SOFTWARE DESIGNED RADIO

TIDES OF SOFTWARE DESIGNED RADIO

SOFTWARE DESIGNED RADIO

Software designed radio is a radio communication system where components that have been traditionally implemented in hardware are instead implemented by means of software on a personal computer. While the concept of SDR , the rapidly evolving capabilities of digital electronics render practical many processes which were once only theoretically possible.
A basic SDR system may consist of a personal computer equipped with a sound card, or other analog to digital convertors, preceded by some form of RF front end. Significant amounts of signal Processing are handed over to the general-purpose processor, rather than being done in special-purpose hardware.


APPLICATIONS OF SOFTWARE DESIGNED RADIO
The SDR concept is applicable in various areas

•MOBILE COMMUNICATION
                    Software defined radios are very useful in areas such as mobile communications. By upgrading the software it is possible to apply changes to any standards and even add new waveforms purely by upgrading the software and without the need for changes to the hardware. This can even be done remotely, thereby providing considerable savings in cost.

•RESEARCH AND DEVELOPMENT
       The radios can be configured to provide the exact receiver and transmitter requirements for any application without the need for a total hardware design from scratch.

•MILITARY
          The military have made much use of software defined radio technology enabling them to re-use hardware and update signal waveforms as needed.

•OTHERS
          There are very many other applications that can make use of SDR technology, enabling the radio to be exactly tailored to the requirements using software adjustments.

ADVANTAGES OF SDR
• It can perform at high rate.
• Performance can be changed by upgrading the software.
• It is possible to reconfigure radios by updating the software.
• The same hardware can be used for several different radios.

DISADVANTAGES OF SDR
• Analogue to digital converters limit top frequencies that can be used by the digital section.
• For very simple radios the basic platform may be too expensive.
• Development of a software defined radio requires both hardware and software skills.

PERKS OF HAM LICENSE

PERKS OF HAM LICENSE

HAM LICENSES

Any individual above the age of 12 can become HAM after qualifying Amateurs station operators examination and they can access a valid Amateur wireless telegraph station license. There are three types of license for HAM radio operators: Technician, General, and Amateur Extra. The license is valid for 10 years and you can renew it without taking an examination.

TECHNICIAN LICENSES

         All HAM starts with Technical license and it is also called as Tech license. These license holders are allowed to access for all HAM band with frequencies 50 MHz and above.  These privileges include operation at the maximum legal power limit and using all types of communications. They can transmit using voice on part of the 10 meter band and Morse code on some of the HF bands below 30 MHz. Technician class exam includes 35 multiple choice questions on technical radio topics.

GENERAL CLASS LICENSES

          After piece of pie  the entry-level Technician license, many HAM starts getting upgraded to General class licenses. General class licensees have full privileges on nearly all amateur frequencies, with only small portions of some HF bands remaining off limits.General class exam consists of 35 questions in which the topics are similar to Technician class but in more detail, and you are also introduced to some new topics.

AMATEUR  EXTRA CLASS LICENSES

            General class licensees still can’t access everything; the lowest segments of several HF bands are for Amateur Extra class licensees only. These segments are where the expert Morse code operators hang out and are considered to be prime operating territory. The Amateur Extra Class consists of 50 multiple choice questions out which 37 questions must be answered correctly to pass the examination.  The exam covers rules and regulations associated with sophisticated operating and several advanced technical topics.

WHAT CAN ONE DO WITH THE LICENSE

•          You can talk to other HAM.
•          You can build radio and antenna.
•          You can participate in fox hunt event.
•          you can transmit and receive pictures.
•          you can experiment with satellite communication.

According to the survey on April 2013 nearly 48.7% are  Technician license holders. Nearly 23.1%  are General Class license holders and about 18.5% are Amateur Extra Class license holders.

Role of amateur radio in Disaster Management

Role of amateur radio in Disaster Management: the unsung heroes

Disasters, both natural or man-made, do happen. A lot more often than needed. But we as humans have evolved pretty well to cope and improvise according to these situations. But our evolution may also be a curse in disguise.

