Free Essays on There Are No Children Here

There are no Children Here Alex Kotlowitz's book, There are no Children Here, deals with the subject of race, values, and community responsibility of the urban underclass. The American inner city deals with the issues such as violent crime and drug wars. With these two explosive issues, the neighborhood experiences the downward spiral of social separation, unemployment and welfare dependence. The lives of two black boys, Lafayette, 10 and Pharaoh, 7 are followed as they struggle to grow up in one of Chicago's worst housing projects. Lafayette and Pharaoh are not any different than many of their neighbors. Their mother is welfare dependent. Their father is an alcoholic and drug abuser. In the home, there are other siblings, an older brother and sister along with younger triplets, just like so many other families in the area. Kotlowitz takes you into an offensively maintained housing project infested with gangs, where murders and shootings are an everyday thing. The image of the devastation and the despair of no hope of the people living inside the project are vivid. One can truly sense the hopefulness, grasping the loss of family and ardently desire a new life for the boys. You hold out hope that things will work out for the boys. In America's minefield of urban life, Lafayette and Pharaoh are surrounded by violence and poverty through their lives. The neighborhood had no banks, no public libraries, no movie theatres, no skating rinks, or bowling allies. The lack of respectable businesses only contributes to the demise of the neighborhood and unemployment in the area. With the drug lords keeping shop in an abandoned building, drug abuse is rampant and shooting is common. There were no drug rehabilitation programs or centers to help combat the problem. Police feared going into the ghetto for their own safety. There are no Children Here embraces Lafayette and Pharaoh over a two-year period in which they struggle with school, attemp... Free Essays on There Are No Children Here Free Essays on There Are No Children Here The subject matter of the book shows the conditions of poor people in the subsidized housing projects of Chicago, Illinois. The Riverses are members of a poor family. The family lives in Henry Horner Homes, a subsidized housing project in Chicago. The family relies on welfare and federal assistance for support. They cannot afford most luxuries and many necessities; therefore, life is an ongoing struggle to survive. Many adults and children reside in the family's household. These extra family members further strain the family's resources and cramp their living room in the family's apartment. LaJoe has eight children, all living in the apartment: LaShawn, Weasel, Terence, Lafayette, Pharoah, Tammie, Tiffany, and Timothy. LaShawn has three children: one of which is named DeShawn. Terence has three children also: one of which is nicknamed "Snuggles." Paul, LaJoe's ex-husband, stays with the family on occasion. Leila Mae, LaJoe's mother, sometimes stays with the family. Gangs control the buildings in the projects. Gang members hire residents of the buildings to store weapons and drugs in their apartments. Gang members sell drugs in the neighborhoods and attempt to obtain help selling drugs from small children. Some gangs break into apartments to steal from them and use them as safe havens against the police and other law enforcement agencies. Gangs have "turf wars" which result in gun battles which injure and kill many people, most of which are innocent bystanders. The buildings of the Chicago Housing Authority are in disrepair and mismanaged. The employees at the Chicago Housing Authority embezzle money from the budget. A review finds several employees guilty and they are fired. The buildings of the Chicago Housing Authority are in disrepair. Rusted appliances litter the basements. The heating coils in the buildings' furnaces are missing. The buildings have not been painted in many years. Some buildings have numerous bloodstains in them fro... Free Essays on There Are No Children Here There are no Children Here Alex Kotlowitz's book, There are no Children Here, deals with the subject of race, values, and community responsibility of the urban underclass. The American inner city deals with the issues such as violent crime and drug wars. With these two explosive issues, the neighborhood experiences the downward spiral of social separation, unemployment and welfare dependence. The lives of two black boys, Lafayette, 10 and Pharaoh, 7 are followed as they struggle to grow up in one of Chicago's worst housing projects. Lafayette and Pharaoh are not any different than many of their neighbors. Their mother is welfare dependent. Their father is an alcoholic and drug abuser. In the home, there are other siblings, an older brother and sister along with younger triplets, just like so many other families in the area. Kotlowitz takes you into an offensively maintained housing project infested with gangs, where murders and shootings are an everyday thing. The image of the devastation and the despair of no hope of the people living inside the project are vivid. One can truly sense the hopefulness, grasping the loss of family and ardently desire a new life for the boys. You hold out hope that things will work out for the boys. In America's minefield of urban life, Lafayette and Pharaoh are surrounded by violence and poverty through their lives. The neighborhood had no banks, no public libraries, no movie theatres, no skating rinks, or bowling allies. The lack of respectable businesses only contributes to the demise of the neighborhood and unemployment in the area. With the drug lords keeping shop in an abandoned building, drug abuse is rampant and shooting is common. There were no drug rehabilitation programs or centers to help combat the problem. Police feared going into the ghetto for their own safety. There are no Children Here embraces Lafayette and Pharaoh over a two-year period in which they struggle with school, attemp... Free Essays on There Are No Children Here As we are often clouded by our optimistic views of society and equality, we tend to assume that every child has an equal chance at growing up and achieving their own â€Å"American Dream.† We would all like to believe that children are growing up in equal environments that allow them to develop and succeed in life. However, these optimistic views are not at all realistic. Though we want to see equal opportunities for every child, the stark truth about poverty stricken housing projects is a matter that certainly exists. The idea of fairness we have made up in our minds is not often the case, and through Alex Kotlowitz’s There Are No Children Here, our eyes are opened to many of the harsh situations such as poverty, gangs, racism, and violence that children are forced to grow up in. Alex Kotlowitz attempts to expose the truths of poverty, race, and children throughout his literary works. He is widely known for his concerns for urban affairs and social issues in his writings in The Wall Street Journal. Kotlowitz grew up in New York City and worked as a community organizer in Atlanta in the mid-70’s. He graduated from Wesleyan University in Middletown, Connecticut where he received two degrees. Before the start of his career with The Wall Street Journal he worked as a freelance journalist, contributing to â€Å"The MacNeil-Lebrer Newshour,† National Public Radio, and numerous magazines. In 1985 he was approached to write an essay for a Chicago magazine on the subject of children living in poverty. His first book, There Are No Children Here, came about from a series of articles he wrote for The Wall Street Journal. This book has received a number of awards including the Helen B. Bernstein Award for Excellence in Journalism, the Carl Sandburg A ward and a Christopher Award. His ability to accurately portray the children of the Chicago projects while still informing the reader’s heart has been recognized by many and earned the...

