user: The Richard III Society said the 7ft (2.1m) long limestone monument would blend modern and medieval style decorations to reflect the king's life.
The group was closely involved in the project to find the lost king's remains, which was confirmed last week.
Leicester Cathedral, where Richard is expected to be reinterred in 2014, said it would consider ideas but no decision had yet been made.
Source: BBC History
Conflict, rebellion and murder - discover more about Richard III's life
Richard III died at the battle of Bosworth in 1485 while fighting a rebellion by the future Henry VII.
He was buried in the church of the Greyfriars in Leicester but the precise location was lost when the building was demolished.
Working with Philippa Langley, of the Richard III Society, a University of Leicester team uncovered a skeleton in September 2012 and its identity was confirmed earlier this month.
Despite a number of rival claims, Leicester Cathedral is preparing to take possession of the remains by summer 2014 at the latest.
A spokesman for the Richard III Society said: "The tomb design was commissioned by Philippa Langley in September 2010 at the very beginning of the Looking For Richard project.
"It is based on Richard's life, and what was important and meaningful to him, and the design was undertaken by a team of specialists with over 40 years of research into Richard III.
"The society is looking forward to working with the cathedral and Leicester City Council to honour the return of the king."
The society said it expected to meet the estimated Â£30,000 cost through donations.
Liz Hudson, from Leicester Cathedral, said officials would brief architects about its requirements for the tomb on 12 March, with final proposals expected in the summer.
She said: "There is an agreed process to make this decision and it will ensure all views are heard and considered. No proposals will be considered outside of this process.
"This process will give us a design that will be appropriate for a working, public, worshipping cathedral and for all those who come in future generations to visit King Richard's final resting place."
A temporary exhibition in Leicester about the project has seen more than 3,000 visitors since it opened on Friday with many people queuing for up to an hour.

Sum: A design for Richard III's tomb has been unveiled by an enthusiasts' group.


Article: Aziz Dweik, speaker of the Palestinian Legislative Council (PLC), was arrested at an army checkpoint, his chief of staff told AFP news agency.
The arrest happened in Jaba between Ramallah and Jerusalem as Dr Dweik was travelling by car to Hebron, Bhaa Youssef said.
Israel has confirmed the arrest.
Israeli border troops said he was detained for "involvement in terrorist activities".
Witnesses told the Palestinian Maan news agency that Israeli soldiers handcuffed and blindfolded Dr Dweik before taking him to an unknown destination.
Dr Dweik is a member of the Islamist Hamas movement, which governs the Palestinian territory of Gaza. However, he is based in the West Bank.
The Palestinian parliament has not met since Hamas seized control of Gaza in 2007 from the rival Palestinian Fatah Party.
Since then Fatah - backed by the West - governs the West Bank.
The BBC's Wyre Davies in Jerusalem says Aziz Dweik has remained an influential figure in Palestinian political circles.
Many will see his arrest as a provocative act and further proof than Israel is pursuing a policy of restricting the movements of senior Palestinian figures, he adds.
The arrest comes amid rising tensions between Israel and Gaza. On Wednesday Israeli aircraft attacked targets in Gaza and troops struck targets near the border fence between Gaza and Israel.
Last May, Dr Dweik was held at an Israeli military checkpoint in the West Bank along with three other Hamas MPs.
One of the group, Nizar Ramadan, was detained but the others were allowed to proceed.
Analysts say about 20 of Hamas's 74 MPs in the 132-member PLC are currently being held by Israel.
The majority, who include two former ministers, have been arrested in the West Bank since October 2010.
Last month Israel freed 550 Palestinian prisoners in the second and final phase of a deal that saw the release of Israeli soldier Gilad Shalit in October.
Sgt Shalit, 25, was seized in 2006 by Hamas militants who tunnelled into Israel.
Hamas is listed as a terrorist organisation by Israel, the US and EU, due to its refusal to renounce violence and recognise Israel. Under the group's charter, Hamas is committed to the destruction of Israel.
++++++++++
Summarize:

assistant: A senior Palestinian politician and member of the militant group Hamas has been arrested by the Israeli army in the West Bank.