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Time-division multiple access

Time-division multiple access is a channel access method for shared-medium networks. It allows several users to share the same frequency channel by dividing the signal into different time slots; the users transmit in one after the other, each using its own time slot. This allows multiple stations to share the same transmission medium while using only a part of its channel capacity. TDMA is used in the digital 2G cellular systems such as Global System for Mobile Communications, IS-136, Personal Digital Cellular and iDEN, in the Digital Enhanced Cordless Telecommunications standard for portable phones. TDMA was first used in satellite communication systems by Western Union in its Westar 3 communications satellite in 1979, it is now used extensively in satellite communications, combat-net radio systems, passive optical network networks for upstream traffic from premises to the operator. For usage of Dynamic TDMA packet mode communication, see below. TDMA is a type of time-division multiplexing, with the special point that instead of having one transmitter connected to one receiver, there are multiple transmitters.

In the case of the uplink from a mobile phone to a base station this becomes difficult because the mobile phone can move around and vary the timing advance required to make its transmission match the gap in transmission from its peers. Shares single carrier frequency with multiple users Non-continuous transmission makes handoff simpler Slots can be assigned on demand in dynamic TDMA Less stringent power control than CDMA due to reduced intra cell interference Higher synchronization overhead than CDMA Advanced equalization may be necessary for high data rates if the channel is "frequency selective" and creates Intersymbol interference Cell breathing is more complicated than in CDMA Frequency/slot allocation complexity Pulsating power envelope: interference with other devices Most 2G cellular systems, with the notable exception of IS-95, are based on TDMA. GSM, D-AMPS, PDC, iDEN, PHS are examples of TDMA cellular systems. GSM combines TDMA with Frequency Hopping and wideband transmission to minimize common types of interference.

In the GSM system, the synchronization of the mobile phones is achieved by sending timing advance commands from the base station which instructs the mobile phone to transmit earlier and by how much. This compensates for the propagation delay resulting from the light speed velocity of radio waves; the mobile phone is not allowed to transmit for its entire time slot, but there is a guard interval at the end of each time slot. As the transmission moves into the guard period, the mobile network adjusts the timing advance to synchronize the transmission. Initial synchronization of a phone requires more care. Before a mobile transmits there is no way to know the offset required. For this reason, an entire time slot has to be dedicated to mobiles attempting to contact the network; the mobile attempts to broadcast at the beginning of the time slot. If the mobile is located next to the base station, there will be no time delay and this will succeed. If, the mobile phone is at just less than 35 km from the base station, the time delay will mean the mobile's broadcast arrives at the end of the time slot.

In that case, the mobile will be instructed to broadcast its messages starting nearly a whole time slot earlier than would be expected otherwise. If the mobile is beyond the 35 km cell range in GSM the RACH will arrive in a neighbouring time slot and be ignored, it is this feature, rather than limitations of power, that limits the range of a GSM cell to 35 km when no special extension techniques are used. By changing the synchronization between the uplink and downlink at the base station, this limitation can be overcome. Although most major 3G systems are based upon CDMA, time-division duplexing, packet scheduling and packet oriented multiple access schemes are available in 3G form, combined with CDMA to take advantage of the benefits of both technologies. While the most popular form of the UMTS 3G system uses CDMA and frequency division duplexing instead of TDMA, TDMA is combined with CDMA and time-division duplexing in two standard UMTS UTRA; the ITU-T G.hn standard, which provides high-speed local area networking over existing home wiring is based on a TDMA scheme.

In G.hn, a "master" device allocates "Contention-Free Transmission Opportunities" to other "slave" devices in the network. Only one device can use a CFTXOP at a time. FlexRay protocol, a wired network used for safety-critical communication in modern cars, uses the TDMA method for data transmission control. In radio systems, TDMA is used alongside frequency-division multiple access and frequency division duplex; this is the case in both IS-136 for example. Exceptions to this include the DECT and Personal Handy-phone System micro-cellular systems, UMTS-TDD UMTS variant, China's TD-SCDMA, which use time-division duplexing, where different time slots are allocated for the base station and handsets on the same frequency. A major advantage of TDMA is that the radio part of the mobile only needs to listen and broadcast for its own time slot. For the rest of the time, the mobile can carry out measurements on the network, detecting surrounding transmitters on different frequencies; this allows safe inter frequency handovers, something, difficult in CDMA systems, not supported at all in IS