Behavioural Perspectives of Mental Health

Question 1: Describe what is meant by a â€Å"behavioural perspective† of mental health and illness. Use examples from the literature to show how medical and behaviourally-based approaches differ. Behavioural perspectives concerning mental health and illness include bio medical and psychological approaches. Bio medical approaches incorporate pharmacological treatments, heritability, criterion – based diagnosis, and the ability to examine structures and functions of the brain. Psychological approaches comprise psychoanalytical, cognitive, non directive psychotherapy, and behavioural analysis.When making a behavioural perspective concerning a client’s mental health and illness it is important to â€Å"distinguish how problems are conceptualised, what is important to target for change, the process of behaviour and how to change the behaviour† (M. Burkhardt, personal communication, 2010). To distinguish how a behaviour is caused physicians need to examine the behaviour and consider the clients environmental antecendents and consequences concerning their behaviour (M. Burkhardt, personal communication, 2010).Behavioural perspectives concerning mental health and illness have changed over time and continually vary in regards to people’s thoughts, point of views, theories and studies. There are many psychological and biological theories and studies that can impact on the treatment decision, conflicting between psychological and pharmacological treatments (M. Burkhardt, personal communication, 2010). The choice of treatment can depend greatly on the client and physicians views and beliefs. Medical approaches are an important and popular intervention for many people who have been diagnosed with a mental health problem. There are many studies and research surrounding mental health and illness in regards to the medical approach of treatment, evidence in support of the medical approach and biological causation generally falls into two categories, family studies and brain structure/ function studies (Wyatt, 2009). Through the use of functional imaging scans researchers have found that there are differences in the activities of the brains with a range of psychiatric illnesses (Leach, 2009).Frith and Johnstone (2003) as cited in Leach (2009) suggest that â€Å"People diagnosed with schizophrenia have noticeable differences in certain aspects of their brain structures compared to others without that diagnosis†. Genetic factors have been linked to making a contribution to mental illnesses, â€Å"both depression and schizophrenia have been linked to differences in brain chemistry, and researches have suggested genetic patterns of inheritance for these conditions† (Leach, 2009).Studies have found that there are â€Å"biological differences to those who are and are not prone to depression, confirmed by the fact that drugs that have no effect on mood in normal people relieve depression in those who are ill, and the observation that a depressed mood can be precipitated in people who are prone to depressive illnesses simply by manipulating the tryptophan content in their diet† (Delgado et al, 1990 as cited in Kendell, 2009). Many clients who seek help for mental illnesses desire medications due to the fact that they are convinced that their illness are caused biochemically or genetically (Wyatt, 2009). Mental illnesses can be explained in many cases to be cause from a ‘chemical imbalance’ within the body, the medical approach to treat these chemical imbalances is through the use of pharmacological and psychotropic medications to improve their condition by re-balancing chemicals within their body. Behaviourally based approaches involving mental health and illness, consist of non-medical approaches studying client’s behaviours and thoughts, why they exist and what they can cause, also discussing and creating alternative measures to overcome these thoughts and behaviours.Behavioural analysis focuses on behaviours a client presents with and the relationship these behaviours have with the environment, by analysing these relationships, scientific principles of behavioural analysis can contribute to helping people change the way they think, feel and behave. Client’s behaviours are a response to particular circumstances and through the use of behavioural therapy these responses can be modified, changing harmful and unhelpful behaviours that the client may have.Behavioural treatment approaches explores the client’s present situation, considering where their distressing thoughts, feelings and behaviours come from, what reinforces them and how they can be changes (Leach, 2009). When examining a mental illness through the use of the behavioural analytical approach the first step is to have an insight of what the client say’s and does to themselves and others, if the client has severe depression and is participating in self injuries behaviours then it is important to find out what these behaviours are.To recognise and solve these behaviours there needs to be an