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90-465: The first operational pulse-Doppler radar was in the CIM-10 Bomarc , an American long range supersonic missile powered by ramjet engines, and which was armed with a W40 nuclear weapon to destroy entire formations of attacking enemy aircraft. Pulse-Doppler systems were first widely used on fighter aircraft starting in the 1960s. Earlier radars had used pulse-timing in order to determine range and

180-474: A coherent oscillator with very little noise. Phase noise reduces sub-clutter visibility performance by producing apparent motion on stationary objects. Cavity magnetron and crossed-field amplifier are not appropriate because noise introduced by these devices interfere with detection performance. The only amplification devices suitable for pulse-Doppler are klystron , traveling wave tube , and solid state devices. Pulse-Doppler signal processing introduces

270-407: A phase-shift on the transmit pulse that can produce signal cancellation. Doppler has maximum detrimental effect on moving target indicator systems, which must use reverse phase shift for Doppler compensation in the detector. Doppler weather effects (precipitation) were also found to degrade conventional radar and moving target indicator radar, which can mask aircraft reflections. This phenomenon

360-478: A Bomarc B successfully intercepted a Regulus II cruise missile flying at 100,000 ft (30,000 m), thus achieving the highest interception in the world up to that date. Boeing built 570 Bomarc missiles between 1957 and 1964, 269 CIM-10A, 301 CIM-10B. In September 1958 Air Research & Development Command decided to transfer the Bomarc program from its testing at Cape Canaveral Air Force Station to

450-500: A blind velocity. Ringing artifacts pose a problem with search, detection, and ambiguity resolution in pulse-Doppler radar. CIM-10 Bomarc The Boeing CIM-10 Bomarc ("Boeing Michigan Aeronautical Research Center") ( IM-99 Weapon System prior to September 1962) was a supersonic ramjet powered long-range surface-to-air missile (SAM) used during the Cold War for the air defense of North America. In addition to being

540-636: A course close to the line-of-sight, and the other would fly up to the target's altitude and then tip over and fly horizontally towards the target like a fighter aircraft . As both concepts seemed promising, the Army Air Force was given the task of developing the airplane-like design, while the Army Ordnance Department was given the more ballistic collision-course concept. Official requirements were published in 1945. Official requirements were published in 1945; Bell Laboratories won

630-416: A cruising altitude of 60,000 feet (18,000 m). It was 46.6 ft (14.2 m) long and weighed 15,500 pounds (7,000 kg). Its armament was either a 1,000-pound (450 kg) conventional warhead or a W40 nuclear warhead (7–10 kiloton yield). A liquid-fuel rocket engine boosted the Bomarc to Mach 2, when its Marquardt RJ43-MA-3 ramjet engines, fueled by 80-octane gasoline, would take over for

720-433: A high-resolution spectrum and comparing the measured wavelengths of known spectral lines to wavelengths from laboratory measurements. A positive radial velocity indicates the distance between the objects is or was increasing; a negative radial velocity indicates the distance between the source and observer is or was decreasing. William Huggins ventured in 1868 to estimate the radial velocity of Sirius with respect to

810-457: A much smaller planet with an orbital plane on the line of sight. It has been suggested that planets with high eccentricities calculated by this method may in fact be two-planet systems of circular or near-circular resonant orbit. The radial velocity method to detect exoplanets is based on the detection of variations in the velocity of the central star, due to the changing direction of the gravitational pull from an (unseen) exoplanet as it orbits

900-576: A new facility on Santa Rosa Island , south of Eglin AFB Hurlburt Field on the Gulf of Mexico . To operate the facility and to provide training and operational evaluation in the missile program, Air Defense Command established the 4751st Air Defense Wing (Missile) (4751st ADW) on 15 January 1958. The first launch from Santa Rosa took place on 15 January 1959. In 1955, to support a program which called for 40 squadrons of BOMARC (120 missiles to

990-408: A phenomenon called scalloping. The name is associated with a series of holes that are scooped-out of the detection performance. Scalloping for pulse-Doppler radar involves blind velocities created by the clutter rejection filter. Every volume of space must be scanned using 3 or more different PRF. A two PRF detection scheme will have detection gaps with a pattern of discrete ranges, each of which has

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1080-647: A reality in the mid-1950s, the USAF began to develop a new solid-fueled Bomarc variant, the IM-99B Bomarc ;B. It used a Thiokol XM51 booster, and also had improved Marquardt RJ43-MA-7 (and finally the RJ43-MA-11) ramjets. The first IM-99B was launched in May 1959, but problems with the new propulsion system delayed the first fully successful flight until July 1960, when a supersonic MQM-15A Regulus II drone

