title: Denel Rooivalk

text: On 17 May 2007, Denel group CEO Shaun Liebenberg announced a decision to cease further development and funding for the Rooivalk as an export product following its failure to win the Turkish attack helicopter tender against the Agusta A129 Mangusta.


title: Denel Rooivalk

text: During November 2007, Defence Minister Mosiuoa Lekota announced in Parliament, that the SAAF was to invest R962 million (about US$137 million in 2007 exchange rates) in the helicopter over three years to 2010/2011, in order to bring it up to full operational status. The helicopter was expected to be deployed on peace-keeping duties as soon as initial operating capability is achieved.


title: Denel Rooivalk

text: On 1 April 2011, the SAAF received the first five of eleven (one of the twelve aircraft originally delivered to the SAAF was written off after an accident) Block 1F upgraded Rooivalk. The upgrade involves improved targeting systems and other avionics which enable the helicopter to use guided missiles for the first time. The Mokopa ATGM was qualified as part of the upgrade process. Gearbox components were improved and cooling problems with the F2 20 mm cannon were also addressed. The ninth and tenth Rooivalk attack helicopters were delivered in September 2012 following their upgrade to the Block 1F initial operating standard. The eleventh and final Rooivalk was delivered on 13 March 2013.


title: Denel Rooivalk

text: Three Rooivalk attack helicopters have been deployed with the United Nations Force Intervention Brigade to support the United Nations Organization Stabilization Mission in the Democratic Republic of the Congo in 2013.


title: Denel Rooivalk

text: On 4 November 2013, two Rooivalks with the United Nations Force Intervention Brigade fired "FZ 90 70mm FFAR" rockets on M23 positions near Chanzu in the Democratic Republic of the Congo.


title: Denel Rooivalk

text: The first prototype Rooivalk XDM, SAAF serial 683, is on static display at the South African Air Force Museum, Swartkop Air Force Base, Pretoria.


title: Superheterodyne receiver

text: A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency. It was long believed to have been invented by US engineer Edwin Armstrong, but after some controversy the earliest patent for the invention is now credited to French radio engineer and radio manufacturer Lucien Lévy. Virtually all modern radio receivers use the superheterodyne principle; except those software-defined radios using "direct sampling".


title: Superheterodyne receiver

text: Early Morse code radio broadcasts were produced using an alternator connected to a spark gap. The output signal was at a carrier frequency defined by the physical construction of the gap, modulated by the alternating current signal from the alternator. Since the output frequency of the alternator was generally in the audible range, this produces an audible amplitude modulated (AM) signal. Simple radio detectors filtered out the high-frequency carrier, leaving the modulation, which was passed on to the user's headphones as an audible signal of dots and dashes.


title: Superheterodyne receiver

text: In 1904, Ernst Alexanderson introduced the Alexanderson alternator, a device that directly produced radio frequency output with higher power and much higher efficiency than the older spark gap systems. In contrast to the spark gap, however, the output from the alternator was a pure carrier wave at a selected frequency. When detected on existing receivers, the dots and dashes would normally be inaudible, or "supersonic". Due to the filtering effects of the receiver, these signals generally produced a click or thump, which were audible but made determining dot or dash difficult.


title: Superheterodyne receiver

text: In 1905, Canadian inventor Reginald Fessenden came up with the idea of using two Alexanderson alternators operating at closely spaced frequencies to broadcast two signals, instead of one. The receiver would then receive both signals, and as part of the detection process, only the beat frequency would exit the receiver. By selecting two carriers close enough that the beat frequency was audible, the resulting Morse code could once again be easily heard even in simple receivers. For instance, if the two alternators operated at frequencies 3 kHz apart, the output in the headphones would be dots or dashes of 3 kHz tone, making them easily audible.


title: Superheterodyne receiver

text: Fessenden coined the term "heterodyne", meaning "generated by a difference" (in frequency), to describe this system. The word is derived from the Greek roots "hetero-" "different", and "-dyne" "power".


title: Superheterodyne receiver

text: Morse code was widely used in the early days of radio because it was both easy to produce and easy to receive. In contrast to voice broadcasts, the output of the amplifier didn't have to closely match the modulation of the original signal. As a result, any number of simple amplification systems could be used. One method used an interesting side-effect of early triode amplifier tubes. If both the plate (anode) and grid were connected to resonant circuits tuned to the same frequency and the stage gain was much higher than unity, stray capacitive coupling between the grid and the plate would cause the amplifier to go into oscillation.


title: Superheterodyne receiver

text: In 1913, Edwin Howard Armstrong described a receiver system that used this effect to produce audible Morse code output using a single triode. The output of the amplifier taken at the anode was connected back to the input through a "tickler", causing feedback that drove input signals well beyond unity. This caused the output to oscillate at a chosen frequency with great amplification. When the original signal cut off at the end of the dot or dash, the oscillation decayed and the sound disappeared after a short delay.


title: Superheterodyne receiver

text: Armstrong referred to this concept as a regenerative receiver, and it immediately became one of the most widely used systems of its era. Many radio systems of the 1920s were based on the regenerative principle, and it continued to be used in specialized roles into the 1940s, for instance in the IFF Mark II.


title: Superheterodyne receiver

text: There was one role where the regenerative system was not suitable, even for Morse code sources, and that was the task of radio direction finding, or RDF.


title: Superheterodyne receiver

text: The regenerative system was highly non-linear, amplifying any signal above a certain threshold by a huge amount, sometimes so large it caused it to turn into a transmitter (which was the entire concept behind IFF). In RDF, the strength of the signal is used to determine the location of the transmitter, so one requires linear amplification to allow the strength of the original signal, often very weak, to be accurately measured.


title: Superheterodyne receiver

text: To address this need, RDF systems of the era used triodes operating below unity. To get a usable signal from such a system, tens or even hundreds of triodes had to be used, connected together anode-to-grid. These amplifiers drew enormous amounts of power and required a team of maintenance engineers to keep them running. Nevertheless, the strategic value of direction finding on weak signals was so high that the British Admiralty felt the high cost was justified.


title: Superheterodyne receiver

text: Although a number of researchers discovered the superheterodyne concept, filing patents only months apart (see below), American engineer Edwin Armstrong is often credited with the concept. He came across it while considering better ways to produce RDF receivers. He had concluded that moving to higher "short wave" frequencies would make RDF more useful and was looking for practical means to build a linear amplifier for these signals. At the time, short wave was anything above about 500 kHz, beyond any existing amplifier's capabilities.


title: Superheterodyne receiver

text: It had been noticed that when a regenerative receiver went into oscillation, other nearby receivers would start picking up other stations as well. Armstrong (and others) eventually deduced that this was caused by a "supersonic heterodyne" between the station's carrier frequency and the regenerative receiver's oscillation frequency. When the first receiver began to oscillate at high outputs, its signal would flow back out through the antenna to be received on any nearby receiver. On that receiver, the two signals mixed just as they did in the original heterodyne concept, producing an output that is the difference in frequency between the two signals.


title: Superheterodyne receiver

text: For instance, consider a lone receiver that was tuned to a station at 300 kHz. If a second receiver is set up nearby and set to 400 kHz with high gain, it will begin to give off a 400 kHz signal that will be received in the first receiver. In that receiver, the two signals will mix to produce four outputs, one at the original 300 kHz, another at the received 400 kHz, and two more, the difference at 100 kHz and the sum at 700 kHz. This is the same effect that Fessenden had proposed, but in his system the two frequencies were deliberately chosen so the beat frequency was audible. In this case, all of the frequencies are well beyond the audible range, and thus "supersonic", giving rise to the name superheterodyne.


title: Superheterodyne receiver

text: Armstrong realized that this effect was a potential solution to the "short wave" amplification problem, as the "difference" output still retained its original modulation, but on a lower carrier frequency. In the example above, one can amplify the 100 kHz beat signal and retrieve the original information from that, the receiver does not have to tune in the higher 300 kHz original carrier. By selecting an appropriate set of frequencies, even very high-frequency signals could be "reduced" to a frequency that could be amplified by existing systems.


title: Superheterodyne receiver

text: For instance, to receive a signal at 1500 kHz, far beyond the range of efficient amplification at the time, one could set up an oscillator at, for example, 1560 kHz. Armstrong referred to this as the "local oscillator" or LO. As its signal was being fed into a second receiver in the same device, it did not have to be powerful, generating only enough signal to be roughly similar in strength to that of the received station. When the signal from the LO mixes with the station's, one of the outputs will be the heterodyne difference frequency, in this case, 60 kHz. He termed this resulting difference the "intermediate frequency" often abbreviated to "IF".


title: Superheterodyne receiver

text: In December 1919, Major E. H. Armstrong gave publicity to an indirect method of obtaining short-wave amplification, called the super-heterodyne. The idea is to reduce the incoming frequency, which may be, for example 1,500,000 cycles (200 meters), to some suitable super-audible frequency that can be amplified efficiently, then passing this current through an intermediate frequency amplifier, and finally rectifying and carrying on to one or two stages of audio frequency amplification.


title: Superheterodyne receiver

text: The "trick" to the superheterodyne is that by changing the LO frequency you can tune in different stations. For instance, to receive a signal at 1300 kHz, one could tune the LO to 1360 kHz, resulting in the same 60 kHz IF. This means the amplifier section can be tuned to operate at a single frequency, the design IF, which is much easier to do efficiently.


title: Superheterodyne receiver

text: Armstrong put his ideas into practice, and the technique was soon adopted by the military. It was less popular when commercial radio broadcasting began in the 1920s, mostly due to the need for an extra tube (for the oscillator), the generally higher cost of the receiver, and the level of skill required to operate it. For early domestic radios, tuned radio frequency receivers (TRF) were more popular because they were cheaper, easier for a non-technical owner to use, and less costly to operate. Armstrong eventually sold his superheterodyne patent to Westinghouse, which then sold it to Radio Corporation of America (RCA), the latter monopolizing the market for superheterodyne receivers until 1930.


title: Superheterodyne receiver

text: Because the original motivation for the superhet was the difficulty of using the triode amplifier at high frequencies, there was an advantage in using a lower intermediate frequency. During this era, many receivers used an IF frequency of only 30 kHz. These low IF frequencies, often using IF transformers based on the self-resonance of iron-core transformers, had poor image frequency rejection, but overcame the difficulty in using triodes at radio frequencies in a manner that competed favorably with the less robust neutrodyne TRF receiver. Higher IF frequencies (455 kHz was a common standard) came into use in later years, after the invention of the tetrode and pentode as amplifying tubes, largely solving the problem of image rejection. Even later, however, low IF frequencies (typically 60 kHz) were again used in the "second" (or third) IF stage of double or triple-conversion communications receivers to take advantage of the selectivity more easily achieved at lower IF frequencies, with image-rejection accomplished in the earlier IF stage(s) which were at a higher IF frequency.


