A signal sending method, comprising: Sending, by a first transmit site, a first discovery reference signal, DsRS 1 to first user equipment, UE by using a first transmit power and a first transmit period, wherein the first discovery reference signal is used by the first UE for signal quality measurement; sending, by the first transmit site, a second discovery reference signal, DsRS 2 to second user equipment, UE by using a second transmit power and a second transmit period, wherein the second discovery reference signal is used by the second UE for signal quality measurement; and receiving, by the first transmit site, a first signal measurement result of the first UE for the first discovery reference signal, and receiving a second signal measurement result of the second UE for the second discovery reference signal; determine, by the first transmit site, whether to switch an operation mode according to the first signal measurement result and the second signal measurement result; wherein the first UE is an earlier-version UE, the second UE is a new-version UE, the first transmit site is in a sleeping mode; wherein the DsRS 1 comprises one or more of the following: a primary synchronization signal, PSS, a secondary synchronization signal, SSS, and a cell-specific reference signal, CRS, and the DsRS 2 comprises one or more of the following: a PSS, an SSS, and a CRS; or, the DsRS 1 comprises one or more of the following: a primary synchronization signal PSS, a secondary synchronization signal SSS, and a channel state information-reference signal CSI-RS, and the DsRS 2 comprises one or more of the following: a PSS, an SSS, and a CSI-RS. Sending, by a first transmit site, a first discovery reference signal, DsRS 1 to first user equipment, UE by using a first transmit power and a first transmit period, wherein the first discovery reference signal is used by the first UE for signal quality measurement; sending, by the first transmit site, a second discovery reference signal, DsRS 2 to second user equipment, UE by using a second transmit power and a second transmit period, wherein the second discovery reference signal is used by the second UE for signal quality measurement; and receiving, by the first transmit site, a first signal measurement result of the first UE for the first discovery reference signal, and receiving a second signal measurement result of the second UE for the second discovery reference signal; determine, by the first transmit site, whether to switch an operation mode according to the first signal measurement result and the second signal measurement result; wherein the first UE is an earlier-version UE, the second UE is a new-version UE, the first transmit site is in a sleeping mode; wherein the DsRS 1 comprises one or more of the following: a primary synchronization signal, PSS, a secondary synchronization signal, SSS, and a cell-specific reference signal, CRS, and the DsRS 2 comprises one or more of the following: a PSS, an SSS, and a CRS; or, the DsRS 1 comprises one or more of the following: a primary synchronization signal PSS, a secondary synchronization signal SSS, and a channel state information-reference signal CSI-RS, and the DsRS 2 comprises one or more of the following: a PSS, an SSS, and a CSI-RS. a primary synchronization signal, PSS, a secondary synchronization signal, SSS, and a cell-specific reference signal, CRS, and the DsRS 2 comprises one or more of the following: a PSS, an SSS, and a CRS; or, a PSS, an SSS, and a CRS; the DsRS 1 comprises one or more of the following: a primary synchronization signal PSS, a secondary synchronization signal SSS, and a channel state information-reference signal CSI-RS, and a primary synchronization signal PSS, a secondary synchronization signal SSS, and a channel state information-reference signal CSI-RS, and the DsRS 2 comprises one or more of the following: a PSS, an SSS, and a CSI-RS. a PSS, an SSS, and a CSI-RS.