1170-403: A record label, Bomarc Records, and a moderately successful Canadian pop group, The Beau Marks . Aircraft of comparable role, configuration, and era Radial velocity The radial velocity or line-of-sight velocity of a target with respect to an observer is the rate of change of the vector displacement between the two points. It is formulated as the vector projection of

1260-408: A squadron for a total of 4,800 missiles), ADC reached a decision on the location of these 40 squadrons and suggested operational dates for each. The sequence was as follows: ... l. McGuire 1/60 2. Suffolk 2/60 3. Otis 3/60 4. Dow 4/60 5. Niagara Falls 1/61 6. Plattsburgh 1/61 7. Kinross 2/61 8. K.I. Sawyer 2/61 9. Langley 2/61 10. Truax 3/61 11. Paine 3/61 12. Portland 3/61 ... At

1350-636: A supersonic manned interceptor aircraft, arguing that the missile program made the Arrow unnecessary. Initially, it was unclear whether the missiles would be equipped with nuclear warheads. By 1960 it became known that the missiles were to have a nuclear payload, and a debate ensued about whether Canada should accept nuclear weapons. Ultimately, the Diefenbaker government decided that the Bomarcs should not be equipped with nuclear warheads. The dispute split

1440-494: A total of 52 sites covering most of the major cities and industrial regions in the US. The United States Army was deploying their own systems at the same time, and the two services fought constantly both in political circles and in the press. Development dragged on, and by the time it was ready for deployment in the late 1950s, the nuclear threat had moved from manned bombers to the intercontinental ballistic missile (ICBM). By this time

1530-404: A vulnerability region in pulse-amplitude time-domain radar . Non-Doppler radar systems cannot be pointed directly at the ground due to excessive false alarms, which overwhelm computers and operators. Sensitivity must be reduced near clutter to avoid overload. This vulnerability begins in the low-elevation region several beam widths above the horizon, and extends downward. This also exists throughout

1620-455: Is 5 km to 50 km. Range and velocity cannot be measured directly using medium PRF, and ambiguity resolution is required to identify true range and speed. Doppler signals are generally above 1 kHz, which is audible, so audio signals from medium-PRF systems can be used for passive target classification. Radar systems require angular measurement. Transponders are not normally associated with pulse-Doppler radar, so sidelobe suppression

1710-572: Is aimed above the horizon to avoid an excessive false alarm rate, which renders systems vulnerable. Aircraft and some missiles exploit this weakness using a technique called flying below the radar to avoid detection ( nap-of-the-earth ). This flying technique is ineffective against pulse-Doppler radar. Pulse-Doppler provides an advantage when attempting to detect missiles and low observability aircraft flying near terrain, sea surface, and weather. Audible Doppler and target size support passive vehicle type classification when identification friend or foe

1800-577: Is also known as clutter rejection. Rejection velocity is usually set just above the prevailing wind speed (10 to 100 mph or 20 to 160 km/h). The velocity threshold is much lower for weather radar . | Doppler frequency × C 2 × transmit frequency | > velocity threshold . {\displaystyle \left\vert {\frac {{\text{Doppler frequency}}\times C}{2\times {\text{transmit frequency}}}}\right\vert >{\text{velocity threshold}}.} In airborne pulse-Doppler radar,

1890-532: Is determined by astrometric observations (for example, a secular change in the annual parallax ). Light from an object with a substantial relative radial velocity at emission will be subject to the Doppler effect , so the frequency of the light decreases for objects that were receding ( redshift ) and increases for objects that were approaching ( blueshift ). The radial velocity of a star or other luminous distant objects can be measured accurately by taking

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1980-410: Is low (above horizon with clear skies). The antenna type is an important consideration for multi-mode radar because undesirable phase shift introduced by the radar antenna can degrade performance measurements for sub-clutter visibility. The signal processing enhancement of pulse-Doppler allows small high-speed objects to be detected in close proximity to large slow moving reflectors. To achieve this,

2070-410: Is not available from a transponder signal . Medium pulse repetition frequency (PRF) reflected microwave signals fall between 1,500 and 15,000 cycle per second, which is audible. This means a helicopter sounds like a helicopter, a jet sounds like a jet, and propeller aircraft sound like propellers. Aircraft with no moving parts produce a tone. The actual size of the target can be calculated using

