| 摘要 |
<p>Radio-signal direction finding is performed in the following manner. There is a plurality of antennas (A) at different locations. A switchable antenna coupler (SAC) switches (SW) from one antenna (A[i]) being coupled to a radio-signal input (INP), to another antenna (A[i+1]) being coupled to the radio-signal input (INP). A radio-signal processor (ASP) processes a radio signal (AS) which is present at the radio-signal input (INP) so as to obtain a phase-detection input signal (PDIS). A phase-change detector (PCD) detects a phase change (Δζ) in the phase-detection input signal (PDIS) due to the switching (SW) from the one antenna (A[i]) to the other antenna (A[i+1]). A calculator (CAL) calculates the direction (DIR) of the radio-signal source (SRC) on the basis of this phase change (Δζ). This manner of performing radio-signal finding can be implemented at relatively modest cost because it requires only one radio-signal processor. It is particularly suitable for use in a wireless communication apparatus, for example, to select the antenna which will provide the best signal quality.</p> |