title: Superheterodyne receiver

text: In the 1920s, at these low frequencies, commercial IF filters looked very similar to 1920s audio interstage coupling transformers, had similar construction, and were wired up in an almost identical manner, so they were referred to as "IF transformers". By the mid-1930s, superheterodynes using much higher intermediate frequencies (typically around 440–470 kHz) used tuned transformers more similar to other RF applications. The name "IF transformer" was retained, however, now meaning "intermediate frequency". Modern receivers typically use a mixture of ceramic resonators or surface acoustic wave resonators and traditional tuned-inductor IF transformers.


title: Superheterodyne receiver

text: By the 1930s, improvements in vacuum tube technology rapidly eroded the TRF receiver's cost advantages, and the explosion in the number of broadcasting stations created a demand for cheaper, higher-performance receivers.


title: Superheterodyne receiver

text: The introduction of an additional grid in a vacuum tube, but before the more modern screen-grid tetrode, included the tetrode with two control grids; this tube combined the mixer and oscillator functions, first used in the so-called autodyne mixer. This was rapidly followed by the introduction of tubes specifically designed for superheterodyne operation, most notably the pentagrid converter. By reducing the tube count (with each tube stage being the main factor affecting cost in this era), this further reduced the advantage of TRF and regenerative receiver designs.


title: Superheterodyne receiver

text: By the mid-1930s, commercial production of TRF receivers was largely replaced by superheterodyne receivers. By the 1940s, the vacuum-tube superheterodyne AM broadcast receiver was refined into a cheap-to-manufacture design called the "All American Five" because it used five vacuum tubes: usually a converter (mixer/local oscillator), an IF amplifier, a detector/audio amplifier, audio power amplifier, and a rectifier. Since this time, the superheterodyne design was used for almost all commercial radio and TV receivers.


title: Superheterodyne receiver

text: French engineer Lucien Lévy filed a patent application for the superheterodyne principle in August 1917 with brevet n° 493660. Armstrong also filed his patent in 1917. Levy filed his original disclosure about seven months before Armstrong's.


title: Superheterodyne receiver

text: At first the US recognised Armstrong as the inventor, and his US Patent 1,342,885 was issued on 8 June 1920. After various changes and court hearings Lévy was awarded US patent No 1,734,938 that included seven of the nine claims in Armstrong's application, while the two remaining claims were granted to Alexanderson of GE and Kendall of AT&T.


title: Superheterodyne receiver

text: The diagram at right shows the block diagram of a typical single-conversion superheterodyne receiver. The diagram has blocks that are common to superheterodyne receivers, with only the RF amplifier being optional.


title: Superheterodyne receiver

text: The antenna collects the radio signal. The tuned RF stage with optional RF amplifier provides some initial selectivity; it is necessary to suppress the "image frequency" (see below), and may also serve to prevent strong out-of-passband signals from saturating the initial amplifier. A local oscillator provides the mixing frequency; it is usually a variable frequency oscillator which is used to tune the receiver to different stations. The frequency mixer does the actual heterodyning that gives the superheterodyne its name; it changes the incoming radio frequency signal to a higher or lower, fixed, intermediate frequency (IF). The IF band-pass filter and amplifier supply most of the gain and the narrowband filtering for the radio. The demodulator extracts the audio or other modulation from the IF radio frequency. The extracted signal is then amplified by the audio amplifier.


title: Superheterodyne receiver

text: To receive a radio signal, a suitable antenna is required. The output of the antenna may be very small, often only a few microvolts. The signal from the antenna is tuned and may be amplified in a so-called radio frequency (RF) amplifier, although this stage is often omitted. One or more tuned circuits at this stage block frequencies that are far removed from the intended reception frequency. To tune the receiver to a particular station, the frequency of the local oscillator is controlled by the tuning knob (for instance). Tuning of the local oscillator and the RF stage may use a variable capacitor, or varicap diode. The tuning of one (or more) tuned circuits in the RF stage must track the tuning of the local oscillator.


title: Superheterodyne receiver

text: The signal is then fed into a circuit where it is mixed with a sine wave from a variable frequency oscillator known as the local oscillator (LO). The mixer uses a non-linear component to produce both sum and difference beat frequencies signals, each one containing the modulation contained in the desired signal. The output of the mixer may include the original RF signal at "f", the local oscillator signal at "f", and the two new heterodyne frequencies "f" + "f" and "f" − "f". The mixer may inadvertently produce additional frequencies such as third- and higher-order intermodulation products. Ideally, the IF bandpass filter removes all but the desired IF signal at "f". The IF signal contains the original modulation (transmitted information) that the received radio signal had at "f".


title: Superheterodyne receiver

text: The frequency of the local oscillator "f" is set so the desired reception radio frequency "f" mixes to "f". There are two choices for the local oscillator frequency because the dominant mixer products are at "f" ± "f". If the local oscillator frequency is less than the desired reception frequency, it is called low-side injection ("f" = "f" − "f"); if the local oscillator is higher, then it is called high-side injection ("f" = "f" − "f").


title: Superheterodyne receiver

text: The mixer will process not only the desired input signal at f, but also all signals present at its inputs. There will be many mixer products (heterodynes). Most other signals produced by the mixer (such as due to stations at nearby frequencies) can be filtered out in the IF tuned amplifier; that gives the superheterodyne receiver its superior performance. However, if "f" is set to "f" + "f", then an incoming radio signal at "f" + "f" will "also" produce a heterodyne at "f"; the frequency "f" + "f" is called the "image frequency" and must be rejected by the tuned circuits in the RF stage. The image frequency is 2 "f" higher (or lower) than the desired frequency "f", so employing a higher IF frequency "f" increases the receiver's "image rejection" without requiring additional selectivity in the RF stage.


title: Superheterodyne receiver

text: To suppress the unwanted image, the tuning of the RF stage and the LO may need to "track" each other. In some cases, a narrow-band receiver can have a fixed tuned RF amplifier. In that case, only the local oscillator frequency is changed. In most cases, a receiver's input band is wider than its IF center frequency. For example, a typical AM broadcast band receiver covers 510 kHz to 1655 kHz (a roughly 1160 kHz input band) with a 455 kHz IF frequency; an FM broadcast band receiver covers 88 MHz to 108 MHz band with a 10.7 MHz IF frequency. In that situation, the RF amplifier must be tuned so the IF amplifier does not see two stations at the same time. If the AM broadcast band receiver LO were set at 1200 kHz, it would see stations at both 745 kHz (1200−455 kHz) and 1655 kHz. Consequently, the RF stage must be designed so that any stations that are twice the IF frequency away are significantly attenuated. The tracking can be done with a multi-section variable capacitor or some varactors driven by a common control voltage. An RF amplifier may have tuned circuits at both its input and its output, so three or more tuned circuits may be tracked. In practice, the RF and LO frequencies need to track closely but not perfectly.


title: Superheterodyne receiver

text: In the days of tube (valve) electronics, it was common for superheterodyne receivers to combine the functions of the local oscillator and the mixer in a single tube, leading to a savings in power, size, and especially cost. A single pentagrid converter tube would oscillate and also provide signal amplification as well as frequency mixing.


title: Superheterodyne receiver

text: The stages of an intermediate frequency amplifier ("IF amplifier" or "IF strip") are tuned to a fixed frequency that does not change as the receiving frequency changes. The fixed frequency simplifies optimization of the IF amplifier. The IF amplifier is selective around its center frequency "f". The fixed center frequency allows the stages of the IF amplifier to be carefully tuned for best performance (this tuning is called "aligning" the IF amplifier). If the center frequency changed with the receiving frequency, then the IF stages would have had to track their tuning. That is not the case with the superheterodyne.


title: Superheterodyne receiver

text: Normally, the IF center frequency "f" is chosen to be less than the range of desired reception frequencies "f". That is because it is easier and less expensive to get high selectivity at a lower frequency using tuned circuits. The bandwidth of a tuned circuit with a certain Q is proportional to the frequency itself (and what's more, a higher Q is achievable at lower frequencies), so fewer IF filter stages are required to achieve the same selectivity. Also, it is easier and less expensive to get high gain at a lower frequencies.


title: Superheterodyne receiver

text: However, in many modern receivers designed for reception over a wide frequency range (e.g. scanners and spectrum analyzers) a first IF frequency "higher" than the reception frequency is employed in a double conversion configuration. For instance, the Rohde & Schwarz EK-070 VLF/HF receiver covers 10 kHz to 30 MHz. It has a band switched RF filter and mixes the input to a first IF of 81.4 MHz and a second IF frequency of 1.4 MHz. The first LO frequency is 81.4 to 111.4 MHz, a reasonable range for an oscillator. But if the original RF range of the receiver were to be converted "directly" to the 1.4 MHz intermediate frequency, the LO frequency would need to cover 1.4-31.4 MHz which cannot be accomplished using tuned circuits (a variable capacitor with a fixed inductor would need a capacitance range of 500:1). Image rejection is never an issue with such a high IF frequency. The first IF stage uses a crystal filter with a 12 kHz bandwidth. There is a second frequency conversion (making a triple-conversion receiver) that mixes the 81.4 MHz first IF with 80 MHz to create a 1.4 MHz second IF. Image rejection for the second IF is not an issue as the first IF has a bandwidth of much less than 2.8 MHz.


title: Superheterodyne receiver

text: To avoid interference to receivers, licensing authorities will avoid assigning common IF frequencies to transmitting stations. Standard intermediate frequencies used are 455 kHz for medium-wave AM radio, 10.7 MHz for broadcast FM receivers, 38.9 MHz (Europe) or 45 MHz (US) for television, and 70 MHz for satellite and terrestrial microwave equipment. To avoid tooling costs associated with these components, most manufacturers then tended to design their receivers around a fixed range of frequencies offered, which resulted in a worldwide "de facto" standardization of intermediate frequencies.