2160-470: Is required for practical operation. Tracking radar systems use angle error to improve accuracy by producing measurements perpendicular to the radar antenna beam. Angular measurements are averaged over a span of time and combined with radial movement to develop information suitable to predict target position for a short time into the future. The two angle error techniques used with tracking radar are monopulse and conical scan . Pulse-Doppler radar requires

2250-534: Is the angle offset between the antenna position and the aircraft flight trajectory. Surface reflections appear in almost all radar. Ground clutter generally appears in a circular region within a radius of about 25 miles (40 km) near ground-based radar. This distance extends much further in airborne and space radar. Clutter results from radio energy being reflected from the earth surface, buildings, and vegetation. Clutter includes weather in radar intended to detect and report aircraft and spacecraft. Clutter creates

2340-487: Is the phase shift induced by range motion. Rejection speed is selectable on pulse-Doppler aircraft-detection systems so nothing below that speed will be detected. A one degree antenna beam illuminates millions of square feet of terrain at 10 miles (16 km) range, and this produces thousands of detections at or below the horizon if Doppler is not used. Pulse-Doppler radar uses the following signal processing criteria to exclude unwanted signals from slow-moving objects. This

2430-503: Is to reduce the transmitted power while achieving acceptable performance for improved safety of stealthy radar. Pulse-Doppler techniques also find widespread use in meteorological radars , allowing the radar to determine wind speed from the velocity of any precipitation in the air. Pulse-Doppler radar is also the basis of synthetic aperture radar used in radar astronomy , remote sensing and mapping. In air traffic control , they are used for discriminating aircraft from clutter. Besides

2520-502: The Atomic Energy Commission cleaned up the site and covered it with concrete. This was the only major incident involving the weapon system. The site remained in operation for several years following the fire. Since its closure in 1972, the area has remained off limits, primarily due to low levels of plutonium contamination. Between 2002 and 2004, 21,998 cubic yards of contaminated debris and soils were shipped to what

2610-450: The barycentric radial-velocity measure or spectroscopic radial velocity. However, due to relativistic and cosmological effects over the great distances that light typically travels to reach the observer from an astronomical object, this measure cannot be accurately transformed to a geometric radial velocity without additional assumptions about the object and the space between it and the observer. By contrast, astrometric radial velocity

2700-524: The frequency ambiguity resolution process. The range resolution is the minimal range separation between two objects traveling at the same speed before the radar can detect two discrete reflections: range resolution = C PRF × ( number of samples between transmit pulses ) . {\displaystyle {\text{range resolution}}={\frac {C}{{\text{PRF}}\times ({\text{number of samples between transmit pulses}})}}.} In addition to this sampling limit,

2790-481: The norm of the radial velocity, modulo the sign. In astronomy, the point is usually taken to be the observer on Earth, so the radial velocity then denotes the speed with which the object moves away from the Earth (or approaches it, for a negative radial velocity). Given a differentiable vector r ∈ R 3 {\displaystyle \mathbf {r} \in \mathbb {R} ^{3}} defining

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2880-514: The 4751st Air Defense Squadron (Missile) remained at Hurlburt and Santa Rosa Island for training purposes. In 1964, the liquid-fueled Bomarc-A sites and squadrons began to be deactivated. The sites at Dow and Suffolk County closed first. The remainder continued to be operational for several more years while the government started dismantling the air defense missile network. Niagara Falls was the first BOMARC B installation to close, in December 1969;

2970-593: The Air Force to begin a lengthy series of attacks on the Army in the press, a common occurrence at the time known as " policy by press release ". When the Army released its first official information on Ajax to the press, the Air Force responded by leaking information on BOMARC to Aviation Week , and continued to denigrate Nike in the press over the next few years, in one case showing a graphic of Washington being destroyed by nuclear bombs that Ajax failed to stop. Tests of

3060-474: The Army had successfully deployed the much shorter range Nike Hercules that they claimed filled any possible need through the 1960s, in spite of Air Force claims to the contrary. As testing continued, the Air Force reduced its plans to sixteen sites, and then again to eight with an additional two sites in Canada. The first US site was declared operational in 1959, but with only a single working missile. Bringing

3150-473: The Army was beginning to develop its much more powerful successor, Nike Hercules . Hercules was an existential threat to BOMARC, as its much greater range and nuclear warhead filled many of the roles that BOMARC was designed for. A new round of fighting in the press broke out, capped by an article in The New York Times entitled "Air Force Calls Army Nike Unfit To Guard Nation". In October 1957,

