Systems and methods are disclosed for obtaining distance related wellbore parameters using pulse-echo measurements. For example, the depth of a wellbore may be computed and/or the length of a tubular string positioned in a wellbore may be determined. In an embodiment, a pulsar is deployed into a wellbore along a length of tubular. Once deployed, a fluid pulse is sent form a surface pulse generator and the transmission time is recorded. The downhole pulsar receives the fluid pulse and, in response, returns a second fluid pulse back to the surface. Surface processing circuitry receives the second fluid pulse and records the reception time. The processing circuitry then process the data to determine the total time for travel, thereby determining the length of the downhole pipe or other tubing.