title: Superheterodyne receiver

text: In early superhets, the IF stage was often a regenerative stage providing the sensitivity and selectivity with fewer components. Such superhets were called super-gainers or regenerodynes. This is also called a Q multiplier, involving a small modification to an existing receiver especially for the purpose of increasing selectivity.


title: Superheterodyne receiver

text: The IF stage includes a filter and/or multiple tuned circuits to achieve the desired selectivity. This filtering must have a band pass equal to or less than the frequency spacing between adjacent broadcast channels. Ideally a filter would have a high attenuation to adjacent channels, but maintain a flat response across the desired signal spectrum in order to retain the quality of the received signal. This may be obtained using one or more dual tuned IF transformers, a quartz crystal filter, or a multipole ceramic crystal filter.


title: Superheterodyne receiver

text: In the case of television receivers, no other technique was able to produce the precise bandpass characteristic needed for vestigial sideband reception, such as that used in the NTSC system first approved by the US in 1941. By the 1980s, multi-component capacitor-inductor filters had been replaced with precision electromechanical surface acoustic wave (SAW) filters. Fabricated by precision laser milling techniques, SAW filters are cheaper to produce, can be made to extremely close tolerances, and are very stable in operation.


title: Superheterodyne receiver

text: The received signal is now processed by the demodulator stage where the audio signal (or other baseband signal) is recovered and then further amplified. AM demodulation requires envelope detection, which can be achieved by means of rectification and a low-pass filter (which can be as simple as an RC circuit) to remove remnants of the intermediate frequency. FM signals may be detected using a discriminator, ratio detector, or phase-locked loop. Continuous wave and single sideband signals require a product detector using a so-called beat frequency oscillator, and there are other techniques used for different types of modulation. The resulting audio signal (for instance) is then amplified and drives a loudspeaker.


title: Superheterodyne receiver

text: When so-called high-side injection has been used, where the local oscillator is at a "higher" frequency than the received signal (as is common), then the frequency spectrum of the original signal will be reversed. This must be taken into account by the demodulator (and in the IF filtering) in the case of certain types of modulation such as single sideband.


title: Superheterodyne receiver

text: To overcome obstacles such as image response, some receivers use multiple successive stages of frequency conversion and multiple IFs of different values. A receiver with two frequency conversions and IFs is called a "dual conversion superheterodyne", and one with three IFs is called a "triple conversion superheterodyne".


title: Superheterodyne receiver

text: The main reason that this is done is that with a single IF there is a tradeoff between low image response and selectivity. The separation between the received frequency and the image frequency is equal to twice the IF frequency, so the higher the IF, the easier it is to design an RF filter to remove the image frequency from the input and achieve low image response. However, the higher the IF, the more difficult it is to achieve high selectivity in the IF filter. At shortwave frequencies and above, the difficulty in obtaining sufficient selectivity in the tuning with the high IFs needed for low image response impacts performance. To solve this problem two IF frequencies can be used, first converting the input frequency to a high IF to achieve low image response, and then converting this frequency to a low IF to achieve good selectivity in the second IF filter. To improve tuning, a third IF can be used.


title: Superheterodyne receiver

text: For example, for a receiver that can tune from 500 kHz to 30 MHz, three frequency converters might be used. With a 455 kHz IF it is easy to get adequate front end selectivity with broadcast band (under 1600 kHz) signals. For example, if the station being received is on 600 kHz, the local oscillator can be set to 1055 kHz, giving an image on (-600+1055=) 455 kHz. But a station on 1510 kHz could also potentially produce an image at (1510-1055=) 455 kHz and so cause image interference. However, because 600 kHz and 1510 kHz are so far apart, it is easy to design the front end tuning to reject the 1510 kHz frequency.


title: Superheterodyne receiver

text: However at 30 MHz, things are different. The oscillator would be set to 30.455 MHz to produce a 455 kHz IF, but a station on 30.910 would also produce a 455 kHz beat, so both stations would be heard at the same time. But it is virtually impossible to design an RF tuned circuit that can adequately discriminate between 30 MHz and 30.91 MHz, so one approach is to "bulk downconvert" whole sections of the shortwave bands to a lower frequency, where adequate front-end tuning is easier to arrange.


title: Superheterodyne receiver

text: For example, the ranges 29 MHz to 30 MHz; 28 MHz to 29 MHz etc. might be converted down to 2 MHz to 3 MHz, there they can be tuned more conveniently. This is often done by first converting each "block" up to a higher frequency (typically 40 MHz) and then using a second mixer to convert it down to the 2 MHz to 3 MHz range. The 2 MHz to 3 MHz "IF" is basically another self-contained superheterodyne receiver, most likely with a standard IF of 455 kHz.


title: Superheterodyne receiver

text: Microprocessor technology allows replacing the superheterodyne receiver design by a software-defined radio architecture, where the IF processing after the initial IF filter is implemented in software. This technique is already in use in certain designs, such as very low-cost FM radios incorporated into mobile phones, since the system already has the necessary microprocessor.


title: Superheterodyne receiver

text: Radio transmitters may also use a mixer stage to produce an output frequency, working more or less as the reverse of a superheterodyne receiver.


title: Superheterodyne receiver

text: Superheterodyne receivers have essentially replaced all previous receiver designs. The development of modern semiconductor electronics negated the advantages of designs (such as the regenerative receiver) that used fewer vacuum tubes. The superheterodyne receiver offers superior sensitivity, frequency stability and selectivity. Compared with the tuned radio frequency receiver (TRF) design, superhets offer better stability because a tuneable oscillator is more easily realized than a tuneable amplifier. Operating at a lower frequency, IF filters can give narrower passbands at the same Q factor than an equivalent RF filter. A fixed IF also allows the use of a crystal filter or similar technologies that cannot be tuned. Regenerative and super-regenerative receivers offered a high sensitivity, but often suffer from stability problems making them difficult to operate.


title: Superheterodyne receiver

text: Although the advantages of the superhet design are overwhelming, there are a few drawbacks that need to be tackled in practice.


title: Superheterodyne receiver

text: One major disadvantage to the superheterodyne receiver is the problem of "image frequency". In heterodyne receivers, an image frequency is an undesired input frequency equal to the station frequency plus (or minus) twice the intermediate frequency. The image frequency results in two stations being received at the same time, thus producing interference. Reception at the image frequency can be combated through tuning (filtering) at the antenna and RF stage of the superheterodyne receiver.


title: Superheterodyne receiver

text: For example, an AM broadcast station at 580 kHz is tuned on a receiver with a 455 kHz IF. The local oscillator is tuned to 1035 kHz. But a signal at 1490 kHz is also 455 kHz away from the local oscillator; so both the desired signal and the image, when mixed with the local oscillator, will appear at the intermediate frequency. This image frequency is within the AM broadcast band. Practical receivers have a tuning stage before the converter, to greatly reduce the amplitude of image frequency signals; additionally, broadcasting stations in the same area have their frequencies assigned to avoid such images.


title: Superheterodyne receiver

text: The unwanted frequency is called the "image" of the wanted frequency, because it is the "mirror image" of the desired frequency reflected about formula_2. A receiver with inadequate filtering at its input will pick up signals at two different frequencies simultaneously: the desired frequency and the image frequency. A radio reception which happens to be at the image frequency can interfere with reception of the desired signal, and noise (static) around the image frequency can decrease the receiver's signal-to-noise ratio (SNR) by up to 3dB.


title: Superheterodyne receiver

text: Early Autodyne receivers typically used IFs of only 150 kHz or so. As a consequence, most Autodyne receivers required greater front-end selectivity, often involving double-tuned coils, to avoid image interference. With the later development of tubes able to amplify well at higher frequencies, higher IF frequencies came into use, reducing the problem of image interference. Typical consumer radio receivers have only a single tuned circuit in the RF stage.


title: Superheterodyne receiver

text: Sensitivity to the image frequency can be minimized only by (1) a filter that precedes the mixer or (2) a more complex mixer circuit to suppress the image; this is rarely used. In most tunable receivers using a single IF frequency, the RF stage includes at least one tuned circuit in the RF front end whose tuning is performed in tandem with the local oscillator. In double (or triple) conversion receivers in which the first conversion uses a fixed local oscillator, this may rather be a fixed bandpass filter which accommodates the frequency range being mapped to the first IF frequency range.


title: Superheterodyne receiver

text: Image rejection is an important factor in choosing the intermediate frequency of a receiver. The farther apart the bandpass frequency and the image frequency are, the more the bandpass filter will attenuate any interfering image signal. Since the frequency separation between the bandpass and the image frequency is formula_3, a higher intermediate frequency improves image rejection. It may be possible to use a high enough first IF that a fixed-tuned RF stage can reject any image signals.


title: Superheterodyne receiver

text: The ability of a receiver to reject interfering signals at the image frequency is measured by the image rejection ratio. This is the ratio (in decibels) of the output of the receiver from a signal at the received frequency, to its output for an equal-strength signal at the image frequency.


title: Superheterodyne receiver

text: It can be difficult to keep stray radiation from the local oscillator below the level that a nearby receiver can detect. If the receiver's local oscillator can reach the antenna it will act as a low-power CW transmitter. Consequently, what is meant to be a receiver can itself create radio interference.


title: Superheterodyne receiver

text: In intelligence operations, local oscillator radiation gives a means to detect a covert receiver and its operating frequency. The method was used by MI5 during Operation RAFTER. This same technique is also used in radar detector detectors used by traffic police in jurisdictions where radar detectors are illegal.


title: Superheterodyne receiver

text: Local oscillator radiation is most prominent in receivers in which the antenna signal is connected directly to the mixer (which itself receives the local oscillator signal) rather than from receivers in which an RF amplifier stage is used in between. Thus it is more of a problem with inexpensive receivers and with receivers at such high frequencies (especially microwave) where RF amplifying stages are difficult to implement.


title: Superheterodyne receiver

text: Local oscillators typically generate a single frequency signal that has negligible amplitude modulation but some random phase modulation which spreads some of the signal's energy into sideband frequencies. That causes a corresponding widening of the receiver's frequency response, which would defeat the aim to make a very narrow bandwidth receiver such as to receive low-rate digital signals. Care needs to be taken to minimize oscillator phase noise, usually by ensuring that the oscillator never enters a non-linear mode.


title: 2021 UEFA Super Cup

text: The 2021 UEFA Super Cup was the 46th edition of the UEFA Super Cup, an annual football match organised by UEFA and contested by the winners of the two main European club competitions, the UEFA Champions League and the UEFA Europa League. The match featured English club Chelsea, the winners of the 2020–21 UEFA Champions League, and Spanish club Villarreal, the winners of the 2020–21 UEFA Europa League. It was played at Windsor Park, Belfast, Northern Ireland, on 11 August 2021.