3240-558: The Bomarc missiles, which were housed in a constant combat-ready basis in individual launch shelters in remote areas. At the height of the program, there were 14 Bomarc sites located in the US and two in Canada. The liquid-fuel booster of the Bomarc A had several drawbacks. It took two minutes to fuel before launch, which could be a long time in high-speed intercepts, and its hypergolic propellants (hydrazine and nitric acid) were very dangerous to handle, leading to several serious accidents. As soon as high-thrust solid-fuel rockets became

3330-677: The Bomarc was within 10 mi (16 km) of the target, its own Westinghouse AN/DPN-34 radar guided the missile to the interception point. The maximum range of the IM-99A was 250 mi (400 km), and it was fitted with either a conventional high-explosive or a 10 kiloton W-40 nuclear fission warhead. The Bomarc relied on the Semi-Automatic Ground Environment (SAGE), an automated control system used by NORAD for detecting, tracking and intercepting enemy bomber aircraft . SAGE allowed for remote launching of

3420-492: The Diefenbaker Cabinet , and led to the collapse of the government in 1963. The Official Opposition and Liberal Party leader Lester B. Pearson originally was against nuclear missiles, but reversed his personal position and argued in favour of accepting nuclear warheads. He won the 1963 election , largely on the basis of this issue, and his new Liberal government proceeded to accept nuclear-armed Bomarcs, with

3510-585: The IM-99B. However, in March 1960, HQ USAF cut deployment to eight sites in the United States and two in Canada. Within a year of operations, a Bomarc A with a nuclear warhead caught fire at McGuire AFB on 7 June 1960 after its on-board helium tank exploded. While the missile's explosives did not detonate, the heat melted the warhead and released plutonium, which the fire crews spread. The Air Force and

3600-838: The Ordnance contract for a short-range line-of-sight weapon under Project Nike, while a team of players led by Boeing won the contract for a long-range design known as Ground-to-Air Pilotless Aircraft , or GAPA. GAPA moved to the United States Air Force when that branch was formed in 1947. In 1946, the USAAF also started two early research projects into anti-missile systems in Project Thumper (MX-795) and Project Wizard (MX-794). Formally organized in 1946 under USAAF project MX-606, by 1950 Boeing had launched more than 100 test rockets in various configurations, all under

3690-621: The Sun, based on observed redshift of the star's light. In many binary stars , the orbital motion usually causes radial velocity variations of several kilometres per second (km/s). As the spectra of these stars vary due to the Doppler effect, they are called spectroscopic binaries . Radial velocity can be used to estimate the ratio of the masses of the stars, and some orbital elements , such as eccentricity and semimajor axis . The same method has also been used to detect planets around stars, in

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3780-515: The USAF 425th Munitions Maintenance Squadron at Stewart Air Force Base . During operational service, the Bomarcs were maintained on stand-by, on a 24-hour basis, but were never fired, although the squadron test-fired the missiles at Eglin AFB, Florida on annual winter retreats. No. 447 SAM Squadron operating out of RCAF Station La Macaza, Quebec , was activated on 15 September 1962 although warheads were not delivered until late 1963. The squadron followed

3870-507: The USAF discontinued the use of aircraft-like type designators for missiles, and the XF-99A and YF-99A became XIM-99A and YIM-99A, respectively. Originally the USAF had allocated the designation IM-69, but this was changed (possibly at Boeing's request to keep number 99) to IM-99 in October 1955. By this time, Ajax was widely deployed around the United States and some overseas locations, and

3960-574: The United States Air Force, and later for the Lockheed YF-12 . The US's first pulse-Doppler radar, the system had look-down/shoot-down capability and could track one target at a time. It became possible to use pulse-Doppler radar on aircraft after digital computers were incorporated in the design. Pulse-Doppler provided look-down/shoot-down capability to support air-to-air missile systems in most modern military aircraft by

4050-408: The United States with 120 missiles each but as defense budgets decreased during the 1950s the number of sites dropped substantially. Ongoing development and reliability problems didn't help, nor did Congressional debate over the missile's usefulness and necessity. In June 1959, the Air Force authorized 16 Bomarc sites with 56 missiles each; the initial five would get the IM-99A with the remainder getting

4140-544: The XF-99 test vehicles began in September 1952 and continued through early 1955. The XF-99 tested only the liquid-fueled booster rocket, which would accelerate the missile to ramjet ignition speed. In February 1955, tests of the XF-99A propulsion test vehicles began. These included live ramjets, but still had no guidance system or warhead. The designation YF-99A had been reserved for the operational test vehicles. In August 1955,

