The method (2) of the above-described methods will be described next with reference to FIG. 8. In the arrangement shown in FIG. 8, advertisement information is transmitted from the plurality of antennas of the short-range wireless communication unit 157 that is the transmitting-side apparatus by a radio frame (AoD radio signal 803) in different periods. The radio frame here can also be a radio frame to which CTE is added, as shown in FIG. 5. However, a conventional radio frame or a radio frame of another form such as a radio frame of the Classic Bluetooth standard may be used. A radio frame including information other than advertisement information may be used for direction estimation. Here, for example, as shown in 810 of FIG. 8, the transmission period of the AoD radio signal 803 from the antenna 604 is set, and immediately after that, the transmission period of the AoD radio signal 803 from the antenna 605 is set. In this case, in the short-range wireless communication unit 157, no silent section is generated between the transmission of the AoD radio signal 803 from the antenna 604 and the transmission of the AoD radio signal 803 from the antenna 605. On the other hand, the short-range wireless communication unit 110 can receive these radio signals in a form as shown in 820 of FIG. 8. That is, since the signal transmitted from the antenna 605 arrives at the short-range wireless communication unit 110 with a delay via a path longer than that of the signal transmitted from the antenna 604, a silent section is generated between the signals. In addition, if the antenna 605 transmits the signal first, the signal transmitted from the antenna 604 arrives at the short-range wireless communication unit 110 before signal transmitted from the antenna 605 wholly arrives at the short-range wireless communication unit 110. If a silent section of a predetermined length is set after completion of the signal transmission period of the antenna 604, and the signal transmission period from the antenna 605 is then set, the silent section is observed longer than the predetermined length in the radio signal received by the short-range wireless communication unit 110. Similarly, if a silent section of a predetermined length is set after completion of the signal transmission period of the antenna 605, and the signal transmission period from the antenna 604 is then set, the silent section is observed shorter than the predetermined length in the radio signal received by the short-range wireless communication unit 110. In this way, the signals transmitted from the plurality of antennas are observed as the shift of timing according to the path lengths in the short-range wireless communication unit 110. Note that to observe the shift of timing, the short-range wireless communication unit 110 is notified, in advance, of scheduling information representing which antenna transmits a signal at which timing (by, for example, the short-range wireless communication unit 157 or another apparatus).