AZUSA AZUSA refers to a ground - based radar tracking system installed at Cape Canaveral , Florida and the NASA Kennedy Space Center . AZUSA dated back to the early 1950s and was named after the southern California town ( Azusa , California ) where the system was devised . Radar interferometry . Radio interferometry has the advantage of yielding very accurate tracking angles when the target cooperates by emitting a radio signal . The angular precision of interferometry led to the development of the Azusa tracking system as part of the Army Air Corps NUL - 774 Project , forerunner of the Atlas ICBM program , at the Vultee Field Division of Consolidated Vultee Aircraft Corporation in Downey , California . Two of the basic patents ( 2 , 972 , 047 and 3 , 025 , 520 ) in the field of interferometer tracking are shared by James Crooks , Jr . , Robert C . Weaver , and Robert V . Werner , all members of the Azusa design team . By the spring of 1948 , the Azusa team had built an interferometer operating at 148 . 58 MHz . In a strange circle of history , the U . S . Naval Research Laboratory ( NRL ) was working on underwater sound interferometers at the time Convair was developing Azusa . Since the two groups were in close contact , there was considerable interchange of ideas . * The circle was completed in the early 1950s when the Navy picked up the Azusa interferometer work for its Viking project at White Sands , New Mexico . The Navy wanted to explore the possibility of converting the Viking or some derivative of it into a guided missile and it needed an accurate guidance system . In an early report from this program , NRL ' s J . Carl Seddon explained how the Viking would determine its position : " The Missile will detect its position relative to the hyperbolic guidance path by phase comparison of modulation waveforms derived from signals received from two pairs of stations . " In this scheme , the missile would guide itself using onboard electronics and navigational signals received from the ground . This seems a far cry from Minitrack and satellite tracking , but phase comparison , the essence of Minitrack , is there . Within a year , NRL reports from the Viking program were diagramming ground - based , tracking interferometers , which relieved the Viking of the burden of signal - processing equipment by computing the missile ' s position from the ground . Two precursors of Minitrack are evident in the interferometer arrangement . First , only a tiny radio beacon needs to be carried on the Viking itself . This was to be an important feature of the Vanguard " Minitrack , " in which the prefix ' Mini " applies to the minimum - weight satellite transmitter . The second precursor is the " Lff arrangement of the interferometer antennas which persisted in some early designs of Minitrack , although the final deployed version extended the bars of the " L " to make a cross . USAF Atlantic Missile Range , Cape Canaveral , Florida . While the fact that some scientific satellites " achieve orbit " is enough , vehicles carrying men or payloads that must be placed in precise positions , such as geosynchronous satellites , require improved trajectory position and velocity measurement systems . In the early 1960s , the mainstay for obtaining this data at Canaveral was Convair ' s Azusa Mark I , a c - w cross baseline interferometer operating in the C band , requiring a transponder in the missile . Output data were digitized for use in the IBM 709 computer and measured parameters consist of range , coherent or fine range , and two direction cosines . The Azusa II , intended to replace Azusa I , was installed in 1961 . It is nearly identical to the Mark I except that its circuit design was refined and cosine rate was added which provides better direction cosine information . Both Azusas have identical limitations : they will not track cross - polarized signals ; missile antenna nulls deeper than 10 dB cause noisy data , ambiguities and , in severe cases , loss of data . Use in Apollo Program . The AZUSA tracking radar was used to monitor initial phases of launch for the Saturn S - II by telemetry with transponder frequency of 5 , 060 MHz ( receiver ) and 5 , 000 MHz ( transmitter ) with 2 . 5 W of power . Tribute to Robert Weaver . Robert Christian Weaver Sr . , co - inventor of the AZUSA radar , had a post - World War II career in the aerospace industry that influenced the future of guided missiles and other space vehicles . In the early 1950s , Weaver and a colleague invented the AZUSA continuous wave tracking system , implemented at the Air Force Missile Test Center , Cape Canaveral . This system was designed to measure the trajectory of missiles , and was instrumental in pioneering military missile tests and the Project Mercury manned space program . Mr . Weaver began his civilian career with what was then Consolidated Vultee Aircraft in 1946 . " After the war he had a choice of engineering jobs — one in Los Angeles , the other in San Diego with Consolidated , " his son said . Mr . Weaver , whose engineering career with the Convair Division of General Dynamics spanned 35 years , died in September 2003 at the White Sands of La Jolla retirement community . He was 87 . He died of natural causes , said his son , Robert Weaver Jr . The technology that Mr . Weaver and his colleague , Jim Crooks , devised flourished during the Cold War . It was applied to the Navy ' s Polaris program and the Air Force ' s Thor , Atlas and Titan programs . It also was used by NASA in the Saturn IV ( Apollo ) program . One of the advantages of the Azusa system over its predecessors was that it required fewer radar sites and operating crews . The increased emphasis on ballistic missiles and efforts to improve their accuracy spurred the development of the Azusa system and Mistram , a competing technology developed by GE in the early 1960s . Choosing the San Diego assignment , Mr . Weaver made his home in La Jolla . He was familiar with the area from a 1933 visit to La Jolla Shores , where he had camped out with friends in cow fields , his son said . Mr . Weaver , a Fresno native , graduated from the University of California Berkeley in 1938 with a bachelor ' s degree in electrical engineering . He joined the Army Air Corps in 1940 , rising to major during World War II . He was responsible for radio and radar equipment in the China - Burma - India theater . Later , with Convair , Mr . Weaver ' s assignments took him to Cape Canaveral and several other test sites . His specialty became designing radar , guidance and tracking systems for guided missiles and space vehicles . Computers , electronic gadgets and photography occupied much of his leisure time . He also enjoyed sports cars , as well as " the green flashes of the La Jolla sunsets and the breathtaking beauty of Yosemite Valley , " his son said .