4230-404: The above conventional surveillance applications, pulse-Doppler radar has been successfully applied in healthcare, such as fall risk assessment and fall detection, for nursing or clinical purposes. The earliest radar systems failed to operate as expected. The reason was traced to Doppler effects that degrade performance of systems not designed to account for moving objects. Fast-moving objects cause

4320-541: The accident, the McGuire complex has never been sold or converted to other uses and remains in Air Force ownership, making it the most intact site of the eight in the US. It has been nominated to the National Register of Historic Sites. Although a number of IM-99/CIM-10 Bomarcs have been placed on public display, because of concerns about the possible environmental hazards of the thoriated magnesium structure of

4410-620: The airframe several have been removed from public view. Russ Sneddon, director of the Air Force Armament Museum , Eglin Air Force Base, Florida provided information about missing CIM-10 exhibit airframe serial 59–2016, one of the museum's original artifacts from its founding in 1975 and donated by the 4751st Air Defense Squadron at Hurlburt Field , Eglin Auxiliary Field 9, Eglin AFB. As of December 2006,

4500-510: The angle of the antenna (or similar means) to determine the bearing. However, this only worked when the radar antenna was not pointed down; in that case the reflection off the ground overwhelmed any returns from other objects. As the ground moves at the same speed but opposite direction of the aircraft, Doppler techniques allow the ground return to be filtered out, revealing aircraft and vehicles. This gives pulse-Doppler radars " look-down/shoot-down " capability. A secondary advantage in military radar

4590-461: The audible signal. Ambiguity processing is required when target range is above the red line in the graphic, which increases scan time. Scan time is a critical factor for some systems because vehicles moving at or above the speed of sound can travel one mile (1.6 km) every few seconds, like the Exocet , Harpoon , Kitchen , and air-to-air missiles . The maximum time to scan the entire volume of

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4680-536: The derivative of the right-hand-side by the chain rule using ( 1 ) the expression becomes By reciprocity, ⟨ v , r ⟩ = ⟨ r , v ⟩ {\displaystyle \langle \mathbf {v} ,\mathbf {r} \rangle =\langle \mathbf {r} ,\mathbf {v} \rangle } . Defining the unit relative position vector r ^ = r / r {\displaystyle {\hat {r}}=\mathbf {r} /{r}} (or LOS direction),

4770-505: The designator XSAM-A-1 GAPA. The tests were very promising, and Boeing received a USAF contract in 1949 to develop a production design under project MX-1599. The MX-1599 missile was to be a ramjet-powered, nuclear-armed long-range surface-to-air missile to defend the Continental United States from high-flying bombers. The Michigan Aerospace Research Center (MARC) was added to the project soon afterward, and this gave

4860-924: The duration of the transmitted pulse could mean that returns from two targets will be received simultaneously from different parts of the pulse. The velocity resolution is the minimal radial velocity difference between two objects traveling at the same range before the radar can detect two discrete reflections: velocity resolution = C × PRF 2 × transmit frequency × filter size in transmit pulses . {\displaystyle {\text{velocity resolution}}={\frac {C\times {\text{PRF}}}{2\times {\text{transmit frequency}}\times {\text{filter size in transmit pulses}}}}.} Pulse-Doppler radar has special requirements that must be satisfied to achieve acceptable performance. Pulse-Doppler typically uses medium pulse repetition frequency (PRF) from about 3 kHz to 30 kHz. The range between transmit pulses

4950-533: The emerging jet-powered designs. Like the Germans and British before them, they concluded the only successful defence would be to use guided weapons. As early as 1944 the United States Army started exploring anti-aircraft missiles, examining a variety of concepts. At the time, two basic concepts appeared possible; one would use a short-range rocket that flew directly at the target from below following

5040-558: The end of 1958, ADC plans called for construction of the following BOMARC bases in the following order: l. McGuire 2. Suffolk 3. Otis 4. Dow 5. Langley 6. Truax 7. Kinross 8. Duluth 9. Ethan Allen 10. Niagara Falls 11. Paine 12. Adair 13. Travis 14. Vandenberg 15. San Diego 16. Malmstrom 17. Grand Forks 18. Minot 19. Youngstown 20. Seymour-Johnson 21. Bunker Hill 22. Sioux Falls 23. Charleston 24. McConnell 25. Holloman 26. McCoy 27. Amarillo 28. Barksdale 29. Williams . The first USAF operational Bomarc squadron

