摘要 |
<p>A transmit/receive circuit for each of the antenna elements of a radar phased array including an optical fiber true time delay circuit responsive to an electrical RF signal for providing an optical signal having a controlled time delay, an optical fiber for propagating the time delay controlled optical signal, an optical detector circuit responsive to the propagated time delay controlled optical signal for providing a time delay controlled electrical signal, transmit circuitry responsive to the time delay controlled electrical signal for providing to the associated antenna element a transmit signal based on the time delay controlled electrical signal, and receive circuitry responsive to the time delay controlled electrical signal and the signal received by the associated antenna element. A first RF switch selectively couples the time delay controlled electrical signal to the transmit circuit during transmit times, and to the receive circuit during receive times; and a second RF switch couples the associated antenna element to the transmit circuit during transmit times, and to the receive circuit during receive times. The receive circuit further includes analog-to-digital conversion circuitry whose sample timing is controlled so as to provide for time alignment of the received signal relative to the received signals of the other transmit/receive circuits of the phased array. Alternatively, such time alignment is provided pursuant to processing of the sampled receive signals from the transmit/receive circuits of the phased array. <IMAGE></p> |