title: 2021 UEFA Super Cup

text: Chelsea won the match 6–5 on penalties following a 1–1 draw after extra time for their second UEFA Super Cup title.


title: 2021 UEFA Super Cup

text: The match was the first UEFA club competition final to be played in Northern Ireland. The 18,500-capacity Windsor Park is the home of Linfield and the Northern Ireland national team. Opened in 1905, the stadium was most recently renovated from 2014 to 2016 with aid from UEFA's HatTrick assistance programme. The venue previously hosted the finals of the 2005 UEFA European Under-19 Championship and 2017 UEFA Women's Under-19 Championship.


title: 2021 UEFA Super Cup

text: An open bidding process was launched on 28 September 2018 by UEFA to select the venues of the finals of the UEFA Champions League, UEFA Europa League, and UEFA Women's Champions League in 2021. Associations had until 26 October 2018 to express interest, and bid dossiers must be submitted by 15 February 2019.


title: 2021 UEFA Super Cup

text: UEFA announced on 1 November 2018 that four associations had expressed interest in hosting the 2021 UEFA Super Cup, and on 22 February 2019 that all four associations submitted their dossiers by the deadline.


title: 2021 UEFA Super Cup

text: Windsor Park was selected by the UEFA Executive Committee during their meeting in Ljubljana, Slovenia on 24 September 2019.


title: 2021 UEFA Super Cup

text: On 6 August 2021, UEFA named Russian official Sergei Karasev as the referee for the match. Karasev had been a FIFA referee since 2010, and officiated at UEFA Euro 2016, the 2018 FIFA World Cup and UEFA Euro 2020. He was joined by fellow countrymen Igor Demeshko and Maksim Gavrilin as assistant referees, while Aleksei Kulbakov of Belarus served as the fourth official. Marco Fritz of Germany was selected as the video assistant referee (VAR), with Paweł Gil of Poland and Massimiliano Irrati of Italy serving as the assistant VAR officials. Irrati's countryman Filippo Meli was selected as the reserve assistant referee.


title: 2021 UEFA Super Cup

text: Chelsea opened the scoring after 27 minutes when Kai Havertz's low cross from the left was swept into the net by Hakim Ziyech from seven yards out. Ziyech was substituted after a shoulder injury just before half-time. Alberto Moreno hit a volley off the underside of the crossbar in first-half injury time. Villarreal equalised in the 73rd minute when Gerard Moreno scored with a clinical right-foot finish to the top left corner of the net after a flick-back from Boulaye Dia on the right of the penalty area.


title: 2021 UEFA Super Cup

text: The match went to extra-time with Chelsea goalkeeper Édouard Mendy being replaced in the last minute by Kepa Arrizabalaga. Arrizabalaga saved two penalties, the decisive one low to his right from Raúl Albiol allowed Chelsea to win 6–5 in the shoot-out.


title: Guided missiles of India

text: India has studied, produced and used various strategic and tactical missile systems since its independence. Decades long projects have realised development of all types of missile systems including ballistic, cruise, anti-ship, air-defence, air-to-air and anti-missile systems. India is one of seven countries in the world with intercontinental ballistic missiles (ICBMs) and one of four countries with anti-ballistic missile systems. Since 2016, India has been a member of Missile Technology Control Regime (MTCR).


title: Guided missiles of India

text: The use of rockets for warfare in India has been recorded in as early as the 18th century. Mysorean rockets were the first iron-cased rockets in world that were successfully deployed for military use. Mysore's conflict with East India Company exposed British to the technology leading to development of Congreve rockets and introduction of rocketry in Europe.


title: Guided missiles of India

text: Research in missile technology resumed again after India's independence along with the weapons of mass destruction. Development of nuclear weapons was followed by various missile programs in 70s with development of various ballistic, cruise, surface to air, anti- ballistic missile and orbital launch systems. India conducted its first nuclear test and initiated with Project Devil as an attempt to reverse engineer Soviet surface to air missile SA-2 Guideline and Project Valiant to develop an intercontinental ballistic missile. However, it could not succeed and experience gained led to development of Prithvi series of short range ballistic-missiles. In early 80s, India conducted its first successful orbital launch and synchronized its research institutions under IGMDP and successfully developed a series of strategic missile systems. The project began in early 1980s and ended in 2008, after these strategic missiles were successfully developed. The last major missile developed under the program was the Agni 3 intermediate-range ballistic missile which was successfully tested on 9 July 2007. Since then, India has developed, tested, operationalized, and is developing several missile systems that are limited to only a handful of countries including ICBMs, ASATs, SLBMs and hypersonic weapon systems. Threats posed by enemy missile systems led to the pursuit of Indian Ballistic Missile Defense Programme.


title: Guided missiles of India

text: In 2017, India produced most of defined MTCR defined missile technologies required to be integrated to produce most missile systems. As per G Satheesh Reddy, India achieved complete self reliance in missile technology.


title: Guided missiles of India

text: Mysorean rockets were the first iron-cased rockets that were successfully deployed for military use. Kingdom of Mysore utilised them effectively in the conflicts against the British East India Company. In addition, wheeled rocket launchers capable of launching five to ten rockets almost simultaneously were used in war. These rockets were re-engineered as Congreve rockets by British opening the door of development of advanced rocketry further in Europe.


title: Guided missiles of India

text: Indian government constituted a teamd Special Weapons Development Team in 1958 to study guided missile systems.


title: Guided missiles of India

text: The phase-I of missile program was limited to development of a first generation anti-tank guided missile (ATGM) by DRDO. Liquid fuel rocket engines based on Soviet missile system SA-2 were developed. Despite the overall failure of DRDO to develop a reliable ATGM, Indian laboratories had established facilities useful for machining and fabricating various parts of missile systems including gyroscopes, actuators, silver oxide-zinc


title: Guided missiles of India

text: nisms, and wire spool winding and reeling mechanisms. India later excepted the French offer to produce SS-11B anti-tank guided missiles in 1970s. In another phase initiated in 1970s, Project Devil to reverse engineer Soviet SA-2 Guideline and Project Valiant to develop an Inter-continental ballistic missile too ended up with limited success but imparting experience and facilities for further research on missiles and space rockets. DRDO simultaneously focused on building a guidance package – an essential part of a long-range missile that determines its path and accuracy to hit a target. A platform-based inertial navigation system (INS) was developed and tested, on board an Avro aircraft, in 1974–75. Subsequently, an INS was built for both missiles and an aircraft, and this was tested in 1979 on board a Canberra aircraft. Decade of 1980s witnessed India gaining significant grounds in rocket technology and various technology demonstration programs began which became the basis of modern rocket systems in India. DRDL had developed competencies in the fields of propulsion, navigation and manufacture of materials. Indian Space Research Organisation had successfully tested India's first orbital rocket SLV-3 in 1980 whose first stage was used in Agni-TD ballistic missile for technological demonstration of Agni missile family. This subsequently led to the birth of the Integrated Guided Missile Development Program and Dr. Abdul Kalam, who had previously been the project director for the SLV-3 programme at ISRO, was inducted as the DRDL Director in 1983 to conceive and lead it. He decided that DRDL would pursue multiple projects in this area simultaneously. Thus, four projects were born under the IGMDP; Short range surface-to-surface missile (code-named Prithvi), Short range low-level surface-to-air missile (code-named Trishul), Medium range surface-to-air missile (code-named Akash) and Third-generation anti-tank missile (code-named Nag).


title: Guided missiles of India

text: The Agni missile was initially conceived in the IGMDP as a technology demonstrator project in the form of a re-entry vehicle, and was later upgraded to a ballistic missile with different ranges. As part of this program, the Interim Test Range at Balasore in Orissa was also developed for missile testing.


title: Guided missiles of India

text: The fourth phase of India's missile program stretched from mid-1990s to early 21st century. BJP's tendency to nuclearise India's military has boosted the development and production of missiles. The phase has witnessed limited series production of DRDO's missiles and their deployment in battlefields. DRDO further embarked on programs in developing submarine launched ballistic missile Sagarika, cruise missiles BrahMos, naval variant of Prithvi Dhanush. Spanning from 1970s to 2000s, India's missile programs have transitioned into a self-sustaining character. Over the period from then, India has made improvements in technology of its missile systems and has produced many missile systems including ICBMs, anti-ballistic missiles, air-to-air missiles, cruise missiles and other systems.


title: Guided missiles of India

text: After India test-fired the first Prithvi missile in 1988, and the Agni missile in 1989, the Missile Technology Control Regime (then an informal grouping established in 1987 by Canada, France, Germany, Italy, Japan, the United Kingdom and the United States) decided to restrict access to any technology that would help India in its missile development program. Some of the major technology which was denied, included:


title: Guided missiles of India

text: To counter the MTCR, the IGMDP team formed a consortium of DRDO laboratories, industries and academic institutions to build these sub-systems, components and materials. Though this slowed down the progress of the program, India successfully developed indigenously all the restricted components denied to it by the MTCR.


title: Guided missiles of India

text: In 2011, the DRDO Chief V K Saraswat had stated that "indigenous content" in India's strategic missiles had gone up to such a level, with ring-laser gyros, composite rocket motors, micro-navigation systems etc., that "no technology control regime" could derail them any longer.


title: Guided missiles of India

text: In 1959, Indian agencies conducted feasibility study to develop a first generation wire guided anti-tank missile.DRDO Anti Tank Missile. Sino-Indian war in 1962 induced the government to fund the project. Designing and wind tunnel tests went on to develop an ATGM of a range of 0.5 to 2 km with flight speed of about 90 m/s. The missile was terminated eventually in 1969 once Indian army upgraded its requirements of an ATGM of range from 1.6 km to 2 km.


title: Guided missiles of India

text: The aim of Project Devil was to reverse engineer Soviet SA-2 Guideline missile to produce an indigenous short range surface to air missile. The program initially waned in favour of Project Valiant but was revived later after 1974. Although DRDL had developed and tested various systems for the missile, it later was completely cancelled in 1980 due to disputes between officials and technologies were utilised in other missile programs.