5130-465: The first YIM-99A production-representative prototype flew with full guidance, and succeeded to pass the target within destructive range. In late 1957, Boeing received the production contract for the IM-99A Bomarc A, and in September 1959, the first IM-99A squadron became operational. The IM-99A had an operational radius of 200 miles (320 km) and was designed to fly at Mach  2.5–2.8 at

5220-407: The first being deployed on 31 December 1963. When the nuclear warheads were deployed, Pearson's wife, Maryon, resigned her honorary membership in the anti-nuclear weapons group, Voice of Women. Canadian operational deployment of the Bomarc involved the formation of two specialized Surface/Air Missile squadrons. The first to begin operations was No. 446 SAM Squadron at RCAF Station North Bay , which

5310-420: The first operational long-range SAM and the first operational pulse doppler aviation radar, it was the only SAM deployed by the United States Air Force . Stored horizontally in a launcher shelter with a movable roof, the missile was erected, fired vertically using rocket boosters to high altitude, and then tipped over into a horizontal Mach 2.5 cruise powered by ramjet engines. This lofted trajectory allowed

5400-418: The inner product is either +1 or -1, for parallel and antiparallel vectors , respectively. A singularity exists for coincident observer target, i.e., r = 0 {\displaystyle r=0} ; in this case, range rate is undefined. In astronomy, radial velocity is often measured to the first order of approximation by Doppler spectroscopy . The quantity obtained by this method may be called

5490-518: The instantaneous relative position of a target with respect to an observer. Let the instantaneous relative velocity of the target with respect to the observer be The magnitude of the position vector r {\displaystyle \mathbf {r} } is defined as in terms of the inner product The quantity range rate is the time derivative of the magnitude ( norm ) of r {\displaystyle \mathbf {r} } , expressed as Substituting ( 2 ) into ( 3 ) Evaluating

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5580-523: The launch of an unarmed missile at Eglin. In September 1959 the squadron assembled at their permanent station, the Bomarc site near McGuire AFB, and trained for operational readiness. The first Bomarc-A were used at McGuire on 19 September 1959 with Kincheloe AFB getting the first operational IM-99Bs. While several of the squadrons replicated earlier fighter interceptor unit numbers, they were all new organizations with no previous historical counterpart. ADC's initial plans called for some 52 Bomarc sites around

5670-573: The launch order, the shelter's roof would slide open, and the missile raised to the vertical. After the missile was supplied with fuel for the booster rocket, it would be launched by the Aerojet General LR59-AJ-13 booster. After sufficient speed was reached, the Marquardt RJ43-MA-3 ramjets would ignite and propel the missile to its cruise speed of Mach 2.8 at an altitude of 66,000 ft (20,000 m). When

5760-448: The mid 1970s. Pulse-Doppler systems measure the range to objects by measuring the elapsed time between sending a pulse of radio energy and receiving a reflection of the object. Radio waves travel at the speed of light , so the distance to the object is the elapsed time multiplied by the speed of light, divided by two – there and back. Pulse-Doppler radar is based on the Doppler effect , where movement in range produces frequency shift on

5850-476: The missile to operate at a maximum range as great as 430 mi (690 km). Controlled from the ground for most of its flight, when it reached the target area it was commanded to begin a dive, activating an onboard active radar homing seeker for terminal guidance . A radar proximity fuse detonated the warhead, either a large conventional explosive or the W40 nuclear warhead . The Air Force originally planned for

5940-487: The new missile its name Bomarc (for Boeing and MARC). In 1951, the USAF decided to emphasize its point of view that missiles were nothing else than pilotless aircraft by assigning aircraft designators to its missile projects, and anti-aircraft missiles received F-for-Fighter designations. The Bomarc became the F-99 . By this time, the Army's Nike project was progressing well and would enter operational service in 1953. This led

6030-568: The others remained on alert through 1972. In April 1972, the last Bomarc B in U.S. Air Force service was retired at McGuire and the 46th ADMS inactivated and the base was deactivated. In the era of the intercontinental ballistic missiles the Bomarc, designed to intercept relatively slow manned bombers, had become a useless asset. The remaining Bomarc missiles were used by all armed services as high-speed target drones for tests of other air-defense missiles. The Bomarc A and Bomarc B targets were designated as CQM-10A and CQM-10B, respectively. Following

