A helical antenna has a helix supported by a helix support. The helix support includes at least one piece of flexible sheet having its two surfaces covered with a layer antistatic material. The flexible sheet is curlable into a revolution surface configuration to form a revolution surface-shaped support section for at least partially supporting a portion of the helix component there around. A grounding mechanism electrically grounds the external sheet surface to the helix and the two sheet surfaces to one another when in the revolution surface configuration while a locking mechanism locks the flexible sheet in the revolution surface configuration. The combination of the helix and the flexible support renders the antenna structurally relatively rigid in all directions.