title: Guided missiles of India

text: Project Valiant was one of two early liquid-fuelled missile projects developed by India, along with Project Devil in the 1970s. The goal of Project Valiant was to produce an ICBM with 30 tonne engines and a range of . Valiant missile was envisaged as an 85 tonnes liquid fueled three-staged ICBM. The missile although could reach near the stages of grounding testing, DRDO's interest in program waned due to internal disputes. ISRO was later approached with an offer to use missile for civilian uses which they declined leading to overall closure of the project. Although discontinued in 1974 without achieving full success, Project Valiant, like Project Devil, helped in the development of the Prithvi missile in the 1980s. Though never reached fruition, the projects were important precursors to the Prithvi missile developed in the 1980s.


title: Guided missiles of India

text: Trishul was a short range surface to air missile to be used against low flying and sea-skimming targets. The range of the missile is 12 km and is fitted with a 15 kg warhead. The overall weight of the missile is 130 kg. Due to delay in development time and various deficiencies, Trishul could never enter production and service beyond testing and was substituted by Israeli Barak 1 missile. The project was officially closed in 2008 and DRDO embarked on more surface to air missile programs later.


title: Guided missiles of India

text: The Integrated Guided Missile Development Program (IGMDP) was a Ministry of Defence (India) programme for the research and development of a comprehensive range of missiles. The program was managed by the Defence Research and Development Organisation (DRDO) and Ordnance Factories Board in partnership with other Indian government research organisations. The program envisaged development of five strategic systems. Prithvi series of short ranged ballistic missiles, Trishul low altitude, short range surface to air missile, Akash medium range surface to air missile and Nag third generation anti-tank guided missile followed by Agni series of medium and long range ballistic missiles. The project began in early 1980s and ended in 2008 after these strategic missiles were successfully developed. The last major missile developed under the program was the Agni 3 intermediate-range ballistic missile which was successfully tested on 9 July 2007.


title: Guided missiles of India

text: On 8 January 2008, the DRDO formally announced the successful completion of the IGMDP. It added that the strategic integrated guided missile program was completed with its design objectives achieved since most of the missiles in the program had been developed and inducted by the Indian armed forces.


title: Guided missiles of India

text: Further variants of Prithvi missile, Akash-NG, Agni-IV, Agni-V, Agni-VI and Agni based K missile family went ahead later as independent projects.


title: Guided missiles of India

text: Akash is a medium-range mobile surface-to-air missile system developed by the Defence Research and Development Organisation (DRDO), Ordnance Factories Board and Bharat Electronics Limited (BEL) in India. The missile system can target aircraft, cruise missiles, air to surface missiles and ballistic missiles up to 30 km to 60  km away, at altitudes up to 18,000 m. Variants like Akash-1S and Akash-NG have longer ranges, higher accuracy, higher mobility and lower reaction time.


title: Guided missiles of India

text: Nag, also referred as Prospina, is the currently serving third generation "Fire-and-forget" anti-tank guided missile developed under the Integrated Guided Missile Development Program (IGMDP). Nag has been developed at a cost of . Nag has an operational range from 500 m to and first shot hit probability exceeding 90%. Nag also has its man-portable, helicopter mounted, Stand-off and IFV mounted versions.


title: Guided missiles of India

text: Besides Nag, BDL's Amogha series is currently undergoing trials and will have land-attack, man-portable and air launched variants. Armament Research and Development Establishment (ARDE) is testing a laser guided, tank gun launched SAMHO missile able to destroy tanks and low flying helicopters. Besides state-run programmes, Indian private firms have been emerging with ATGM systems.


title: Guided missiles of India

text: Prithvi missiles were tactical surface-to-surface short-range ballistic missiles (SRBM) and were first ballistic missiles to be developed and enter service in India. It goes from Prithvi-I (SS-150) with range to Prithvi-II (SS-250) and Prithvi-III (SS-350) with ranges of up to . Dhanush or navalised Prithvi is a system consisting of a stabilisation platform (Bow) and the Missile (Arrow). It is intended for the Indian Navy, to be fired from ships against other ships or land targets. Dhanush can fire modified versions of Prithvi-II or Prithvi-III with ranges high as .


title: Guided missiles of India

text: Solid fueled Prahar and Pranash are being tested to replace existing Prithvi missiles. Export variant "Pragati" was exhibited in South Korea in 2013 but didn't receive any orders. Pralay is another battlefield range ballistic missile with better range being developed from PDV anti-ballistic missile.


title: Guided missiles of India

text: The Agni missile series began as a "Re-Entry Vehicle" project (later rechristened as Agni Technology Demonstrator) in the IGMDP. It subsequently gave rise to the series of India's medium range, intermediate range and intercontinental ballistic missiles. Agni-I, Agni-II and Agni-III missiles were developed under the Integrated Guided Missile Development Program.


title: Guided missiles of India

text: Longer range Agni-IV and Agni-V with intercontinental ranges and MIRV emerged in early 2010s as separate projects.


title: Guided missiles of India

text: Agni-P, an upgraded successor of Agni-I and Agni-II was tested in 2021 with ability to carry maneuverable reentry vehicle (MaRV). Agni-P has improved propellant, navigation and guided systems and reportedly can be used as an ASBM against aircraft carriers.


title: Guided missiles of India

text: Agni-VI is another Intercontinental ballistic missile reported to be in rudimentary stages of development by India, and until May 2012 was not officially confirmed by either the Government of India or the DRDO. Reportedly, it will be able to be launched from submarines or from land and to strike a target of over with MIRV-ed warheads. Top DRDO scientists have previously asserted that India has almost all the equipment and technology needed to develop ICBMs, "but where the warhead should go or what the range should be will have to be a political call". In 1995 in a report published by magazine Nonproliferation review, DRDO was working on an ICBM called Surya with a range of . Although, the actual status of missile always remained unknown in public domain. Sources have speculated that Agni-VI might be Surya under new codename.


title: Guided missiles of India

text: K (named after Abdul Kalam) are submarine-launched ballistic missiles (SLBM) of India. SLBM variants of Agni missiles meant to arm India's nuclear submarines, their ranges vary from medium-range K-15 to intercontinental range K-6 (missile).


title: Guided missiles of India

text: The Shaurya missile is a land attack variant of K-15 missile. The missile has a hypersonic speed and a hybrid ballistic-cruise trajectory.


title: Guided missiles of India

text: BrahMos (also known as PJ-10) are supersonic to hypersonic cruise missiles developed in collaboration between India and Russia. BrahMos have land attack, ship and submarine launched and air launched versions and are the fastest cruise missiles in world in operation. The existing versions of missiles include supersonic land-attack, anti-ship ship launched versions meanwhile longer range, hypersonic and air launched versions are under development.


title: Guided missiles of India

text: Nirbhay is the Indian long range sub-sonic Cruise Missile under development and testing, expecting its air and submarine launched version after trials. It was successfully test fired for second time from Balasore Orissa.


title: Guided missiles of India

text: Able to travel at speed of 0.6-0.9 mach. However, its test on 12 October 2020 failed due to a technical snag. It has succeeded in other tests before and has been approved for limited production in 2020. An upgraded version of the missile is reportedly under development. It is currently deployed on LAC in limited numbers since 2020 due to 2020 China-India standoff.


title: Guided missiles of India

text: Nirbhay project is now technically closed after completing six developmental trials. The next phase of tests will happen from April 2020 under a new name called Indigenous Technology Cruise Missile (ITCM). It will include Short Turbo Fan Engine (STFE) developed by Gas Turbine Research Establishment (GTRE) and a Radio-frequency (RF) seeker from Research Centre Imarat (RCI). A separate air-launched variant and submarine-launched variant is under active development. Several cruise missile systems are expected to be introduced from experience gained with Nirbhay.


title: Guided missiles of India

text: Astra are India's fifth-generation beyond-visual-range active radar homing air-to-air missile series. The current version in service has a range from to similar to AIM-120 AMRAAM while versions up to and intermediate ranges are being developed.


title: Guided missiles of India

text: A surface to air missile variant VL-SRSAM has also been developed from Astra to replace Indian navy's Barak 1 missiTN1 With supplementary Akash missile systems along, it forms a surface to air missile system similar to American NASAM 2.


title: Guided missiles of India

text: In wake of missile threats from China and Pakistan, the development of anti-ballistic missiles began in the late 1990s. The program consists of multiple phases and components. Phase-I of program is a double-tiered system consisting of two land and sea-based interceptor missiles, namely the Prithvi Air Defence (PAD) missile for high altitude interception, and the Advanced Air Defence (AAD) Missile for lower altitude interception. The two-tiered shield should be able to intercept any incoming missile launched from 5,000 kilometres away. The system also includes an overlapping network of early warning and tracking radars, as well as command and control posts. Phase-I is awaiting government's approval for installation over national capital. Phase-II would include more potent AD-1 and AD-2 anti-ballistic missiles capable of engaging without IRBMs, ICBMs and hypersonic cruise missiles. Prithvi Defence Vehicle (PDV) Mk. 1 and II are also under trials to intercept missiles at higher altitude and longer ranges and replace existing PAD. PDV Mk. 2 has also demonstrated anti-satellite capability.


title: Guided missiles of India

text: Hypersonic Technology Demonstrator Vehicle (HSTDV) is a technology demonstrator aimed to demonstrate autonomous flight of a Scramjet Integrated Vehicle using ethylene. The technology is expected to become the basis of India's hypersonic missiles and aircraft in future. India has developed an Anti-Radiation Missile (ARM) that will help to destroy enemy advance warning systems. This was named as Rudram-1, with a range of 100–250 km. Production of the ARM is being done on a priority basis by the Defence Research and Development Laboratory (DRDL), which specialises in missile development.


title: Guided missiles of India

text: Current missile research and development in India happens under the Defence Research and Development Laboratory (DRDL), and a group of laboratories collectively called the Missile Complex Laboratories.


title: Lovebug

text: The lovebug ("Plecia nearctica") is a species of march fly found in parts of Central America and the southeastern United States, especially along the Gulf Coast. It is also known as the honeymoon fly or double-headed bug. During and after mating, matured pairs remain together, even in flight, for up to several days.


title: Lovebug

text: The species was first described in 1940 by D. E. Hardy, but was seen in Louisiana as early as 1911. At that time, he reported the incidence of lovebugs to be widespread, but most common in Texas, Florida, Alabama, Mississippi, and Louisiana. However, by the end of the 20th century the species had spread heavily to all areas bordering the Gulf of Mexico, as well as Georgia and South Carolina. They are also present in other countries including Australia. L. A. Hetrick, writing in 1970, found the bug was also widespread in central and northern Florida and described its flights as reaching altitudes of and extending several kilometers over the Gulf.