6120-482: The phase of each transmitted pulse for comparison to returned echoes. Early examples of military systems includes the AN/SPG-51 B developed during the 1950s specifically for the purpose of operating in hurricane conditions with no performance degradation. The Hughes AN/ASG-18 Fire Control System was a prototype airborne radar/combination system for the planned North American XF-108 Rapier interceptor aircraft for

6210-499: The radar to separate the reflections from multiple objects located in the same volume of space by separating the objects using a spread spectrum to segregate different signals: v = target speed = λ Δ Θ 4 π Δ t , {\displaystyle v={\text{target speed}}={\frac {\lambda \Delta \Theta }{4\pi \Delta t}},} where Δ Θ {\displaystyle \Delta \Theta }

6300-485: The range rate is simply expressed as i.e., the projection of the relative velocity vector onto the LOS direction. Further defining the velocity direction v ^ = v / v {\displaystyle {\hat {v}}=\mathbf {v} /{v}} , with the relative speed v = ‖ v ‖ {\displaystyle v=\|\mathbf {v} \|} , we have: where

6390-650: The remainder of the flight. This was the same model of engine used to power the Lockheed X-7 , the Lockheed AQM-60 Kingfisher drone used to test air defenses, and the Lockheed D-21 launched from the back of an M-21 , although the Bomarc and Kingfisher engines used different materials due to the longer duration of their flights. The operational IM-99A missiles were based horizontally in semi-hardened shelters, nicknamed "coffins". After

6480-541: The rest of the missiles into service took years, by which time the system was obsolete. Deactivations began in 1969 and by 1972 all Bomarc sites had been shut down. A small number were used as target drones, and only a few remain on display today. During World War II , the US Army Air Force (USAAF) concluded that existing anti-aircraft guns , only marginally effective against existing generations of propeller-driven aircraft, would not be effective at all against

6570-501: The return signals from at least 3 different PRFs can be processed out to the maximum anticipated detection range. This is known as dwell time . Antenna motion for pulse-Doppler must be as slow as radar using MTI . Search radar that include pulse-Doppler are usually dual mode because best overall performance is achieved when pulse-Doppler is used for areas with high false alarm rates (horizon or below and weather), while conventional radar will scan faster in free-space where false alarm rate

6660-957: The returned signal has a phase difference, or phase shift , from pulse to pulse. This causes the reflector to produce Doppler modulation on the reflected signal. Pulse-Doppler radars exploit this phenomenon to improve performance. The amplitude of the successively returning pulse from the same scanned volume is I = I 0 sin ⁡ ( 4 π ( x 0 + v Δ t ) λ ) = I 0 sin ⁡ ( Θ 0 + Δ Θ ) , {\displaystyle I=I_{0}\sin \left({\frac {4\pi (x_{0}+v\Delta t)}{\lambda }}\right)=I_{0}\sin(\Theta _{0}+\Delta \Theta ),} where So Δ Θ = 4 π v Δ t λ . {\displaystyle \Delta \Theta ={\frac {4\pi v\Delta t}{\lambda }}.} This allows

6750-568: The same operational procedures as No. 446, its sister squadron. With the passage of time the operational capability of the 1950s-era Bomarc system no longer met modern requirements; the Department of National Defence deemed that the Bomarc missile defense was no longer a viable system, and ordered both squadrons to be stood down in 1972. The bunkers and ancillary facilities remain at both former sites. Download coordinates as: Locations under construction but not activated. Each site

6840-435: The signal reflected from the target. Doppler frequency = 2 × transmit frequency × radial velocity C . {\displaystyle {\text{Doppler frequency}}={\frac {2\times {\text{transmit frequency}}\times {\text{radial velocity}}}{C}}.} Radial velocity is essential for pulse-Doppler radar operation. As the reflector moves between each transmit pulse,

6930-480: The sky must be on the order of a dozen seconds or less for systems operating in that environment. Pulse-Doppler radar by itself can be too slow to cover the entire volume of space above the horizon unless fan beam is used. This approach is used with the AN/SPS 49(V)5 Very Long Range Air Surveillance Radar, which sacrifices elevation measurement to gain speed. Pulse-Doppler antenna motion must be slow enough so that all

7020-420: The star. When the star moves towards us, its spectrum is blueshifted, while it is redshifted when it moves away from us. By regularly looking at the spectrum of a star—and so, measuring its velocity—it can be determined if it moves periodically due to the influence of an exoplanet companion. From the instrumental perspective, velocities are measured relative to the telescope's motion. So an important first step of