Chizh (album)

Chizh is the first album by Russian band Chizh & Co released in 1993. It is named after the nickname of the band frontman Sergey "Chizh" Chigrakov. Sometimes this album is referred as Sergey Chigrakov solo album, but it is included in official band discography. "Avtobus" - – 3:48 "V Starinnom Gorode O." - – 3:39 "Vechnaya Molodost'" - – 2:56 "Myshka" - – 2:19 "Russkaya" - – 3:28 "Glazami i Dushoy" - – 3:58 "Hoochie Coochie Man" - – 3:42 "Ona Ne Vyshla Zamuzh..." - – 6:46 "Takie Dela" - – 5:54 "Glupen'kaya Peshya" - – 4:30 Sergey Chigrakov: vocals, electric guitar, acoustic guitar Nikolay Korzinin: drum kit Sergey Berezovoy: bass guitar Mikhail Chernov: saxophone, flute Aleksandr Kondrashkin: percussion Ivan Voropayev: violin Aleksandr Brovko: harmonica Boris Grebenshchikov: vocals Mikhail Klimeshov: vocals Album description on band official site

Wiggins in Storyland

Wiggins in Storyland is an educational computer game designed for MS-DOS and Microsoft Windows. It was released by Virgin Sound and Design in 1994; the game centers around a green bookworm named Wiggins and features voice acting by Doug Preis, Joseph Siravo, Eden Rigal, Richmond Hoxie, Polly Adams, Daniel Rysnyder. Wiggins in Storyland features little actual gameplay. Players can write stories and poems using a wide assortment of animated backgrounds, animated characters and background music; the game was designed to allow children to write stories without being boggled by more complicated tools such as Microsoft Word. The game included over 40 characters, 110 props, eight different story themes, multiple type fonts, 40 different sound effects and background music. In short, the player is presented with a book taking up the entire screen, wherein the leftmost page could be written on whilst the rightmost was left empty. A toolbar at the top of the screen allowed the player to drag props and such onto the rightmost page to help illustrate the story.

The player may manipulate the animated characters in various ways—such as changing their size, facial expression, mood. Other than that, the player can record their story and hear it played back aloud. In addition to the story-writing section, the player may enter "Wiggins' Library", a point-and-click activity room. Activities within the library include painting the room, playing musical instruments, shooting peas with a spoon, making fruit juices for Wiggins to drink. Aside from all this, the window or rug can be clicked on to either play Tic-Tac-Toe or "The A-Maze-ing Rug"—a game in which the player attempts to catch the "bad guy" before the clock reaches zero

Lavelanet

Lavelanet is a commune in the Ariège department in the Occitanie region in southwestern France. The town is known for its former textile factories, its inhabitants are called Lavelanetiens. In 2002 the 13th stage of the Tour de France started in Lavelanet. In 2008 the 12th stage of the Tour de France started in Lavelanet; the name of Lavelanet comes from the Latin avellana meaning "hazel nut". The city is called Neout by the locals. Fabien Barthez, footballer Benoît Baby, rugby player Jean-Paul Banos and Jean-Marie Banos, fencers Perrine Laffont, mogul skier Daniel Lassalle, baroque trombonist Communes of the Ariège department INSEE

Moonlighting (film)

Moonlighting is a 1982 British drama film written and directed by Jerzy Skolimowski. It is set in the early 1980s at the time of the Solidarity protests in Poland, it stars Jeremy Irons as a Polish builder leading a team working illegally in London. Arriving in London from Warsaw in December 1981 are master electrician Nowak, who understands the language but not the inhabitants, with three workmen who know no English, their task is to gut and renovate a house, for which they have brought what tools they can carry, while Nowak has cash to buy materials. Since the whole operation is illegal, Nowak keeps them working indoors while he goes out to get food and supplies; as his money runs out, he takes to stealing. In the meantime, Poland is undergoing the traumas of demonstrations and strikes followed by the declaration of martial law, banning of Solidarity and mass arrests. All this Nowak conceals from the men. With no money left, they have a six-hour walk to the airport and a flight home to an uncertain future.