understanding of the client’s physical condition, setting and environment and the events occurring prior and accompanying these behaviours, such as when the client is in a depressive state having feelings that they ‘don’t want to live’ or ‘fe el like this anymore’, that is when they perform these behaviours such as cutting their wrists, this needs to be established by the physician before interventions can be designed. To achieve positive results by decreasing and diminishing these behaviours their need to be consistency with the interventions and scientific methods.Another non-medical approach structured around behaviour is cognitive behavioural therapy, â€Å"the basic premise of this approach it that an individual’s appraisal of personal life events largely determines how she or he feels and behaves† (Leach, 2009). The key purpose of behavioural approaches is to help client’s understand their behaviours, beliefs and thoughts and how they can used interventions and scientific methods to overcome these issues. It is evident that the medical and behavioural aspects concerning mental health and illness differ greatly in the two separate approaches.Medical based approaches are centred around heritability, genetic factors, examining client’s brain structures and functions, and stabilising ‘chemical imbalances’ through the use of pharmacological and psychotropi c medications. In contrast the behavioural approach looks into the client’s thoughts, beliefs and behaviours, the relationship between behaviours and environment are considered, and once the cause and effects of the behaviours are established interventions and scientific methods are put into place to decrease and diminish these behaviours.

Language development Essay Example | Topics and Well Written Essays - 250 words - 1

Language development - Essay Example In all of these aspects of language acquisition, language imbalance should be considered when gauging the extent and ability of child in the process of learning a second language. Language imbalance is brought about by a conflict between two or more languages that a child is exposed to in the development process (Hoff, 2009). Influences on vocabulary are characterized by a myriad of factors in a child’s life both at school and at home. Vocabulary development is influenced by language socialization that takes two general styles of child-rising that are child-centered and situation centered. In child centered approach, adults use two strategies of self-lowering through baby talk and child rising by interpreting unintelligible gibberish(Barrett, 1999). The situation-centered approach does not require adults to simplify their language, but children are expected to learn, understand and produce adult like speech mannerism. The culture surrounding a child has a significant influence on the development of language in a child because it influences the development of their identity. Cultural influencers, in society, determine the personality and identity that a child forges for self in line with what the societal norms dictate (Barrett, 1999). Young English language learners should be encouraged by their educators, caregivers and parents to achieve a more rounded language development process. Teachers need to be good models of language use and encourage learners to interact with other children as much as possible (Hoff, 2009). This is aimed at reinforcing their vocabulary repertoire. Second language learners can be exposed to meaningful learning activities that encourage them to practice their new language

Viruses vs. Windows Essay Example | Topics and Well Written Essays - 250 words - 3

Viruses vs. Windows - Essay Example I would also turn on the windows update option in order to receive security updates for his/her windows. I would recommend my neighbor to install an antivirus application and update it on a regular basis. I would not recommend him/her to use a free version of the above-mentioned antivirus applications because they are sometimes unable to deal with dangerous viruses. Licensed applications provide reliable security to the files stored in any machine. I would recommend my neighbor to use Avast antivirus application because it has eight effective real-time shields that protect the system from viruses, as well as consumes fewer system resources as compared to other antivirus applications. My last recommendation for him/her would be to avoid opening junk emails and suspicious internet links because they are likely to contain viruses. Both of these antivirus applications run very well on the Windows XP. I would also turn on the windows update option in order to receive security updates for his/her windows. I would recommend my neighbor to install an antivirus application and update it on a regular basis. I would not recommend him/her to use a free version of the above-mentioned antivirus applications because they are sometimes unable to deal with dangerous viruses. Licensed applications provide reliable security to the files stored in any machine.

