Going to need more than a screenshot of the waterfall. A recording would really help, but other details would also help. What kind of SDR? What kind of antenna? What kind of LNA? What general area? When you listened to the signals, what did it sound like? What receiver mode did you sue when listening?
The more detail you can provide, the more likely you are to get a meaningful response. But seriously, without a recording, every response will be a guess.
T!