in actual use when a mean value of the reception level of said antenna in actual use calculated by said level averaging section is smaller than a mean value of the reception level of said antenna to be measured and selecting the next antenna to be measured according to said selection priority.

An antenna selection diversity apparatus comprising:

• three or more antennas;
• an antenna information storage section that stores antenna gains of said three or more antennas as information indicating selection priority;
• a reception level measuring section that measures the reception level of an antenna to be measured selected once at a period of a plurality of frames;
• a level averaging section that averages the reception level of the antenna to be measured measured by said reception level measuring section corresponding to a predetermined number of times;
• an antenna-in-actual-use reception level calculation section that calculates the reception levels of said antenna to be measured and the antenna in actual use at an AGC voltage value using a convergence AGC voltage and a reception level vs. AGC voltage characteristic provided beforehand during reception processing on the received signal of the antenna in actual use selected within a period of a plurality of frames consecutively;
• and
• an antenna selection section that selects one of said three or more antennas as the antenna in actual use within a period of a plurality of frames consecutively according to said selection priority and selects one of a plurality of antennas on standby except said antenna in actual use as said antenna to be measured once at said period of a plurality of frames, said antenna selection section selecting said antenna to be measured as the antenna in actual use when the calculated reception level of said antenna in actual use is smaller than a mean value of the reception level of said antenna to be measured and selecting the next antenna to be measured according to said selection priority.

An antenna selection diversity reception method comprising the steps of:

• storing antenna gains of three or more antennas as information indicating selection priority beforehand;
• selecting one of said three or more antennas as an antenna in actual use within a period of a plurality of frames consecutively according to said selection priority;
• measuring the reception levels of said antenna in actual use and said antenna to be measured by selecting one of a plurality of antennas on standby except said antenna in actual use as an antenna to be measured once at said period of a plurality of frames;
• monitoring whether the measured reception level of the antenna in actual use falls below the reception level of the antenna to be measured a predetermined number of times consecutively or not;
• selecting said antenna to be measured as the antenna in actual use when said case occurs consecutively;
• selecting the next antenna to be measured according to said selection priority;
• and
• changing the antenna to be measured according to said selection priority when said case does not occur said predetermined number of times consecutively.

An antenna selection diversity reception method comprising the steps of:

• storing antenna gains of three or more antennas as information indicating selection priority beforehand;
• selecting one of said three or more antennas as an antenna in actual use within a period of a plurality of frames consecutively according to said selection priority;
• measuring the reception levels of said antenna in actual use and said antenna to be measured by selecting one of a plurality of antennas on standby except said antenna in actual use as an antenna to be measured once at said period of a plurality of frames;
• averaging the measured reception level of the antenna in actual use and the reception level of the antenna to be measured corresponding to a predetermined number of times respectively;
• selecting said antenna to be measured as the antenna in actual use when a mean value of the reception level of said antenna in actual use is smaller than a mean value of the reception level of said antenna to be measured;
• and
• selecting the next antenna to be measured according to said selection priority.

An antenna selection diversity reception method comprising the steps of:

• storing antenna gains of three or more antennas as information indicating selection priority beforehand;
• selecting one of said three or more antennas as an antenna in actual use within a period of a plurality of frames consecutively according to said selection priority;
• measuring the reception level of said antenna to be measured by selecting one of a plurality of antennas on standby except said antenna in actual use as an antenna to be measured once at said period of a plurality of frames;
• averaging the measured reception level of the antenna to be measured corresponding to a predetermined number of times;
• calculating the reception levels of said antenna to be measured and said antenna in actual use at an AGC voltage value using a convergence AGC voltage and a reception level vs. AGC voltage characteristic provided beforehand during reception processing on the received signal of said antenna in actual use selected within a period of a plurality of frames consecutively;
• selecting said antenna to be measured as the antenna in actual use when the calculated reception level of said antenna in actual use is smaller than a mean value of the reception level of said antenna to be measured;
• and
• selecting the next antenna to be measured according to said selection priority.