A Nuclear Reactor :: science

A Nuclear Reactor The term Nuclear Reactor means an interaction between two or more Nuclei, Nuclear Particles, or Radiation, possibly causing transformation of the nuclear type; includes, for example, fission, capture, elastic container. Reactor means the core and its immediate container. Nuclear Reactors are used to produce electricity . The numbers of Nuclear Reactor plants have grown sufficiently . Electricity is being generated in a number of ways, it can be generated by using Thermal Power. It can be employed by using two basic systems a Steam Supply System and an Electricity Generating System these two systems are related to each other. The Steam Supply System produces steam from boiling water by the burning of coals and the Electricity Generating System produces electricity by steam turning turbines. The Nuclear power plants of this century depend on a particular type of Nuclear Reaction, Fission (The splitting of a heavy nucleus like the uranium atom to form two lighter "fission ! fragments" a s well as less massive particles as the Neutrons). In the Nuclear Reactors this splitting is induced by the interaction of a neutron with a fissionable nucleus. Under suitable conditions, a "chain" reaction of fission in which events may be sustained. The energy released from the fission reactions provide heat, part of which is ultimately converted into electricity. In the present day Nuclear power plants, this heat is removed from the Nuclear fuel by water that is pumped past rods containing fuel. The basic feature of the nuclear reactor is the release of a large amount of energy from each fission event that occurs in the nuclear reactors core. On the average, a fission event releases about 200 million electron volts of energy. a typical chemical reaction, on the other hand releases about one electron volt. The difference, roughly a factor of 100 million electron volts. The complete fission of one pound of uranium would release roughly the same amount of energy as the combination o f 6000 barrels of oil or 1000 tons of high quality oil. The reactor cooling fluid serves a dual purpose. Its most urgent function is to remove from the core the heat that results when the energy released from the Nuclear reactions is transformed by the collisions into the random nuclear motion. An associated function is to transfer this heat into an outside core, typically for the production of electricity. The designer provides for a nuclear core in a container through which a cooling fluid is pumped.

