Distributed antenna system equipment

Abstract

To provide a distributed antenna system device that can eliminate interference caused by upstream signals leaking into downstream signals and control TDD timing more accurately.SOLUTION: A distributed antenna system device includes: a circulator 101 which outputs a downlink signal from a higher-level device to a downlink signal processing unit, and controls so as to output an uplink signal from an uplink signal processing unit to the higher-level device; an uplink signal leakage cancellation unit 111 that inputs the downlink signal from the circulator 101 and the uplink signal from the uplink signal processing unit, cancels a sneak path of the uplink signal contained in the downlink signal, and outputs the cancelled signal; and a TDD detection unit 107 that detects the timing of time division duplexing on the basis of the cancelled signal.SELECTED DRAWING: Figure 1

Claims

1. A distributed antenna system device used in time-division duplex wireless communication, A downlink signal processing unit that performs signal processing for downlink signals, An up-signal processing unit that processes the up-signal, A circulator that controls the output of a downstream signal from a higher-level device to the downstream signal processing unit and the output of an upstream signal from the upstream signal processing unit to the higher-level device, A cancellation unit receives a downlink signal from the circulator and an uplink signal from the uplink signal processing unit, cancels out the uplink signal included in the downlink signal from the circulator, and outputs a cancelled signal. A distributed antenna system device characterized by having a detection unit that detects the timing of time-division duplexing based on the aforementioned canceled signal.

2. The distributed antenna system device according to claim 1, characterized in that the downstream signal processing unit performs signal processing on the downstream signal from the circulator that has been canceled via the cancellation unit.

3. The aforementioned cancellation unit is A first amplitude conversion unit that converts the amplitude of the downstream signal from the circulator that is input, A delay adjustment unit that adjusts the delay of the incoming signal from a lower-level device based on a delay adjustment value, A second amplitude conversion unit that converts the amplitude of the signal delayed by the aforementioned delay adjustment unit, A gain adjustment unit generates a replica signal by adjusting the gain of the signal amplitude-converted by the second amplitude conversion unit based on a gain adjustment value, A canceller that cancels out the upstream signal interference included in the amplitude-converted signal of the signal converted by the first amplitude conversion unit using the replica signal and outputs the canceled signal, The distributed antenna system device according to claim 1 or 2, further comprising: a delay / gain calculation unit that receives the downlink signal and the signal delayed by the delay adjustment unit, calculates the amount of delay of the uplink signal from the lower-level device with respect to the leakage of the uplink signal included in the downlink signal and outputs the delay adjustment value, and calculates the gain of the signal amplitude-converted by the second amplitude conversion unit and outputs the gain adjustment value.

4. The aforementioned delay / gain calculation unit is: A pseudo-replica signal generation unit receives the delayed uplink signal adjusted by the aforementioned delay adjustment unit, generates a pseudo-replica signal, and outputs a prompt signal, an early signal, and a late signal with altered timing. A correlation calculation unit performs correlation calculations between the downlink signal and the prompt signal, the downlink signal and the early signal, and the downlink signal and the late signal, and outputs the respective correlation calculation values. A gain adjustment value calculation unit that calculates a gain adjustment value from the correlation calculation value between the downlink signal and the prompt signal, A discriminator that calculates the difference in timing between the delay-adjusted uplink signal and the feedback included in the downlink signal from the correlation calculation value between the downlink signal and the early signal and the correlation calculation value between the downlink signal and the late signal, The distributed antenna system device according to claim 3, further comprising an accumulator that outputs a delay adjustment value by adding the difference in timings.

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