title: Lovebug

text: Lovebugs' larvae feed on partially decayed vegetation in the landscape and, in this respect, are beneficial to humans. Adults primarily feed on nectar from various plants, particularly sweet clover, goldenrod, and Brazilian pepper.


title: Lovebug

text: Localized lovebug flights can number in the millions. Male/female pairs (joined tail-to-tail) will hover in the air, drifting slowly. Two major flights occur each year; the spring flight occurs during late April and May, and the summer flight occurs during late August and September. Flights extend over periods of four to five weeks. In south Florida, a third (but smaller) flight can occur in December. Mating takes place almost immediately after emergence of the females. Adult females live only three to four days, while males live a little longer. They have to stick to each other at all times.


title: Lovebug

text: This species' reputation as a public nuisance is due not to any bite or sting (it is incapable of either), but to its slightly acidic body chemistry. There are no health risks to humans, as disease cannot be transmitted through them. Because airborne lovebugs can exist in enormous numbers near highways, they die in large numbers on automobile windshields, hoods, and radiator grilles when vehicles travel at highway speeds. If left for more than an hour or two, the remains become extremely difficult to remove. Their body chemistry has a nearly neutral 6.5 pH but may become acidic at 4.25 pH if left on the car for a day. In the past, the acidity of the dead adult body, especially the female's egg masses, often resulted in pits and etches in automotive paint and chrome if not quickly removed. However, advances in automotive paints and protective coatings have reduced this threat significantly. Now the greatest concern is excessive clogging of vehicle radiator air passages by the bodies of the adults, with a reduction of the cooling effect on engines, and the obstruction of windshields when the remains of the adults and egg masses are smeared on the glass.


title: Lovebug

text: Lovebug adults are attracted to light-colored surfaces, especially if they are freshly painted, but adults congregate almost anywhere, apparently reacting to the effects of sunlight on automobile fumes, asphalt, and other products affected by environmental factors still not completely understood.


title: Lovebug

text: Urban legend holds that lovebugs are synthetic—the result of a University of Florida genetics experiment gone wrong.


title: Lovebug

text: Research by L.L. Buschman showed that migration explained the introduction of the lovebug into Florida and other southeastern states, contrary to the urban myth that the University of Florida created them by manipulating DNA to control mosquito populations.


title: Lovebug

text: Much speculation about the lovebug still thrives. This is partly because the larval form of this insect is seldom seen, as it lives and feeds in the thatch of grasses for most of the year. While various fungi are suspected of being natural controls for this species, biological control of these non-pest flies is not a priority for funding.


title: Lovebug

text: Lovebugs are subject to some significant natural controls, such as various parasitic fungi, and dry weather, which dries out the thatch, resulting in a higher mortality rate for the immature. As the lovebug migrated around the Gulf Coast, first to Texas, then Louisiana, then further eastward, the initial populations for many years were so excessive that they caused public concern and initiated rumors of their origin. However, as pest populations migrate naturally, their natural controls are usually not far behind. While it often took decades, lovebug flights are no longer present in the huge numbers that once existed simply because their natural controls (mostly fungi) caught up with established populations. In many areas, local lovebug flights may only be present in excessively large numbers due to occasional local conditions that may not be repeated in successive years.


title: Lovebug

text: While lovebugs are not a favored food of most insectivores due to their acidic taste, lovebug larvae—and some adults—are food for birds such as quail and robins. Arthropod predators include spiders, some predatory insects such as earwigs, at least two species of beetle larvae, and centipedes.


title: Lovebug

text: Female lovebugs can lay as many as 100-350 eggs and regularly lay these eggs around decaying material on the top layer of ground soil. Lovebug eggs generally hatch after 2–4 days, depending on flight season. Once the eggs have hatched, the larvae start feeding on the decaying material around them, such as decaying plants on the soil and other organic material, and live and remain in the soil until they develop to the pupa stage. During the warmer months the lovebug larvae remain in the larvae phase for approximately 120 days and approximately 240 days during the cooler months. Lovebugs typically stay in the pupa stage about 7–9 days before reaching the adult phase, in which they can start reproducing.


title: Lovebug

text: Once adults, lovebugs are ready to start copulating to begin reproducing. Adult male lovebugs emerge first from the pupal stage and hover around until female lovebugs emerge. Mating between lovebugs takes place immediately after emergence of the adult females. A male lovebug copulates and will remain paired up until the female has been fully fertilized. Copulation takes place for 2–3 days before the female detaches, lays her eggs, and dies. Adult females have been recorded to live up to seven days, while adult males may live up to two to five days, but on average lovebugs live three to four days. However, Thornhill (1976c) recorded recapture data that showed males lived longer in the field than females.


title: Luke Benward

text: Luke Aaron Benward (born May 12, 1995) is an American actor and singer. He is best known for his role as Will in the Disney film "Cloud 9" (2014). His first starring role was Billy Forrester in "How to Eat Fried Worms" (2006), and as Charlie Tuttle in "Minutemen" (2008). He played the role of Dillon in "Ravenswood" and Bo in the Netflix film "Dumplin'". He recurred as Teddy's boyfriend, Beau, on the final season of the Disney Channel series "Good Luck Charlie".


title: Luke Benward

text: Benward was born in Franklin, Tennessee, the son of Kenda (née Wilkerson) and Aaron Benward. His father is in the country duo Blue County, his mother is a part-time actress, model, and acting coach, and his grandfather is Contemporary Christian music artist Jeoffrey Benward. He has two younger sisters named Gracie and Ella.


title: Luke Benward

text: Benward's acting career started when he landed a role in the film "We Were Soldiers" as David Moore in 2002. His success grew in 2006, when he played Billy Forrester in the movie "How to Eat Fried Worms", which he won a Young Artist Award for in the category of Best Young Ensemble in a Feature Film.


title: Luke Benward

text: He also played 14-year-old Charlie Tuttle in the Disney Channel movie "Minutemen", the 14-year-old Alan in "Dear John", and the little boy who helps the abused girl in the music video "Concrete Angel" by Martina McBride. Benward's first album, "Let Your Love Out", came out on January 5, 2009, and contained five songs.


title: Luke Benward

text: He also toured with the Christian group "iShine LIVE" for a short time, where he would sing his music in concert. The record label that signed him is called In Crowd Productions, whose collective credits include Hilary Duff, India.Arie, the Backstreet Boys, Mat Kearney, Death Cab for Cutie, and the Jonas Brothers.


title: Luke Benward

text: He has also been in various commercials, including Nintendo, McDonald's, Willy Wonka, American Express, and Hamburger Helper. He also played the role of Nicky in "Mostly Ghostly" and played Stevie Dewberry in the film "Because of Winn-Dixie". He also played in the Disney Channel Original Movie "Girl vs. Monster" as Ryan Dean, the love interest of Skylar Lewis (Olivia Holt).


title: Luke Benward

text: Benward also had a recurring role as Matthew Pearson, the ex-boyfriend of Emily Hobbs (Ryan Newman) on "See Dad Run". He was in the movie "Cloud 9" from Disney Channel with "Liv and Maddie" star Dove Cameron and appeared as Beau, Teddy's love interest, on six episodes of "Good Luck Charlie", reuniting him with his "Minutemen" costar Jason Dolley. He appeared as Thor in the third-season premiere of the Disney Channel series "Girl Meets World".


title: Sassoon family

text: The Sassoon family, known as "Rothschilds of the East" due to the immense wealth they accumulated in finance and trade, are a family of Baghdadi Jewish descent. Originally based in Baghdad, Iraq, they later moved to Bombay, India, and then emigrated to China, England, and other countries.


title: Sassoon family

text: From the 18th century, the Sassoons were one of the wealthiest families in the world, with a corporate empire spanning the entire continent of Asia.


title: Sassoon family

text: The name of the family strongly implies a local, Mesopotamian origin. The family name of Sassoon is also commonly shared by many Armenian and Kurdish families and tribes who all originate from the mountainous district of Sason (whence the family and tribal names), west of Lake Van, in upper Mesopotamia in modern Turkey. It is, however, possible that some Spanish Sephardi blood was mixed with the primarily Mesopotamian Jewish Sasoons.


title: Sassoon family

text: Sassoon ben Salih (1750–1830) and his family were the chief treasurers to the pashas of Baghdad and Southern Iraq. His sons David (1792–1864) and Joseph Sassoon (1795–1872) fled from a new and unfriendly wāli. In 1828 David first went to the Persian Gulf port of Bushehr and in 1832 to Bombay, India, with his large family. In Bombay, he built the international business called David S. Sassoon, with the policy of staffing it with people brought from Baghdad. They filled the functions of the various branches of his business in India, Burma, Malaya, and east Asia. He cemented the family's dominant position in the Sino-Indian opium trade. The family's businesses in China, and Hong Kong especially, were built to capitalise on the opium business. His business extended to China – where Sassoon House (now the north wing of the Peace Hotel) on the Bund in Shanghai became a noted landmark – and then to England. In each branch, he maintained a rabbi. His wealth and munificence were proverbial; his philanthropy across Asia included the building of schools, orphanages, hospitals, and museums with the proceeds of the drug trade. On his death, tributes to him were made from across the continent by Muslims, Christians, Parsees, Jews, and Hindus. An important Jewish banker named Sassoon was hanged by the Ottoman Turks at the conclusion of the Siege of Kut al Amarah in April 1916. He may have been a member of this branch of the family or of Joseph Sassoon (vide infra).