As we have grown more and more tech savvy, we also became more and more dependent on tech. So much to a point where it's literally life or death. We use it for information, navigation, communication and much more. The problem arises when we suddenly lose access to this tech.

Let's take a calamity for instance. Such as the flood that occurred in Chennai. The rains were heavy and unstoppable. Hard and unbelievable. Annoying and unfathomable. The rich and the poor were united. There are only two types of people at a time like that. You either survive... Or you die.

At times like these the basic human requirements become a luxury. We no longer take it for granted. This includes water, food, shelter and technology. As discussed before, technology is vastly prevalent in communication. So that means no more calling with a phone, TV, Internet and radio... Except, we can still use radio with a few minor adjustments.

Amateur radio is similar to traditional radio broadcasting. Except they don't use for commercial purposes. They may use for other reasons such as entertainment, recreation, education, self practice, radiosport, and finally and most importantly, communication.

We use radio waves to send and receive audio over vast distances. This audio can be Morse code or even full fledged analog sentences. But during disasters, we don't really need to have giant antennas, since these calamities usually only happen within a few districts. So we can easily use small, compact and inexpensive gear to send and receive radio messages.

At a time when disaster strikes, and communication is down. We will need to get in contact with the people in charge in various parts of the affected city. If we need to rescue stranded citizens, we can't call the search and rescue on our phone. If there is a fire, we cannot call the fire department. If there is an injury, we cannot call an ambulance. If there is a problem, we cannot just call the police. It is in these situations where we need operators who contact these different departments during an emergency.

Therefore, the government sends a call for all the amateur radio operators in the vicinity and brief on the current situation. They are then stationed on different parts of the affected city. When there is an emergency, the people can tell these operators. These operators will then contact the police or other disaster relief departments and let them know what the problem is and where to come.

Hence, these amateur radio operators are a vital link between the affected people and the authorities. They risk their lives voluntarily to go to these dangerous places from the comfort of their homes to connect the people to their required help. They are unsung heroes. 

ANTENNA

As the developed of electronics increased in recent years, scientists and engineers have found a way to eliminate the use of traditional antennas such as Yagi antenna,Rabbit ear antenna etc.But the antennas aren't going anywhere,they are replaced by new technologies.Although antennas are generally considered to be outdated, telecommunication  companies are finding ways to innovate the antenna for next generation of electronics. As antennas are smaller, lighter,and more powerful than ever before they are used in wide areas such as 3D printers and manufacturing technique.
                                              
An antenna is a transducer that changes over radio frequency (RF) fields into alternating current or the other way around. There are both receiving and transmission antennas for sending or accepting radio transmissions. Antennas assume a significant job in the activity of all radio hardware. They are utilized in remote networks, portable communication and satellite correspondence.



                                  

They are arranged with metallic conductors where the electrical connection are given to the receivers and transmitters. Current is passed through these conductors and an alternating magnetic field is created.They induce voltage to the antenna.The magnetic field is coupled with similar oscillating electric field.It allows electromagnetic waves for propagation.

WHY DO WE NEED ANTENNAS?

There are several reason for using these antennas but the important reason is to provide a simple way to transfer signals when other methods are impossible.Working of any wireless device requires transmitting and receiving signals(or data) this is only possible with the use of antennas.There are many situation in which cables are preferred over wireless communication with antennas(like high speed Ethernet or the connection between gaming console and the T.V., for example).  

Stay tuned to learn about the types of antennas which will be posted next week.

Radio Frequency

RADIO FREQUENCY

Radio frequency is the activity representing the oscillation rate of  electromagnetic radiation spectrum, electromagnetic radio waves, from frequencies starting from 300GHz to as low as 9kHz. Radio frequency is measured in units called hertz, which represent the number of cycles per second when a radio wave is transmitted. One hertz equals one cycle per second. The unit Hertz is named in honor of the 19th-century German physicist Heinrich Rudolf Hertz.  With the utilization of antennas and transmitters, an RF field can be used for various types of wireless broadcasting and communications.