Jeremy Irons as Nowak Eugene Lipinski as Banaszak Jirí Stanislav as Wolski Eugeniusz Haczkiewicz as Kudaj Edward Arthur as Immigration Officer Denis Holmes as Neighbor Renu Setna as Junk Shop Owner David Calder as Supermarket Manager Judy Gridley as Supermarket Supervisor Claire Toeman as Supermarket Cashier Catherine Harding as Lady Shoplifter Jill Johnson as Haughty Supermarket Customer David Squire as Supermarket Assistant Michael Sarne as Builders' Merchant Jenny Seagrove as Anna Lucy Hornak as Wrangler Shop Assistant It was entered into the 1982 Cannes Film Festival, where it won the award for Best Screenplay. Roger Ebert gave it four stars out of four and included it in his list of Best Movies of 1982. Gene Siskel called it his favorite movie of 1982. Allmovie gave Moonlighting four out of five stars. Vincent Canby, in The New York Times, called Moonlighting "immensely rewarding", he added: "It may be a coincidence - maybe not - that two of the best films made about exile have been made by Polish directors", the other being Polanski's The Tenant.

Moonlighting on IMDb Moonlighting at AllMovie Moonlighting at Rotten Tomatoes Moonlighting at Box Office Mojo

Dublje (Svilajnac)

Dublje is a village in Serbia. It is located in the Pomoravlje District. According to 2002 census, its population numbers 1,050 people. There is a book about Dublje. Dublje is located 3 kilometers in the Central Serbia region; the village is situated on a high plain beneath the hill Hum. Dublje is well known in the region for having its own unique language, still spoken in some households today; the Dubljanski language is a mixture of Serbian language with plenty of Turkish words. Dublje is about two hundred years old, the settlers came running away from the Turkish people who decapitated many of the former who lived as villagers in Veliki Izvor near today's Zaječar and a few kilometers away from Bulgarian border. So, with their village burned to the ground for the fourth time, the survived villagers became frightened and decided to flee to the west and deeper into the woods and founded a settlement on a high plain near the river Resava and today's Svilajnac; the settlers i.e. the people who came from Veliki Izvor preserved their language, family names and personal names in spite of the new environment and people who surrounded them.

The families which kept the same names kept same slava and zavetina remained same in both villages. This instinct for self-preservation went so far that they preserved something better than their ancestors in the primary village. Apart from the language they preserved various rites and other customs and cultural'products'. Today, some customs, such as'Lazarice', still last whereas the same custom in Veliki Izvor disappeared 50 years ago. In Dublje the repeated Lazarice are normal for the young girls, who are dressed in their nicest dresses for that occasion, on Lazarus Saturday when they carry a basket and go from house to house collecting eggs and sweets for the approaching Easter. National clothing includes other various garments which only the Dubljani and the Velikoizvorci wear, like:'zabratka','takanici','na prestilki','na vlnenik','fusta', eleče', etc; these clothing are included when performing line dancing by which the Dubljani are famous and have several dances on their own. There are many folk songs which testify how people lived back in the past.

As for the Velikoizvorci, there is one folk song recorded about. Namely, this song tells us how a host, who had no lamb to sacrifice, decided to sacrifice his own first-born son. There are various customs and ceremonies performed on weddings and christenings. In the village, elderly people speak Dubljanski while the young speak Serbian, though they know and understand Dubljanski. Today, it is unthinkable for some parents to teach their children Dubljanski for they are ashamed of it, hence they do not speak Dubljanski at all or at least not in front of their children; the times changed and the language and many customs started dying out, so the Dubljanski will become a legend. In the center the village there are few shops, a cafe Boss,a school, a new church, under construction; the village is a quiet place during the day, when kids are at school and parents are busy farming or at work. But when evening comes the center comes to life when the young and elderly come out in the center to relax and socialize.

The younger inhabitants of the village spend their time watching football games or playing pool table at the local cafe, while the older generations play dominoes or chess. List of places in Serbia dublje.com