title: Sassoon family

text: Joseph Sassoon went to Aleppo, Syria, where he established a merchant house and later his business interests spread to Alexandria, Thessaloniki, and Athens, which included a shipping company and a money exchange house. His five sons branched out in many directions: his son Moses Sassoon (1828–1909) returned to Baghdad before moving to Egypt where he built the financial house Joseph Sassoon & Sons, which later expanded and became an agent for Crédit Foncier in Egypt. In 1871 Moses' son Jacob Sassoon (1850–1936) was one of the largest cotton plantation owners in Egypt, and owned cotton mills; during the American civil war, his older brother Nissim (1840–1917) had made a fortune exporting Egyptian cotton to England making him Egypt's largest cotton exporter. In 1927, with Misr Bank and other Egyptian businessmen, Jacob Sassoon founded the Misr Spinning and Weaving Company (Arabic: شركة مصر للغزل والنسيج), also known as Misr Helwan or the El-Ghazl factory owning 61% of the company's shares. Jacob Sassoon also founded Egypt Crédit Foncier with Joseph Vita Mosseri, his grandson Eliau Joseph Sassoon was an architect, and designed the Assicurazioni Generali di Trieste Building. Eliau Sassoon was also a real estate investor and developer, who foresaw the unparalleled growth of Cairo and the lucrative effect such expansion would have on land values. It is not surprising, therefore, that many of the properties he invested in were located at the nexus of the elegant European quarter of Ismailia or in the choicest parts of Kasr al-Dubara, and later, in Garden City, Zamalek, and Giza. In 1952 his grandson Eliau (Elias) Nissim Eliau Joseph Sassoon (1928–2010) founded Banque du Caire with Maurice Joseph Cattaui (1925–2009).


title: Sassoon family

text: Eliau (Elias) Nissim Eliau Joseph Sassoon (Hebrew: אליהו נסים אליאו יוסף ששון) (1928-2010), (always called Elias), born in Aleppo, Syria, to Nassim Eliau Sassoon (1911–1988) a wealthy merchant, banker, and former partner at Safra Freres a bank based in Aleppo, and Messouda Sassoon (born Shamash) (1911–1992).


title: Sassoon family

text: Elias Sassoon was Joseph Sassoon's most influential and wealthiest descendant, in 1940 he was sent to Alexandria to attend the prestigious boarding school, Victoria College. He later joined his family's business in 1946 where he worked for the family's business in Egypt.


title: Sassoon family

text: Among the many holdings, the family had at the time included interests in Burmah Oil, Turkish Petroleum Company and the Anglo-Iranian Oil Company, a textile factory, a large cotton export business and interests in both the General Company of Commerce and Industry of Greece (later Attica Enterprises Holding S.A.) and Atlas Maritime.


title: Sassoon family

text: In 1947 Elias focused his attention on three primary sectors: the newly booming oil exploration industry sweeping the Middle East, shipping and banking. With a £5,000 loan from his father, Elias invested in Standard Oil adding to his family's existing holdings in the company. That same year he married Hannah Rochel Jacque Sassoon (née de Menasche) (1929–2009), granddaughter of Baron Jacques Bohor Yacoub Levi de Menashe (d.1916).


title: Sassoon family

text: His great-grandfather, David Solomon Sassoon (1871–1956) had been an investor in Socony-Vacuum Oil Company, which later partnered with Standard Oil to provide markets for the oil reserves in the Middle East. In 1906, Socony (later Mobil) opened its first fuel terminals in Alexandria with financing provided by David Solomon Sassoon. Elias Sassoon was a devoted Zionist and considered the British anything but friends to the Jewish people because of their blockade in the Mediterranean to refugee vessels carrying Jewish refugees fleeing the horrors of World War II, and although to a lesser extent, he considered the British government as culpable nonetheless in the atrocities against world Jewry.


title: Sassoon family

text: In 1952 he cofounded Banque du Caire with his childhood friend Moise Joseph Maurice Cattaui (1925–2009). By then Elias Sassoon had expanded his family's business to France, Brazil, South Africa and the United States where the family exported cotton to and had maintained trading posts since the 1800s.


title: Sassoon family

text: The Sassoons believed that Mesopotamia (now Syria and Iraq) contained substantial reservoirs of oil, the forerunner of the Iraq Petroleum Company (IPC) the Turkish Petroleum Company (TPC). David Solomon Sassoon was among the first to secure the interest of the Imperial German banks and companies, already involved in the building of the Berlin–Baghdad railway, which he played an active role in its financing. This German interest was followed by British interests when David Sassoon became an agent for the Rothschilds in Ottoman Empire. In 1911, in an attempt to bring together British and German interests competing in the region, Sassoon formed a consortium of British investors composed of banks and companies and formed the African and Eastern Concession Ltd.


title: Sassoon family

text: In 1953 Elias Sassoon used these networks of interests to expand his family's investment interests to include mining concessions in Africa. In 1957 the new Egyptian post-revolution government under Nasser nationalized all European particularly British and French companies and banks. The government also began expelling foreigners and the Jewish community of Egypt once again, despite its many contributions to the country's artistic, economic, political, and academic fields found itself under the government's harassment and intimidation, many were forced to leave the country with no more than one suitcase and most had their assets and properties seized by the Revolutionary Council.


title: Sassoon family

text: The Sassoons were among those, whose assets were confiscated and in 1966 Elias Sassoon and his wife were taken to the port in Alexandria and expelled from the country. Elias’ wife who was an Egyptian citizen was declared non-citizen, and at the request of the Egyptian government, Elias's Syrian citizenship was revoked. They were given laissez-passer (travel documents) and ordered aboard a ship bound for Greece, however, their son Edouard Elias Sassoon (1948–1985) who was a medical student at the University of Alexandria was denied an exit visa.


title: Sassoon family

text: The government accused Elias Sassoon of using his family's banking network to help smuggle assets belonging to members of the Jewish community out of the country and demanded that he return his assets held in Europe before his son is allowed to leave. After paying what amounted to ransom money, totaling £4 million and the intervention of both the French and the Greek governments, Edouard Sassoon joined his family in 1971, with his wife Josephine Celine Esther (née Cattaui) (1949–1994), daughter of Moise Cattaui who was also denied exit visa after her family was expelled from the country in 1964.


title: Sassoon family

text: Elias Sassoon had established Sassoon Cattaui Investment Holding (later Providence Group), a privately owned family hedge fund with Moise Cattaui in 1961 in Switzerland with assets from the Sassoon Family Trust, which had been formed in Lausanne, Switzerland in 1910. In 1970, the partners moved the company Curaçao (Netherlands Antilles) a private family investment group, which is not required to register with the SEC or comply with reporting requirements under the Dodd–Frank, reform act. It is said that at the time of the formation of the Fund, the total value of assets under management in 1961 was £25million.


title: Sassoon family

text: The Fund invested in commercial real estate properties in the U.S., Canada, and Greece as well as in precious metals, oil & gas, and securities. The fund also speculated in the currency markets, among its many holdings are: BHP, the co-investor in Le Méridien hotel company with Air France, American Express, General Motors, Wells Fargo, HSBC, Lehman Brothers, ExxonMobil, Conoco Phillips, Fendi, Giorgio Armani, Microsoft, Sun Microsystems, Midland Bank, stockbroking firm Frankel Pollak (which was later sold to Sasfin Bank, a Sassoon family bank based in South Africa) and S&P Global. It is rumoured that at the time of Elias Sassoon's death, the Fund, which is not required to file its financials with the SEC had over $100 billion of assets under management, most of which are assets of both the Sassoon and Cattaui families.


title: Sassoon family

text: Sassoon's eight sons also branched out in many directions. The Sassoon family was heavily involved in the shipping and opium production industry in China and India. Elias David (1820–1880), his son by his first wife, had been the first of the sons to go to China, in 1844. He later returned to Bombay, before leaving the firm to establish E.D. Sassoon & Co. in 1867, with offices in Bombay and Shanghai. Another son, Albert Abdullah David Sassoon (1818–1896) took on the running of the firm on his father's death, and notably constructed the Sassoon Docks, the first wet dock built in western India. With two of his brothers he later became prominent in England, and the family were friends of the Prince of Wales, later King Edward VII. One daughter of the family, Rachel Sassoon Beer, joined her husband in running a number of British newspapers, including "The Sunday Times" (1893–1904) and "The Observer", which she also edited.


title: Sassoon family

text: Of those who settled in England, Sir Edward Albert Sassoon (1856–1912), the son of Albert, married Aline Caroline de Rothschild, and was a Conservative member of Parliament from 1899 until his death. The seat was then inherited by his son Sir Philip Sassoon (1888–1939) from 1912 until his death. Philip served in the First World War as military secretary to Field Marshal Sir Douglas Haig and, during the 1920s and 1930s, as Britain's undersecretary of state for air. The twentieth-century English poet, one of the best known World War I poets, Siegfried Sassoon (1886–1967) was David's great-grandson.


title: Sassoon family

text: Another descendant of David Sassoon is the British banker and former Treasury's commercial secretary James Meyer Sassoon. He was mentioned in the Paradise Papers as one of the beneficiaries of a tax-exempt Cayman Island trust fund worth $236 million in 2007 and defended it as being of non-UK origin.


title: Sassoon family

text: The branch which carried on the rabbinical tradition has been represented by Rabbi Solomon David Sassoon (1915–1985), who moved from Letchworth to London and then to Jerusalem in 1970. He was the son of one David Solomon Sassoon (1880–1942) who collected Jewish books and manuscripts and catalogued them in two volumes.


title: Sassoon family

text: The bulk of this collection is stored at the British Library in London, England. Some examples of this collection are maintained at the University of Toronto Library in Toronto, Canada. None of these priceless works are presently stored in the United States.


title: Sassoon family

text: David Sassoon was the son of Flora Abraham, who had moved from India to England in 1901 and established a famous salon in her London home. Solomon Sassoon had two sons, Isaac S. D. Sassoon and David Solomon Sassoon, who are both rabbis.


title: Sex hormone

text: Sex hormones, also known as sex steroids, gonadocorticoids and gonadal steroids, are steroid hormones that interact with vertebrate steroid hormone receptors. The sex hormones include the androgens, estrogens, and progestogens. Their effects are mediated by slow genomic mechanisms through nuclear receptors as well as by fast nongenomic mechanisms through membrane-associated receptors and signaling cascades. The polypeptide hormones luteinizing hormone, follicle-stimulating hormone and gonadotropin-releasing hormone – each associated with the gonadotropin axis – are usually not regarded as sex hormones, although they play major sex-related roles.


title: Sex hormone

text: Natural sex hormones are made by the gonads (ovaries or testes), by adrenal glands, or by conversion from other sex steroids in other tissue such as liver or fat.


title: Sex hormone

text: In many contexts, the two main classes of sex hormones are androgens and estrogens, of which the most important human derivatives are testosterone and estradiol, respectively. Other contexts will include progestogens as a third class of sex steroids, distinct from androgens and estrogens. Progesterone is the most important and only naturally occurring human progestogen. In general, androgens are considered "male sex hormones", since they have masculinizing effects, while estrogens and progestogens are considered "female sex hormones" although all types are present in each sex at different levels.