                                  

When it involves choosing  the right radio, the difficult task is to choose the right bandwidth to be utilized. the 2 major wavelengths used for communications are VHF (Very High Frequency) and ultrahigh frequency (Ultra High Frequency).

VHF

VHF’s frequency range is from 30 MHz to 300 MHz. VHF has 10 times longer wavelength. This means the waves are longer with VHF therefore it travels further. The VHF radio band specifically for commercial radios is between 130 -174 MHz. If you're operating largely outdoors, a VHF radio maybe the most effective selection, particularly if you are employing a base station radio inside and you add the external antenna. The higher you can place the antenna, the further you can transmit and receive.VHF radios also have a smaller number of available frequencies.One benefit of VHF wireless radios is that battery life is almost always better than for similar UHF units. For handheld radios this is a plus.The VHF band is used for two-way radio communication. a good deal of satellite communication and broadcasting is done at VHF.

                               
                                    

VHF waves, not like longer waves, are not strongly reflected from the atmosphere; therefore, they don't bend  round the Earth’s curvature and cannot  be transmitted beyond the horizon. VHF waves are  restricted to use in short-range, line-of-sight communications, together with radio and television broadcasting, and in electronic navigation systems.

UHF

Ultra high frequency (UHF) refers to the band of  electromagnetic radiation with a frequency varying  between 300 MHz and 3GHz. This band is also called as the decimetre band, with a wavelength starting from 1 m to 1 dm. UHF is used for data transmission with shorter wavelength and high frequency. Since the size of antenna is directly proportional to the size of the waves, the antennas for UHF are short and stout. Higher the frequency band lower the size of antenna.The broadcast range is shorter than VHF.

                     

                                  

UHF is used in two-way navigation, wireless local area network and communications, radio and security systems.

For example,  When you’re in an area with lots of small obstacles, such as a circle track or stadium race where there’s lots of people, you’re going to need a signal that can travel in between gaps of those obstacles to the receiver you’re talking with. This is where UHF signal will provide a greater range because of the smaller waves. VHF is suitable for wide range, but in this case UHF is used for better transmission quality.

A HAM is an amateur radio, it is a wireless communication technology. It brings people, electronics and communication together. Radio amateurs have access to frequency allocations throughout the RF spectrum. This enables communication across a town, region, country, continent, the world, all without the Internet or cell phones. It's fun, social, educational, and can be a lifeline during times of need. Amateur radio operators are known as technical innovators, and have been responsible for important discoveries. In several countries, amateur radio operators may additionally send, receive, or relay radio communications between computers or transceivers connected to secure virtual private networks on the web. A HAM Radio station can be set up anywhere, at club station or even at home. To operate on radio frequencies one should pass the examination conducted by the FCC(Federal Communications Commission). Amateur Communication is done on various bands from 1.8 MHz to several hundred gigahertz.

HAM Club of KCT

The HAM Club of KCT was inaugurated on 4th October 2018. The logo of the club was launched on the same day. Since then several events were conducted. Workshops entitled Radio For Everybody was held on 4th Feb 2019 and during Yugam 2019 Events such as HAM Horror Hunt, Fox Hunt and Walk with Walkie were conducted during 7th,8th and 9th February.

                                                 

The Club Incharge Mr.Karthikeyan led the HAM relief operation for Gaja Cyclone at Karaikal. The real heroes faced a lot of hurdles but the need to help kept them going. 

HAM LENS

HAM Lens is an event with innovative questions to tackle your interest and curiosity about disaster and rescue measures. It was a good platform for the participants to bring out their communication skills, Puzzle solving skills and Social awareness. At first the participants were divided into teams, the host of the event explained them the usage on working of HAM. The team of two students were asked to pick a virtual situation randomly and they were made to communicate through HAM.
                                   

The event was entertaining and informative. It gave a clear idea to act during critical situations and made the participants realize their level of communication and logical thinking.