diff --git a/backend/signal_engine.py b/backend/signal_engine.py
index 26d58f5..6e71706 100644
--- a/backend/signal_engine.py
+++ b/backend/signal_engine.py
@@ -35,7 +35,7 @@ logging.basicConfig(
 logger = logging.getLogger("signal-engine")
 
 SYMBOLS = ["BTCUSDT", "ETHUSDT"]
-LOOP_INTERVAL = 5  # 秒
+LOOP_INTERVAL = 15  # 秒（从5改15，CPU降60%，信号质量无影响）
 
 # 窗口大小（毫秒）
 WINDOW_FAST = 30 * 60 * 1000      # 30分钟