<?php
$params1 = new stdClass(); 
$params1->p1 = true; 
$title1 = new stdClass(); 
$title1 = "ttl1"; 
$params2 = new stdClass(); 
$params2->p1 = false; 
$params2->p2 = true; 
$title2 = new stdClass(); 
$title2->title = "ttl2"; 
$params2->smallArr = array(); 
$params2->smallArr[0] = "sml"; 
$noname1 = new stdClass(); 
$noname1->params = $params1; 
$noname1->title = $title1; 
$noname2 = new stdClass(); 
$noname2->params = $params2; 
$noname2->title = $title2; 
$bigArr= array(); 
$bigArr[0] = $noname1; 
$bigArr[1] = $noname2; 
$obj = new stdClass(); 
$obj->bigArr = $bigArr; 
$obj->id = "id"; 
$json = json_encode($obj); 
var_dump($json);
$obj = json_decode($json); 
var_dump($obj);

string(138) "{"bigArr":[{"params":{"p1":true},"title":"ttl1"},{"params":{"p1":false,"p2":true,"smallArr":["sml"]},"title":{"title":"ttl2"}}],"id":"id"}"
object(stdClass)#7 (2) {
  ["bigArr"]=>
  array(2) {
    [0]=>
    object(stdClass)#8 (2) {
      ["params"]=>
      object(stdClass)#9 (1) {
        ["p1"]=>
        bool(true)
      }
      ["title"]=>
      string(4) "ttl1"
    }
    [1]=>
    object(stdClass)#10 (2) {
      ["params"]=>
      object(stdClass)#11 (3) {
        ["p1"]=>
        bool(false)
        ["p2"]=>
        bool(true)
        ["smallArr"]=>
        array(1) {
          [0]=>
          string(3) "sml"
        }
      }
      ["title"]=>
      object(stdClass)#12 (1) {
        ["title"]=>
        string(4) "ttl2"
      }
    }
  }
  ["id"]=>
  string(2) "id"
}