RF Venue CP Beam Antenna at the Tokyo Olympics

As part of the drastic measures taken to curb the spread of the virus, events took place entirely behind closed doors in the Japanese capital which was declared a state of emergency over the pandemic.

The Games saw 339 events take place in 33 sports, including new sports such as surfing, karate, rock climbing, skateboarding and baseball/softball.

Coordinating and monitoring radio frequencies for wireless microphones and in ear monitors for an event of this size requires many months of careful preparation. RF Engineer Steve Caldwell, based at the NW Group in Sydney Australia, has managed RF at every Olympics since 2000 (with the exception of Beijing). Steve relies extensively on the RF Venue CP Beam helical antenna in his RF system designs.

The lightweight CP Beam helical antenna is easy to transport and folds down to be packed away in a 3RU rack drawer

So what does it take to flawlessly pull off such a huge event?  Setup commenced 4 months prior to the opening ceremonies.  For the program’s wireless mics, Steve and his team deployed 72 channels of Shure Axient AD4Q receivers arranged into 24 channels of Quadversity at the mains position at FOH, and 24 channels in a backup location under the performance stage in diversity mode. 

On the IEM side, Steve used 16 channels of PSM1000 for the high level performers along with 64 body packs.  8 channels of Sennheiser SR2050s were used for the level 2 group performers along with 160 EK300 body packs.  The mass cast (numbering in the thousands) carried FM broadcast packs.  Any guesses how many batteries that might take and how many power “on” switches had to be checked?

The RF Venue CP Beams were used as the primary receiving antennas for the radio microphones at all 4 Ceremonies, as well as the rehearsal periods: A pair of CP Beams at the FOH position on the western side of the stadium and another pair, connected by an RF over Fibre link, on the north-east side of the stadium.

The two pairs of CP Beams fed the inputs of the Axient Digital receivers, which were used in Quadversity mode. A third pair of RF Venue CP Beam antennas was used on a separate receiver position under the performance stage.

“Two brands of antenna and models were installed at FOH, however the CP Beams were chosen after significant testing, due to their excellent front to back ratio and ideal beamwidth pattern,” says Steve Caldwell.

After careful planning and coordination, everything worked flawlessly with no drop out.

“All radio microphones used across the bandwidth exhibited excellent coverage due to the helical antennas, with very low interference as a result of the RF Venue CP Beams excellent front to back ratio,” says Steve. “This effectively eliminated most RF noise sources from the stadium concourse behind. All antennas were exposed to full weather conditions for 4 months during the time of the Olympics set up, with no issues of any kind.”