title: Sex hormone

text: There are also many synthetic sex steroids. Synthetic androgens are often referred to as anabolic steroids. Synthetic estrogens and progestins are used in methods of hormonal contraception. Ethinylestradiol is a semi-synthetic estrogen. Specific compounds that have partial agonist activity for steroid receptors, and therefore act in part like natural steroid hormones, are in use in medical conditions that require treatment with steroid in one cell type, but where systemic effects of the particular steroid in the entire organism are only desirable within certain limits.


title: UTC offset

text: The UTC offset is the difference in hours and minutes between Coordinated Universal Time (UTC) and local solar time, at a particular place. This difference is expressed with respect to UTC and is generally shown in the format , , or . So if the time being described is two hours ahead of UTC (such as in Kigali, Rwanda [approx. 30° E]), the UTC offset would be "+02:00", "+0200", or simply "+02".


title: UTC offset

text: By convention, every inhabited place in the world has a UTC offset that is a multiple of 15 minutes but the majority of offsets are stated in whole hours. There are many cases where the national standard time uses a time zone that differs from the UTC offset appropriate to its longitude.


title: UTC offset

text: A "time zone" is a geographical region in which residents observe the same standard time. Although nominally a new time zone is established every 15 degrees east or west of the prime meridian (meaning a one hour change in solar time), in practice local geographical or political considerations may vary its application. The most extreme example of this is time in China, which applies a single standard time offset of (eight hours ahead of Coordinated Universal Time), even though China spans five geographical time zones.


title: UTC offset

text: The UTC offset (or time offset) is an amount of time subtracted from or added to Coordinated Universal Time (UTC) time to specify the local solar time (which may not be the current civil time, whether it is standard time or daylight saving time).


title: UTC offset

text: Several regions of the world use daylight saving time (DST) and the UTC offset during this season is typically obtained by adding one hour to local standard time. Central European Time is replaced by Central European Summer Time , and Pacific Standard Time is replaced by Pacific Daylight Time .


title: Murrieta, California

text: Murrieta is a city in southwestern Riverside County, California, United States. The population of Murrieta was 110,949 as of the 2020 census. Murrieta experienced a 133.7% population increase between 2000 and 2010, making Murrieta one of the fastest-growing cities in the state during that period. Largely residential in character, Murrieta is typically characterized as a bedroom community. Murrieta is bordered by the city of Temecula to the south, the cities of Menifee and Wildomar to the north, and the unincorporated community of French Valley to the east. Murrieta is located in the center of the Los Angeles-San Diego mega-region. Murrieta is named for Juan Murrieta, a Californio ranchero who founded the town.


title: Murrieta, California

text: For most of its history, Murrieta was not heavily populated. On June 9, 1873, Domingo Pujol, Francisco Sanjurjo, and Juan and Ezequiel Murrieta purchased the Rancho Pauba and Rancho Temecula Mexican land grants, comprising in the area. Ezequiel returned to Spain and turned the land over to his younger brother, Juan Murrieta (1844–1936), who brought 7,000 sheep to the valley in 1873, using the meadows to feed his sheep. The partnership dissolved in 1876 and Ezequiel and Juan Murrieta retained 15,000 acres of the northern half of the Temecula Rancho. Ezequiel and Juan Murrieta granted a right-of-way, one hundred feet wide to the California Southern Railroad through the Temecula Rancho on April 28, 1882 so that the railroad could be constructed through the valley.


title: Murrieta, California

text: In 1884, the Temecula Land and Water Company purchased about 14,500 acres from Juan Murrieta and mapped a townsite along the California Southern Railroad. Others discovered the valley after the construction of a depot in 1887 that connected Murrieta to the Southern California Railroad's transcontinental route. By 1890, some 800 people lived in Murrieta. Today much of the site (about 50 acres) is home to a Bible college and conference center, owned by Calvary Chapel Costa Mesa, which has invested millions of dollars into restoring and rebuilding the old resort rooms. When the trains stopped in 1935, tourists—the lifeblood of the town—were much harder to come by. The boom that Murrieta had experienced due to the train and the hot springs gradually died, leaving Murrieta as a small country town.


title: Murrieta, California

text: Although US Route 395 passed through Murrieta, it was not until Interstate 15 was built in the early 1980s that another boom began to take hold. By the late 1980s, suburban neighborhoods were being constructed, and people began moving to the Murrieta area from cities and towns in San Diego and Orange Counties, as well as other parts of Riverside County.


title: Murrieta, California

text: In 1990, residents began a campaign for city status which resulted in the incorporation of the City of Murrieta on July 1, 1991. By then the population was 24,000, a major increase from 2,200 in 1980. Between 1991 and 2007, the city's population further increased to an estimated 97,257 residents, and the city's population was 103,466, making it the largest city in southwestern Riverside County at that time.


title: Murrieta, California

text: In July 2014, Murrieta garnered national attention following days of citizen protests of detained immigrants.


title: Murrieta, California

text: Murrieta residents successfully blocked busloads of illegal immigrant detainees. They were en route to a temporary relocation and detention facility, which the federal government had planned to establish in the town.


title: Murrieta, California

text: According to the United States Census Bureau, the city has a total area of , of which 99.89% of it is land and 0.11% is covered by water. Murrieta Creek runs southeasterly through the Murrieta Valley.


title: Murrieta, California

text: Murrieta has a Mediterranean climate or dry-summer subtropical (Köppen climate classification "Csa"). Murrieta has an average of 263 sunshine days and 35 days with measurable precipitation annually. April through November is warm to hot and dry with average high temperatures of and lows of . The period of November through March is somewhat rainy. The city is also subject to the phenomenon typical of a microclimate: temperatures can vary as much as between inland areas and the coast, with a temperature gradient over 1 °F per mile (0.3 °C/km) from the coast inland. Murrieta gets on average 31 days a year of some type of precipitation. Murrieta averages of precipitation annually, which mainly occurs during the winter and spring (November through April) with generally light rain showers, but sometimes heavy rainfall and thunderstorms. Snowfall is rare in the city basin, but nearby mountains slopes typically receive snowfall each winter.


title: Murrieta, California

text: The 2010 United States Census reported that Murrieta had a population of 103,466. The population density was . The racial makeup of Murrieta was 72,137 (69.7%) White (55.7% non-Hispanic White), 5,601 (5.4%) African American, 741 (0.7%) Native American, 9,556 (9.2%) Asian, 391 (0.4%) Pacific Islander, 8,695 (8.4%) from other races, and 6,345 (6.1%) from two or more races. Hispanics or Latinos of any race were 26,792 persons (25.9%). The census reported 103,037 people (99.6% of the population) lived in households, 291 people (0.3%) lived in noninstitutionalized group quarters, and 138 people (0.1%) were institutionalized.


title: Murrieta, California

text: Of the 32,749 households, 48.4% had children under the age of 18 living in them, 62.8% were opposite-sex married couples living together, 3,814 (11.6%) had a female householder with no husband present, and 1,642 (5.0%) had a male householder with no wife present, with 1,626 (5.0%) unmarried opposite-sex partnerships and 192 (0.6%) same-sex married couples or partnerships. About 5,208 households (15.9%) were made up of individuals, and 2,248 (6.9%) had someone living alone who was 65 years of age or older. The average household size was 3.15. There were 26,033 families (79.5% of all households); the average family size was 3.51.


title: Murrieta, California

text: The population was distributed as 31,471 people (30.4%) under the age of 18, 9,891 people (9.6%) aged 18 to 24, 28,144 people (27.2%) aged 25 to 44, 23,555 people (22.8%) aged 45 to 64, and 10,405 people (10.1%) who were 65 years of age or older. The median age was 33.4 years. For every 100 females, there were 95.2 males. For every 100 females age 18 and over, there were 91.2 males.


title: Murrieta, California

text: The 35,294 housing units averaged 1,050.0 per square mile (405.4/km), of which 23,110 (70.6%) were owner-occupied and 9,639 (29.4%) were occupied by renters. The homeowner vacancy rate was 3.1%; the rental vacancy rate was 7.8%; 73,518 people (71.1% of the population) lived in owner-occupied housing units and 29,519 people (28.5%) lived in rental housing units.


title: Murrieta, California

text: As of the census of 2000, 44,282 people, 14,320 households, and 11,699 families resided in the city. The population density was . The 14,921 housing units averaged 525.6 per square mile (202.9/km). The racial makeup of the city was 81.6% White, 3.4% African American, 0.7% Native American, 4.0% Asian, 6.0% from other races, and 4.3% from two or more races. Hispanics or Latinos of any race were 17.5% of the population.


title: Murrieta, California

text: Of the 14,320 households, 47.5% had children under the age of 18 living with them, 70.2% were married couples living together, 8.1% had a female householder with no husband present, and 18.3% were not families. About 14.5% of all households were made up of individuals, and 6.7% had someone living alone who was 65 years of age or older. The average household size was 3.1 and the average family size was 3.4; 33.7% of the population of the city was under the age of 18, 6.4% were from 18 to 24, 30.8% were from 25 to 44, 17.6% were from 45 to 64, and 11.4% were 65 years of age or older. The median age was 34 years. For every 100 females, there were 96.1 males. For every 100 females age 18 and over, there were 92.7 males.


title: Murrieta, California

text: According to a 2007 estimate, the median income for a household in the city was $78,883, and the median income for a family was $90,930. Men had a median income of $49,107 versus $32,468 for women. The per capita income for the city was $23,290. About 3.0% of families and 4.3% of the population were below the poverty line, including 4.3% of those under age 18 and 5.4% of those age 65 or over.


title: Murrieta, California

text: Murrieta was the safest city in Riverside County in 2012, and in 2009, Murrieta was listed as the second-safest city (over 100,000 in population) in the United States, behind Irvine, California.


title: Murrieta, California

text: According to the city's 2021 Comprehensive Annual Financial Report, the top non-military employers in the city are:


title: Murrieta, California

text: The Town Square is the location of the Murrieta Police Department, Murrieta Public Library, City Hall, a senior center, and $2 million veterans memorial.


title: Murrieta, California

text: Bear Creek Golf and Country Club was designed by Jack Nicklaus, and Presidents Ronald Reagan and Gerald Ford have played there. The Golf Club at Rancho California was designed by Robert Trent Jones, Sr.


title: Murrieta, California

text: In the United States House of Representatives, Murrieta is in . In the United States Senate, California is represented by Democrats Dianne Feinstein and Alex Padilla.