7110-537: The suspect missile was stored in a secure compound behind the Armaments Museum. In December 2010, the airframe was still on premises, but partly dismantled. The Bomarc Missile Program was highly controversial in Canada. The Progressive Conservative government of Prime Minister John Diefenbaker initially agreed to deploy the missiles, and shortly thereafter controversially scrapped the Avro Arrow ,

7200-399: The target-observer relative velocity onto the relative direction or line-of-sight (LOS) connecting the two points. The radial speed or range rate is the temporal rate of the distance or range between the two points. It is a signed scalar quantity , formulated as the scalar projection of the relative velocity vector onto the LOS direction. Equivalently, radial speed equals

7290-445: The transmitter must be coherent and should produce low phase noise during the detection interval, and the receiver must have large instantaneous dynamic range . Pulse-Doppler signal processing also includes ambiguity resolution to identify true range and velocity. The received signals from multiple PRF are compared to determine true range using the range ambiguity resolution process. The received signals are also compared using

7380-598: The velocity threshold is offset by the speed of the aircraft relative to the ground. | Doppler frequency × C 2 × transmit frequency − ground speed × cos ⁡ Θ | > velocity threshold , {\displaystyle \left\vert {\frac {{\text{Doppler frequency}}\times C}{2\times {\text{transmit frequency}}}}-{\text{ground speed}}\times \cos \Theta \right\vert >{\text{velocity threshold}},} where Θ {\displaystyle \Theta }

7470-508: The volume of moving air associated with weather phenomenon. Pulse-Doppler radar corrects this as follows. Clutter rejection capability of about 60 dB is needed for look-down/shoot-down capability, and pulse-Doppler is the only strategy that can satisfy this requirement. This eliminates vulnerabilities associated with the low-elevation and below-horizon environment. Pulse compression and moving target indicator (MTI) provide up to 25 dB sub-clutter visibility. An MTI antenna beam

7560-399: The way that the movement's measurement determines the planet's orbital period, while the resulting radial-velocity amplitude allows the calculation of the lower bound on a planet's mass using the binary mass function . Radial velocity methods alone may only reveal a lower bound, since a large planet orbiting at a very high angle to the line of sight will perturb its star radially as much as

7650-510: Was adapted for use with weather radar in the 1950s after declassification of some World War II systems. Pulse-Doppler radar was developed during World War II to overcome limitations by increasing pulse repetition frequency . This required the development of the klystron , the traveling wave tube , and solid state devices. Early pulse-dopplers were incompatible with other high power microwave amplification devices that are not coherent , but more sophisticated techniques were developed that record

7740-629: Was intercepted. Because the new booster required less space in the missile, more ramjet fuel could be carried, thus increasing the range to 430 mi (700 km). The terminal homing system was also improved, using the world's first pulse Doppler search radar , the Westinghouse AN/DPN-53. All Bomarc Bs were equipped with the W-40 nuclear warhead. In June 1961, the first IM-99B squadron became operational, and Bomarc B quickly replaced most Bomarc A missiles. On 23 March 1961,

7830-454: Was programmed for 28 IM-99B missiles: Reference for BOMARC units and locations: Below is a list of museums or sites which have a Bomarc missile on display: The Bomarc missile captured the imagination of the American and Canadian popular music industry, giving rise to a pop music group, the Bomarcs (composed mainly of servicemen stationed on a Florida radar site that tracked Bomarcs),

7920-523: Was the 46th Air Defense Missile Squadron (ADMS), organized on 1 January 1959 and activated on 25 March. The 46th ADMS was assigned to the New York Air Defense Sector at McGuire Air Force Base , New Jersey. The training program, under the 4751st Air Defense Wing used technicians acting as instructors and was established for a four-month duration. Training included missile maintenance; SAGE operations and launch procedures, including

8010-409: Was the command and control center for both squadrons. With construction of the compound and related facilities completed in 1961, the squadron received its Bomarcs in 1961, without nuclear warheads. The squadron became fully operational from 31 December 1963, when the nuclear warheads arrived, until disbanding on 31 March 1972. All the warheads were stored separately and under control of Detachment 1 of

8100-620: Was then known as Envirocare , located in Utah. In 1962, the US Air Force started using modified A-models as drones; following the October 1962 tri-service redesignation of aircraft and weapons systems they became CQM-10As. Otherwise the air defense missile squadrons maintained alert while making regular trips to Santa Rosa Island for training and firing practice. After the inactivation of the 4751st ADW(M) on 1 July 1962 and transfer of Hurlburt to Tactical Air Command for air commando operations

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