Assignment Solution 01

North South University ETE 321 – Spring 2010 Instructor: Nahid Rahman Assignment #1 Total Marks: 100 Worth: 7. 5% 1. Consider the sinusoidally modulated DSB LC signal shown below. The carrier DSB-LC frequency is ? c and the message signal frequency is ? m. (a) Determine the modulation index m. Solution: Amax = 25 Amin = 5 ? 25 ? 5 = = 0. 67 + 25 + 5 (b) Write an expression for the modulated signal ? (t). Solution: 1 1 ) = (25 ? 5) = 10 = ( ? 2 2 1 1 ) = (25 + 5) = 15 = ( + 2 2 = + cos = cos + ( ) cos Assignment 1 Sol Page: 1 of 12 = 15 cos + 10 cos cos (c) Derive time domain expressions for the upper and lower sidebands.Solution: = 15 cos + 10 cos cos = 15 cos + 5 cos( + ) + 5 cos( ? ) Upper sideband: 5 cos( + ) ) Lower sideband: 5 cos( ? (d) Determine the total average power of the modulated signal , the carrier power and the two sidebands. Solution: Power of carrier signal = (15 cos )2 = + ? (15)2 2 cos cos = (cos( + ) + cos( ? )) 2 1 = 112. 5 W 2 (5)2 2 (5)2 Power of upper sideband = (5 cos( Power of lower sideband = (5 cos( ))2 = = 12. 5 W = 12. 5 W Power of modulated signal = 137. 5 W (e) Assuming that the message signal is a voltage signal, calculate the PEP (Peak Envelop Power) across a 100? load. Solution: PEP = 2 ))2 = eed to obtain the RMS value by dividing the peak by v2. (f) Determine the modulation efficiency ?. Solution: 12. 5 + 12. 5 = = 18. 18% 137. 5 Amax is the peak value of the modulated signal. To calculate the DC power, we = ( )2 v2 = (25 )2 v2 100 = 3. 125 W Assignment 1 Sol Page: 2 of 12 2. A DSB-SC modulated signal can be generated by multiplying the message signal with a periodic pulse generator and passing the resultant signal through a band-pass filter. = 2 cos 200 + cos 600 ( )= 1 2 + 2 ? (? 1) ? 1 cos ( =1 2 ? 1 (2 ? 1)) (a) Find the DSB-SC signal component in V(t). Solution: Input to the BPF: = ? 1 1 2 ? (? ) = ( ){ + cos ( (2 ? 1))} =1 2 ? 1 2 1 2 2 ? 1 2 1 = ( ) { + cos + †¢ cos 3 + †¢ cos 5 + other terms} 2 3 5 1 2 2 2 ( )+ ( ) cos ( ) cos 3 ( ) cos 5 = ? + + other terms 2 3 5 Output of the BPF: 2 = cos 2 = 2 cos 200 + cos 600 cos (b) Specify the unwanted components in V(t) that need to be removed by a BPF of suitable design. Solution: 1 2 2 ( ), ( ) cos 3 ( ) cos 5 , ,other terms 2 3 5 (c) Assume the carrier frequency is 500 Hz. Sketch the spectral density of the resulting DSB-SC waveform. Solution: = 2 cos 200 + cos 600 =2 ? 200 + 2 + 200 + ? 600 + + 600 Assignment 1 Sol Page: 3 of 12 = 2 = 1 cos ? = 2 1 = 2 ? 00 rad = 1000 rad See plot below. (d) In the sketch for Part (c), specify lower and upper sidebands. + + 1 2 + 1 2 = 1 + 1 Assignment 1 Sol Page: 4 of 12 3. Let f(t) be a real signal. The transmitter transmits the following modulated signal = cos + sin Where is the Hilbert transform of f(t). (a) Explain that the modulated signal is a lower sideband SSB signal using an example of = cos . Solution: Note that there was an error in the question. The frequency of f(t) should be ? m inst ead of ? c. Any students with a reasonable attempt to this question will be awarded full marks. However, the solution below refers to the corrected problem. cos = sin cos + sin sin = cos = cos ? Since, cos ? = cos cos + sin sin ? = + ? + ? + For ? > 0, the impulse function is located to the left of the carrier frequency. For ? < 0, the impulse function is located to the right of –? c. Therefore, the modulating function produces lower sideband signals. (b) Determine the frequency of the modulated signal. Solution: From the expression of , the frequency of the modulated signal is ? . Assignment 1 Sol Page: 5 of 12 4. An SSB signal is generated by modulating an fc = 1 MHz carrier by the message signal = 2 cos 2000? t + cos 4000? t . The amplitude of the carrier signal is Ac = 1. a) Determine the Hilbert transform of f(t). Solution: = 2 cos 2000? t + cos 4000? t ? ? = 2 cos 2000? t ? + cos 4000? t ? 2 2 = 2 sin 2000? t + sin 4000? t (b) Determine the time domain expression of the lower SSB and upper SSB signals. Solution: ?  ± t = cos ? sin ? 2 sin 2k? t + sin 4k? t sin = 2 cos 2k? t + cos 4k? t cos = 2 cos 2k? t + cos 4k? t cos ? 2 sin 2k? t + sin 4k? t sin = 2 cos 2k? t cos + cos 4k? t cos ? sin 4k? t sin ? 2 sin 2k? t sin = 2 cos 2k? t cos ? sin 2k? t sin + cos 4k? t cos ? sin 4k? t sin  ± 2000 + cos  ± 4000 = 2 cos (c) Sketch the magnitude spectrum of the lower SSB. Solution: ? t = 2 cos ? 2000 + cos ? 000 ? ? = 2 + ? 2000 + 2 ? + 2000 + + ? 4000 + ? + 4000 A 2? ? -? c -? c+4000? -? c+2000? ?c-4000? ?c-2000? ?c ? (d) The coherent detection of the lower SSB signal consists of multiplying the received modulated signal by cos followed by a low pass filter. If the local (receiver) oscillator generates a phase error ? (i. e. the message signal is now multiplied by cos + , write the expression at the output of the low-pass filter and discuss how the phase error will affect the demodulated signal. Solution: Assignment 1 Sol Page: 6 of 12 Input of the L PF: = = = cos cos cos + + cos cos A cos B = sin A cos B = = os + sin + + cos sin + cos + cos A + B + cos A ? B sin A + B + sin A ? B cos 2 + + sin ? + sin 2 + sin ? A = ? sin A = cos + cos 2 + ? sin + sin 2 + Output of the LPF: = = cos ? sin 2 cos 2000? t + cos 4000? t cos ? 1 2 sin 2000? t + sin 4000? t sin 2 = cos 2000? t cos + cos 4000? t cos 1 ? sin 2000? t sin ? sin 4000? t sin 2 1 cos 4000? t cos ? sin 4000? t sin 2 = cos 2000? t cos ? sin 2000? t sin + cos A cos B ? sin A sin B = cos A + B = cos 2000? t + ? + cos 4000? t + ? Assignment 1 Sol Page: 7 of 12 5. A given DSB-LC transmitter develops an unmodulated power output of 1 KW across a 50-ohm resistive load.When a sinusoidal test tone with a peak amplitude of 5. 0 V is applied to the input of the modulator, it is found that the spectral line for each sideband in the magnitude spectrum for the output is 40% of the carrier line. Determine the following quantities in the output signal: (a) The modulation index. Solution: = + c os cos cos + cos cos = 1 1 = cos + cos ? + cos + 2 2 When a sinusoidal test tone with a peak amplitude of 5. 0 V is applied to the input of the modulator, it is found that the spectral line for each sideband in the magnitude spectrum for the output is 40% of the carrier line. 1 : = 0. 40 2 = : = 0. 0 (b) The peak amplitude of the lower sideband. Solution: A given DSB-LC transmitter develops an unmodulated power output of 1 KW across a 50-ohm resistive load. = /v2 = 1000 Am is the amplitude (or â€Å"peak†) of the modulated signal. We need to use the rms value when calculating DC power. = 1000 2 = 10 = 316. 27 Peak amplitude of the sideband = = 158. 11 (c) The ratio of total sideband power to carrier power. Solution: Total power of the sidebands = = Carrier Power = Ratio = : = . cos : = cos . + = . 0. 8 ? . = = 0. 32 + cos + (d) The total power of output. Solution: Assignment 1 Sol Page: 8 of 12 Total Power = + = 33kW e) The total average power in the output if the peak amplit ude of the modulation sinusoid is reduced to 4. 0 V. Solution: Changing the modulation sinusoid peak amplitude will affect the modulation index. 4 = 5 4 = ? 0. 8 = 0. 64 5 Ratio of total sideband power to carrier power = . : = . 0. 64 = 0. 2048 Total Power = + = 30. 12kW Assignment 1 Sol Page: 9 of 12 6. Suppose that a message signal f(x) has bandwidth B Hz. If f(x) is modulated by one of the modulation schemes DSB-SC or SSB or VSB, then for demodulation, the receiver must generate a (local) carrier in phase and frequency synchronous with the incoming carrier. This is referred to as synchronous or coherent demodulation. ) (a) Draw a block diagram for the demodulator. Solution: (b) Assume that there is a frequency error in the local carrier (the phase is correctly estimated). Give the expression of the Fourier transform of the output of the demodulator for the case of DSB-SC modulation, sketch the spectrum of the output signal, and compare it with the spectrum of the original signal ( you may assume an arbitrary shape of F (w)). Solution: = cos ? cos +? = = = = = 1 2 ? = 2 ? ? ? ? ? cos cos ? cos ? os ? +? cos +? +? cos 2 +? + cos 2 + ? + ? 2 ? +? Without frequency error: Assignment 1 Sol Page: 10 of 12 With frequency error: (c) Repeat (b) for the case of SSB-SC modulation (you may do so by choosing either upper SSB or lower SSB). Solution: + sin = cos Input to the LPF: ? = cos = = = = ? ? ? ? +? + cos cos + ? cos cos cos cos ? 1 2 ? ? sin +? +? cos + + cos 2 ? +? sin sin +? +? cos cos +? +? + = 1 2 sin ? cos ? + +? + 1 2 ? ? sin 2 sin ? ? 2 ? = ? ? 2 ? ? ? 2 + + ? 2 ? +? Assignment 1 Sol Page: 11 of 12 With frequency error: d) Suppose that you are an engineer who responds to design a modulation system for a coarse environment in which it is difficult to generate a local carrier in frequency synchronous with the incoming carrier during some period of transmission. Which modulation system would you like to recommend, DSB-SC or SSB? Justify your answer. Solutio n: For DSB-SC, we notice a distortion in frequency. For SSB, we only observe a frequency shift. Therefore, it would be better to use SSB for a coarse environment. Assignment 1 Sol Page: 12 of 12

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